19 94ApJS. . .94. .749K the answertooneofastronomy’sstillunsolvedpuzzles—that trinsic faintness.Yet,itisthisfaintnesswhichmightprovide dwarfs arethemostcommon,butfewcomprehensivestudies tial toadeeperunderstandingofGalacticstructure.Ofstars, M THE LUMINOSITYFUNCTIONATENDOFMAINSEQUENCE:RESULTSADEEP,LARGE-AREA, presence ofasuspected,thoughstillunconfirmed,population of substellarobjects—theso-calledbrowndwarfs. fainter insearchoftheseobjectsshouldultimatelyreveal the of theGalacticmissingmass.Inaddition,probingfainter and of themhavebeencompleted,primarilybecausetheir in- Telescope Observatory,afacilityoperated jointlybytheSmithsonianIn- Texas, Austin,TX78712-1083. stitution andtheUniversityofArizona. © 1994.TheAmericanAstronomicalSociety.Allrightsreserved.PrintedinU.S.A. The AstrophysicalJournalSupplementSeries,94:749-788,1994October 2 1 A betterknowledgeofourownsolarneighborhoodisessen- Presentaddress:McDonaldObservatory, RLM15.308,Universityof Observationsreportedherewere obtainedwiththeMultipleMirror 2 2 derivation ofthemass-luminosityrelation(fromHenry&McCarthy)areusedtocomputeamassfunction because theoldercounterpartsofthispopulationhavecooledbeyondcurrentdetectionlimits.Thelatterscenario the limitingvolumeof19.4degnorthernsample,instarkcontrasttosmaller7.9areaatsoutherly would holdiftheselate-typeMdwarfsaresubstellar.Theluminosityfunctiondatatogetherwithanempirical either becausethelowermetallicitiesprevalentatearlierepochsinhibitedformationoflateMdwarfsor latitudes wheresevensuchdwarfsarefound.Thisfact,combinedwiththefactthatSunislocated—10-40pc luminosity functioncover27.3degdowntoacompletenesslimitofR=19.0.Thisfunction, Subject headings:stars:low-mass,browndwarfs—luminosityfunction,massfunction smaller thanthe350pcvaluegenerallyadoptedforotherMdwarfs.Theseobjectscompriseayoungpopulation north ofthemidplane,suggeststhatlatestdwarfsarepartayoungpopulationwithscaleheightmuch upturn atfaintmagnitudesexistsonlyinthesouthernsample.Infact,nodwarfswithMj>12.0arefoundwithin When theluminosityfunctionissegregatedintonorthGalacticandsouthportions,itfoundthat spectral typeslaterthanM6—aneffectsuggestedinearlierworkbyReid&GilmoreandLeggettHawkins. computed aF,7,andbolometricmagnitudes,showsanincreaseatthelowestluminosities,correspondingto has beenobservedspectroscopicallyatthe4.5mMultipleMirrorTelescopetoassesscontributionsbygiantsand sampling Galacticlatitudesof+90°downto—35°.Aselection133objectschosenviaR-7andF—7colors CCD/Transit Instrument,adedicatedtelescopesurveyingan825widestripofskycenteredat5=+28°,thus M6 orlaterhavebeendiscovered,withthelatestbeingoftypeM8.5.Datausedfordetermination subdwarfs andtoverifythatthereddesttargetsareobjectsofextremelylatespectralclass.Eighteendwarfstype the massofGalaxy. mass functionsareindicativeofalarge,unseen,substellarpopulation,browndwarfsmayyetaddsignificantlyto density ofMdwarfsisstillinsufficienttoaccountforthemissingmass.Ifincreasesseeninluminosityand independent oftheory.Thismassfunctionincreasestowardtheendmainsequence,butobserved The luminosityfunctionattheendofmainsequenceisdeterminedfromF,R,and/datatakenby © American Astronomical Society • Provided by theNASA Astrophysics Data System 1. INTRODUCTION Institute forAstrophysics,UniversityofNewMexico,Albuquerque,NM87131 Steward Observatory,UniversityofArizona,Tucson,AZ85721 Steward Observatory,UniversityofArizona,Tucson,AZ85721 James LiebertandDonaldW.McCarthy,Jr. Received 1993November29;accepted1994March24 CCD SURVEYFORCOOLDWARFS' John T.McGrawandThomasR.Hess 2 J. DavyKirkpatrick ABSTRACT AND 749 _3 -3 lactic pole(SGP),concluded thatthereisnomissingmassin Gilmore (1989a),usingdata onKdwarfsnearthesouthGa- reality ofthis“missingmass.” Bienaymé,Robin,&Crézé served valueof0.10-0.11A7© pc(Bahcall1984).Kuijken& mass densityof0.09-0.12AT© pc,consistentwiththeob- ( 1987)usedatechniquebased onstarcountstoobtainalocal pc awayandwouldhaveapropermotionexceeding1" per form ofunobservedmatter.Heshowedthatiftheseunseen half ofthemassinsolarneighborhoodmustreside the missing mass.UsingtechniquespioneeredbyOort(1932, annum. objects havemassesbelow0.1A/©,thenearestonewould be 1 stars isanimportantstepinunravelingthemysteryof the 1960), Bahcall(1987,andreferencestherein)determined that Knowledge oftheluminosityfunctionforleastluminous Recent results,however,havebeguntocastdoubtuponthe 1.1. TheMissingMass 19 94ApJS. . .94. .749K 6 jects basedonthelithiumdoublet at6708A.Destructionof greater thanthis. However,theinteriortemperature forbrown also beenaddressedbyother groups.Rebolo,Martin,&Ma- and latermaybesubstellar. interiors ofeventhelowest massstarshavetemperatures lithium occursattemperatures greaterthan~2X10K;the gazzù (1992)proposedaspectroscopic testforsubstellarob- and spectroscopicinformationofthesecondariesinfive low- & McCarthy(1994,hereafterPaperIV)togamerphotometric object. ThespectralsequencewasfurtherusedinKirkpatrick and possessesaspectrumunlikethatofanypreviouslyknown candidate isindeedcoolerthananyMdwarfyetdiscovered mass binarysystems,suggestingthatMdwarfstypedas M7 trum ofGD165BinKirkpatrick,Henry,&Liebert(1993a, hereafter PaperIII),establishingthefactthatthisbrowndwarf ture scaleinKirkpatricketal.(1993b,hereafterPaperII). The spectral sequencewasthenusedasacomparisontothespec- set oftheoreticalspectratodeterminetheMdwarftempera- addressed inKirkpatrick,Henry,&McCarthy(1991,hereafter Paper I).Thesespectrawereextendedto1.5/anandfitteda late-type starshasalreadybeenacquired;specifically,thesig- is alreadyinplace.Spectroscopyofacomprehensiveset nature ofK5toM9dwarfsbetween6300and9000Âwas distinguished byaparametermoreeasilymeasuredthanthe geneity intheBienayméetal.(1987)starcountsample,aswell mass. this mayintroduceunwantedsystematicerrors. be treated,accordingtoBahcalletal.(1992),withcaution,as One ofthegoalsistoseeifstarsandbrowndwarfscanbe searchers willbeabletocomparethetwogroupsofobjects. imply asubstantialfractionofmissingmatter.Theinhomo- vital todeterminingtheobservableparametersoflowest mass stars.Oncetheirsubstellarcounterpartsarefound,re- as inthecombinedKdwarfsampleofKuijken(1991),should concluded thatamorerobustanalysisofthesamedatawould the Kuijken&Gilmore(1989a,b)massdeterminationsand ate solarvicinity. absolute magnitudemaystilllieunrecognizedintheimmedi- white dwarfshasbeendemonstratedtobenegligible(Liebert, the contributiontolocalspacedensitybylow-luminosity Dahn, &Monet1988),Mdwarfsandbrownoffaint nosity degenerates,faintMdwarfs,orbrowndwarfs.Although well understood.Ina“one-experiment”run,theyfoundthat estimate inwhichthesystematicandrandomuncertaintiesare is missingmass,themostlikelypossibilitiesareverylowlumi- model havingnodarkmatterisinconsistentwiththedataatan used dataonKgiantsattheSGPtoproducealocalmass ing anearbysampleofKdwarfsinadditiontotheSGP Gilmore 1989b).Kuijken(1991)confirmedtheseresultsus- 86% confidencelevel.Theseauthorsgaveacriticalanalysisof sample. the solarvicinity,withsameresultbeingfoundwhena reanalysis ofdataonFdwarfsandKgiantsisused(Kuijken& 750 This spectroscopicdelineationofstarsandbrowndwarfshas Some ofthespectroscopicgroundworkforthisinvestigation Studies ofobjectsattheendmainsequencearealso Clearly, thelasthasnotbeenwrittenonthissubject.Ifthere In responsetotheseclaims,Bahcall,Flynn,&Gould(1992) 1.2. VeryLowMassStarsandBrownDwarfs © American Astronomical Society • Provided by theNASA Astrophysics Data System KIRKPATRICK ETAL. tion arepresentedin§6.Theresultssummarized § 7. nosity functionisgivenin§5.Implicationsforthemassfunc- § 4.Comparisontopreviouslypublishedversionsofthelumi- The derivationoftheCTIluminosityfiinctionisdetailed in be usedtoverifythatobjectsfallingintheintrinsicallyfaintest and mostcrucialbinsarelegitimateobjectsofextremetype. tion byobjectssuchasMgiantsandsubdwarfscan also can provideadequatestatisticsonthepercentageofcontamina- pling ofstarsfoundinthehigherluminositybins).These data targets foundinthelowestluminositybins(aswellasasam- nosity functionhasobtainedspectratocheckthemajorityof photometric determinationofthefaintendstellarlumi- luminosity functionforMdwarfsisproduced.Nootherrecent gether withphotometryofallstarsintheCTIdatabases,a cussed in§3. tude limitofthesurvey,andtoidentifypreviouslyunknown, ducted bytheCCD/Transit Instrument, otherwiseknownas spectroscopic targetsandthefollow-upobservationsaredis- accuracy oftheCTIphotometry,particularlynearmagni- luminosity functionistheresult ofanongoingsurveycon- very lateMdwarfsinthesolarneighborhood.Theselectionof also beentargetedspectroscopicallyinanattempttoassessthe § 2.SomeoftheobjectsdiscoveredinCTIdatabaseshave dwarfs andofanypossiblysubstellarobjects.TheCCD/Tran- utilizes two320 X512RCACCDsalignedwith columnsinthe sit Instrument(CTI)usedtoconductthissearchisdescribedin large areaofskytodeterminethespacedensitycoolest the CTI.TheCTIisaL8m,f/2.2 meridian-pointingtelescope located onKittPeak,Arizona. Ithasnomovingparts,but be fullyunderstoodandplacedincontextwithcurrentbrown covered andcanbestudied. dwarf theoryonlywhenotherextremelycoolobjectsaredis- example, thedifferencesbetweenMdwarfsandGD165Bwill objects withtypesofM8orlaterareknown(PaperIII).Asan of theselate-typeobjectscanbeidentified;lessthanadozen cooler dwarfsexhibitstrong,unidentifiedabsorptionfeatures objects. spectroscopic peculiaritieswerealsonotedamongthesefour possibly duetounrecognizedpolyatomicmolecules.Other from 1.5to2.4pm.Themostnotabledifferenceisthatthese from thespectraofanM7andM8dwarfoverregion spectra ofanM8.5andM9dwarfweremarkedlydifferent in theinfrared.Davidge&Boeshaar(1993)foundthat are moremassivethan0.06M. (1993) failedtodetectthedoublet,suggestingthatthesedwarfs dwarfs lessmassivethanabout0.06Mneverreachesthis six low-luminosityMdwarfsbyMagazzù,Martín,&Rebolo should occurinobjectsofthistype.Aspectroscopicstudy critical value.Asaresult,nosignificantdepletionoflithium 0 Q Using thiscomplementaryspectroscopicinformationto- The photometricdatabaseused inthedeterminationof In thispaper,aphotometricsearchisundertakenover Further researchcannotbecarriedoutuntilalargersample Spectroscopic studiesofthelatestMdwarfshavealsobegun 2. THECCD/TRANSITINSTRUMENT(CTI) 1.3. OutlineofthePaper Vol. 94 19 94ApJS. . .94. .749K 2 hms hms the strip,withAlbireo(ßCygni)fallingjustoutside. Cygnus andagaininGemini/Taurus),probesasfarsouth6« through theNorthGalacticPole,crossesplaneofGalaxytwice(in stellations areshownalongitscourse.Notethatthestripcrossesnearly —35°. NotealsothatPollux(¡3Geminorum)andScheat(ßPegasi)fallin grate” (TDI)modeattheapparentsiderealratetoforman east-west directionandoperatedina“time-delayinte- No. 2,1994 image ofthetransittingsky(McGraw,Cawson,&Keane full rangeofrightascension.Thetelescopeispointedatadecli- that thestrippassesnearlythroughNorthGalacticPole the courseofCTIstripthroughGalacticcoordinates.Note contained withintheTaurusMolecularCloud.Figure1shows central portionoftheComaBerenicesgalaxyclusterandareas nation of+28°,whereitcanmonitor,forexample,boththe (NGP), crossestheplaneofgalaxytwice,andprobesasfar south oftheplaneas£^-35°.Figure2ashowsatypicalfield the LTT(LunarTransitTelescope),isnowbeingdesignedfor shows afieldneartheGalacticplane.Inyear’stimeCTI near theNGP.ThiscanbecomparedtoFigure2b,which 1986). Thestripis825wide(northtosouth)andspansthe deployment ontheMoon’ssurface(McGraw1992). surveys about45deg.Asecondgenerationofthisinstrument, with the/filterandiscenteredat R. A.(1950)195430.Notetheplethoraofobjects.Bothframes are4'onasidewithnorthupandeasttotheleft. at R.A.(1950)125100.Notethe paucityofobjects,(b)(right)Atypical1minuteCTIexposureinthe GalacticplaneinCygnus.Thisframewasalsotaken Fig. 1.—PathoftheCTIsurveyinGalacticcoordinates.Familiarcon- Fig. 2.—(a)(left)\typical1minute CTIexposureinComaBerenicesneartheNorthGalacticPole.This framewastakenwiththe/filterandiscentered © American Astronomical Society •Provided bythe NASAAstrophysics Data System LUMINOSITY FUNCTIONATENDOFMAINSEQUENCE technique whichaveragesallspatialinstrumentalcorrections ute, anobjectwilltraverse512linesontheCCD,sampling into morestablelinearfunctions.Inthespaceofabout1min- results inaflatterflatfield.Biasacquisitionisdonesimilarly. only aflat-fieldlineneedstobemeasured,andthisaveraging flat fieldverticallyasittransitsthedetector.Insuchasystem, through aVfilterwhiletheotherobservesB,R,orI that theCTIwillremaininfocusregardlessoffilterchoice, depending upontheskybrightness.Becauseitisnecessaryto tometric standards;calibrationtoanexternalsystemisdis- Cousins BVRIsystem,witheachfilterhavingathicknessof3 CTI filtersystemisslightlydifferentfromtheJohnson/ maintain auniformopticalpathlengththroughthefiltersso a morecomprehensiveoverviewoftheCTI,readerisre- cussed in§4.1.ThenightlylimitingmagnitudeisF^21.For mm. CTIphotometryisbootstrappedtoaninternalsetofpho- and photometricparametersarecalculatedforeach.Thesepa- ferred toMcGrawetal.(1986). contains informationoneverydetection,sortedbyrightascen- contain thebestestimateforeachparameter.The“poollist” rameters becomepartofa“poollist”and“masterwhich bandpass thereisalsoa“historylist”whichmaintainslight been repeatedlydetectedonnightsofgoodseeing.Foreach sion. The“masterlist”isasubsetofthe“poolcontaining the CTIdatareductionprocesscanbefoundinCawson, example, veryfaintentriesareconsideredrealiftheyhave only thoseobjectshavingahighlikelihoodofbeingreal;for curve foreverydetectedobject.(Astep-by-stepdescriptionof McGraw, &Keane1986a.) photometry. Eachentryinthe“pool”and“master”listsgives, parameters determinedusingallavailable,reducednightsof among otherparameters,therightascensionanddeclination (for the1987.5equinox)ofobject,averagemagnitude Photometric precisionisenhancedbyutilizationoftheTDI One ofthetwoCCDsinfocalplanealwaysobserves The pixeldataaresearchedtofindeverydetectableobject, The datalistedforeachobjectarevariance-weightedmean 751 19 94ApJS. . .94. .749K h h h hm hm were performedon~2ofthe 24totalinthestrip.Unfortu- the “poolfist.”Co-additionsin Ren,/cn,andsometimesF^ to probedeeperthanthenightly limitingmagnitudesgivenin sive process,whichiswhyonly atotalof~2hasbeencom- nately, thisisanextremelytime-consuming andlabor-inten- cause ofthereddeningpresentoverthisarea. Molecular Cloudcomplex,wasexcludedfromthesearch be- ing 4000''2yr . giving theequinox1987.5coordinates(epoch—1990).Col- signal-to-noise ratiosof—7or better.Forthe17objectshaving ratios areshowninFigure3 foreachofthespectrahaving Paper I(andrepeatedinthetitlesofFig.3).Thevaluesthese spectra weredeterminedusingcolorratiosalsodefined in integration. Column(9)listsnotesonselectedobjects,includ- umn (6)givesthespectraltypesdeterminedfromMMT tion oftheobject—acode,denotedbyhhmmss.s+ddmmss, MMT observationalongwiththelengthofspectroscopic spectra, andcolumns(7)(8)givetheUTdateof the object inequinox1950coordinates(againwithepoch umn (2)givestherightascensionanddeclinationof each right ascensioninTable1.Column(1)givestheCTIdesigna- to 9000Â.Intotal,133spectrawereobtained,wherespecial very redtargets.Theseobjectsarelistedinorderofincreasing emphasis wasplacedonacquiringspectraofthemajority the databaseshavebeenmeasurements,soonlylight tional comparisons.CTIlightcurvescanalsobeproducedto setup describedinPaperI,whichprovidescoveragefrom6300 nel ofthe4.5mMultipleMirrorTelescope(MMT)using curves atcancurrentlybeexamined.) check forpossiblevariability.(Mostofthedataenteredinto can becomparedtoPOSSprintsofthesamefieldcheck the single-nightdata. the “poollist,”veryfewextremelyredstarswerefoundthat gions wereexcludedfromthesearchdiscussedin§3.1.1(too Rcri improvestheRenlimitby—1.8mag.However,manyof visually forpropermotion.Thisvisualcheckisreliableonly 0015, Ol^012770251138 which extendsthelimitbyonly1magorless. the areashaveonly2or3nightsof/cndataand4Ren> field hasasufficientnumberofstellarimagestouseasposi- for propermotionsexceeding—0''2yr,andthenonlyifthe had notpreviouslybeendiscoveredduringinterrogationsof near theplane)andthatregionsprobemoredeeplythan 2254, and2336.Despitethefactsthatsomeofthesere- adding 9nightsat/cnenablesthesurveydatatoprobe—2.2 those atF^hadasmany27.Ithasbeenfoundthatco- general, thecoadditionsat/cnincludednomorethan9nights mag deeperthanasinglenight’sdata,andco-adding8nightsat that areashavingthemostarchiveddatacouldbeselected.In — 1990).Columns(3)-5giveinternalCTIphotometry. Col- of (high-quality)data,thoseatRenhadnomorethan8,and pleted. Smallregionsspanningonly~5inR.A.wereusedso 1803, I90019122027212206 1342, 1415150639ló^ m Spectral typeswereassignedusingtheleast-squaresminimi- The color-selectedtargetswereobservedwiththeRedChan- Once theredobjectshavebeenselected,theirfindercharts The R.A.centersforeachofthe5co-addedregionsare 3.1.3. OtherDataontheTargetObjects 3.2. SpectraofCTIObjects 19 94ApJS. . .94. .749K 001251.1+280535A 000455.2+280301 000139.94-275821 CTI Name 002142.1+280548 000928.8+280436 000537.5+275850 000351.34-280138 000055.2-f280432 021845.9+280047 015812.8+280439 012657.5+280202 012517.7+280101 012023.2+280321B 012023.2+280321A 011708.6+275850 005100.5+280430 004911.4+275952 004525.7+280437 004406.7+280336 004244.4+280140 003439.1+280309 002352.0+280605 001251.1+280535B 011826.7+280514 010332.0+280234 002603.4+275922 093631.3+280237 092539.9+280018 092423.0+280044 084106.0+280016 075013.2+280613 023210.0+280313 015825.4+280120 015705.9+280519 015625.5+280135 015607.7+280241 015338.5+280036 015115.8+280458 014716.6+280142 013743.0+280553: 012517.7+280247 012303.4+280449 092053.7+280101 091716.8+280531 090928.9+280324 090120.6+280439 081722.3+280138 075723.2+280533 072401.2+280238 065950.5+280228 035750.4+280105 131541.3+280227 124832.6+280502 124450.0+280024 120236.8+275947 120144.1+280527 115638.4+280000 113104.4+280200 112443.6+280426 111035.6+275951 065150.8+280311 064951.4+280442 034607.5+280109 034036.8+280248 032659.6+275912 032442.5+280400 112750.0+280406 105802.4+280251 105707.5+280223 105201.6+280448 103000.3+280432 102840.1+280330 031502.6+280315 100219.5+280036 © American Astronomical Society • 00:42:06. 00:21:54. 00:19:44. 00:10:54. 00:10:54. 00:03:41. 00:02:59. 00:01:55. 23:59:44. 23:59:00. RA (1950)Dec 00:40:44. 00:32:39. 00:24:05. 00:07:32. 09:34:20 09:23:27 09:22:10 09:15:03 09:07:15 08:38:50 07:55:04 07:47:54 07:21:40 06:57:29 03:55:32 03:38:19 03:22:26 01:53:59, 01:24:52. 01:23:12. 01:18:18. 01:18:18. 01:16:22. 01:15:04. 01:01:29. 00:48:59. 00:47:10. 00:43:25. 03:43:50 03:24:43 03:12:47 02:29:58. 02:16:35. 01:56:17 01:56:04. 01:54:57. 01:54:17, 01:51:30. 01:49:08. 01:45:09 01:37:37, 01:23:12. 01:20:58, 13:13:54 12:46:42 09:18:41 08:59:06 08:15:04 06:49:29 06:47:29 12:42:59 12:00:41 11:59:48 11:29:05 11:54:42 11:25:50 11:22:44 11:08:34 10:55:59 10:55:04 10:49:58 10:27:54 10:26:34 10:00:11 .7 +27:49:33 .4 +27:50:30 .0 +27:54:28: .6 +28:14:19 .9 +28:17:18 .9+28:17:59 .4 +27:54:57 .7 +28:12:19 .6 +28:14:25 .1+28:16:48 .5 +28:12:05 .1 +28:11:57 .4 +28:05:38 .1 +27:54:11 .7 +27:55:35 .5 +27:56:06 .5 +27:50:23 .9+27:51:06 .9 +27:49:20 .8 +27:53:05 .9+27:51:34 .9+27:51:34 .6 +27:53:25 .7 +27:46:59 .6+27:50:30 .5 +27:52:16 ,6 +27:47:37 .3 +27:52:19 .4 +27:51:18 .3 +27:49:21 .9 +27:50:45 .2+27:46:55 .1 +27:53:37 ,4+27:53:19 .4 +27:53:04 .4 +27:53:04 .5 +27:52:05 .2+27:46:18 .5 +27:50:29 ,7 +27:49:06 .0 +27:52:00 .8 +28:16:30 .8 +28:14:26 .4 +28:16:46 .6 +28:16:05 .3 +28:15:02 .0+28:11:29 .2 +28:12:44 .8 +28:10:03 .8 +28:10:27 .2 +28:10:36 .9 +28:14:59 .4 +28:13:31 .2 +28:08:19 .9 +28:08:39 .9 +28:07:04 .4 +28:05:56 .9 +28:07:21 ,4 +28:12:35 .3 +27:54:40 5 +27:45:49 4 +27:53:19 4 +27:50:37 6 +27:50:27 6+27:51:42 2 +27:53:52 5 +27:53:43 8 +27:54:22 6 +28:12:32 8+28:14:54 5+28:11:38 5+27:51:24 1 +27:50:25 +28:12:42 Rcti (R-1)CTI(V-I)ctiSp.TypeDateObs.(UT)Int.(s)Note 19.61 19.00 17.47 18.39 14.17 18.47 18.51 18.50 14.91 14.49 14.78 14.22 18.50 18.97 18.98 18.99 16.97 19.96 15.67 15.95 15.96 17.00 15.87 18.33 17.30 15.32 19.30 15.83 17.90 16.98 15.83 15.43 15.37 14.91 18.27 14.04 17.57 15.35 16.92 18.57 18.27 18.95 14.29 14.69 19.30 11.12 14.46 17.69 18.33 15.05 18.5: 19.35 16.39 13.28 0.26+0.01 17.93 19.00 15.37 18.47 15.45 18.55 18.32 19.12 0.75 +0.01 0.51 +0.01 2.35 +0.17 2.17 +0.41 0.26 +0.01 0.88 +0.01 0.78 +0.01 0.84 +0.01 0.57 +0.01 0.17 +0.07 0.55 +0.01 0.50 +0.01 0.97 +0.22 0.75 +0.01 0.74 +0.12: 0.59 +0.01 1.82 +0.27 0.55 +0.02 0.20 +0.01 0.99 +0.01 2.30 +0.24 0.35 +0.04 1.42 +0.09 1.52+0.11 1.68 +0.07 1.78 +0.14 1.74 +0.26 1.83 +0.40 1.41 +0.08 1.25 +0.06 1.34 +0.02 1.12 +0.03 1.06+0.03 1.19 +0.02 1.86 +0.08 1.29 +0.07 1.21 +0.01 1.53 +0.03 1.77 +0.12 1.56 +0.11 1.04 +0.05 1.17 +0.02 1.47 +0.09 1.19 +0.04 1.94 +0.16 1.18 +0.02 1.42 +0.07 1.03 +0.02 1.99 +0.08 1.51 +0.09 1.60 +0.14 1.80 +0.24 1.59 +0.14 1.65 +0.07 1.18 +0.14 1.85 +0.21 1.00 +0.01 1.75 +0.01 1.83 +0.12 1.95 +0.21 CTI ObjectsObservedSpectroscopically 4.08 ±0.06 2.00 +0.01 2.85 +0.01 2.67 +0.01 2.01 +0.01 3.18 +0.05 3.17 +0.04 4.08 +0.01 4.99 +0.6: 3.88: 3.06 +0.09: 2.75 +0.03 2.56 +0.01 2.86 +0.01 3.29 +0.07 3.17 +0.04 2.84 +0.01 3.21 +0.05 2.01 +0.01 2.93 +0.01 3.50 +0.02 4.05 +0.54 2.19 +0.18 3.58 +0.12 2.45 +0.01 3.52 +0.14 2.28 +0.01 2.37 +0.01 3.89 +0.08 2.57 +0.01 3.76 +0.19 2.42 +0.16 3.56 +0.13 3.23 +0.05 2.28 +0.01 3.28 +0.07 3.24 +0.07 2.21 +0.01 2.58 +1.02 2.39 +0.18 3.51 +0.05 2.79 +0.14 3.01 +0.05 0.82 +0.19 2.98 +0.18 3.04 +0.19 3.29 +0.17 3.26 +0.06 3.19 +0.02 2.81 +0.02 2.89 +0.84 3.37 +0.08 3.61 +0.04 3.03 +0.09 3.18 +0.10 2.96 +0.16 3.03 +0.05 2.68 +0.03 1.40 +0.06 1.91 +0.01 1.59 +0.01 1.50 +0.01 1.75 +0.03 1.51 +0.01 1.94 +0.01 1.99 +0.01 Provided bythe NASA Astrophysics Data System TABLE 1 sdMO M4.5 V M4 V M5.5 V M2.5 V M6: V M4 V K7 V M5.5 V M6 V M3.5 V M4.5 V M4 V K7 V M4 V M3.5: V M3.5 V Ml.5 V Ml V M6 V M4.5 V M5.5 V M7 V M5.5 V M3: V M2.5 V M3 V M5 V M5.5 V M3 V M3 V M6.5 V M3 V Ml.5 V M6 V M3.5 V M5.5 V M5.5 V M5.5 V M4 V M4.5 V M4.5 V M5.5 V M5.5 V M5 V M4.5 V M4.5 V M4 V M3.5 V M6 V M3: V M4 V M6 V M3.5 V M4 V M4.5 V Ml.5 V M6 V M5.5 V < K5V M6 V M4.5 V M8.5 V MOV MOV M6 V M7 III Ml.5 V K7 V M4.5 V M6 V M6.5 V M3.5 V M3.5 V 1991 Jun22 1990 May04 1991 Mar14 1990 Jan21 1991 Mar14 1991 Mar14 1991 Mar14 1990 Jan20 1990 May04 1990 Jan20 1990 Jan20 1990 May04 1991 May07 1991 Mar14 1990 Jan21 1991 Mar14 1990 Jan20 1991 Mar14 1990 Jan21 1990 Jan20 1990 May04 1990 Nov22 1990 Jan20 1990 Jan21 1990 Jan20 1990 Nov22 1990 Nov22 1990 Nov22 1990 Sep13 1990 Nov22 1991 Jun24 1989 Jul14 1990 May04 1991 Mar14 1990 Nov22 1990 Jan21 1990 Jan21 1990 Jan21 1990 Jan21 1990 Jan20 1990 Nov22 1991 Oct17 1991 Oct17 1991 Oct17 1991 Oct17 1989 Jul13 1989 Jul14 1990 Nov23 1990 Jan22 1989 Jul13 1990 Nov23 1990 Sep13 1990 Nov23 1990 Jan22 1989 Jul13 1990 Nov23 1990 Nov23 1990 Nov22 1990 Sep13 1989 Jul13 1990 Nov23 1989 Jul13 1990 Nov23 1990 Nov23 1990 Nov23 1990 Nov23 1990 Sep13 1989 Jul14 1990 Nov23 1990 Nov22 1990 Sep13 1990 Nov23 1990 Jan22 1989 Jul10 900 360 4200 2700 2100 300 2700 2100 3000 2700 2100 3900 300 600 600 2700 390 900 300 3900 1200 1500 1170 1800 3900 2700 3660 2700 2700 600 600 3900 3900 2700 600 600 2700 600 3900 2700 3900 2700 2700 2700 2700 300 300 2100 2361 1200 1200 1200 1170 1500 3900 900 3900 3900 2700 2700 2700 2400 300 1500 1500 1200 1500 1500 1500 1200 1800 1200 1500 1500 1 1 -1 1 = -1 -1 ,,1 -1 H ~O^'yrtowardSE. fi ~O^'yrtowardW? // ~O^'yrtowardN??Icti=17.92 fi ~0.2"yrtowardSE? Close doublewithfollowingstar. Icti 16.90 Icti =17.89 Icti =18.06 Icti =17.38 Icti =17.44 H ~P'yrtowardWSW? Not foundonPOSS-E.(Large/i?Toofaint?) Close doublewithprecedingstar. Large fi?NotfoundonPOSS-Eprint. LP 322-1178(seeTable5). Not foundonPOSS-E.Icti=17.43 Icti =17-57 /i ~OA^yrtowardE?Notcolor-selected. Icti ~17.5 Close doublewithprecedingstar. Close doublewithfollowingstar. Not foundonPOSS-E.Icti=16.67 LP 301-16(seeTable5). /i ~2yr"towardWNW?? H ~l.S'^rtowardN?? Not foundonPOSS-E.(Largefi?Toofaint?) Variable. IctiandpossiblyRctisaturated. 19 94ApJS. . .94. .749K -1 1 proper motionsinexcessof ~0''2 yr.Theseareallmid-to lie closetothePOSS-Eplatelimit, leavingtheidentificationof late-M dwarfs.Severalofthese aresufficientlyfaintthatthey has shownthatanumberof objectslistedinTable1have /)cri and(R-fromK7 throughM8.5. objects, demonstratingthemonotonieincreaseofboth( V— Table 1.FigureAbshowsthespectraltypesofeachthese CTI 141111.3+280141,confirmingourby-eyeestimatesof/u~Qf'2 yr". 234957.0+280136 233828.2+275817 223752.5+275918 233201.1+275943 232425.5+275949 230047.6+280216 224056.1+280052 202928.1+280151 202738.5+280227 225508.6+280234 225431.2+280046 225024.0+275956 202636.9+275934 754 191326.8+275930 191258.9+280353 192853.3+280415 192121.7+280100 191216.9+280228 190917.7+280305 190016.9+280541 190006.8+280452 180408.2+280352 180516.3+280448 180456.3+280049 180350.6+280133 185818.3+275940 185818.3+280045 180305.0+280256 162920.5+280239 180257.2+280456 180216.8+280457 162356.1+275942 154231.3+280401 153948.1+280322 CTI Name 180142.2+275924 174729.0+280322 171818.0+280512 170958.5+275905 160557.4+280437 153945.1+280233 180120.1+280410 162342.9+280305 161340.2+280024 161340.2+280011 153915.6+280445 153915.5+280214 153729.8+280454 150546.8+280117 150225.7+280231 141329.8+280131 141237.7+280557 133827.9+280633 135752.6+275957 135347.7+280419^ 134402.7+280521 133857.8+280437 131631.6+280541 141111.3+280141^ 141034.2+280158 A comparisonoftheCTIfinder chartstothePOSS-Eprints f AlsodiscoveredaspropermotionobjectsbyLuyten(1979;seeTable 5),whoobtainedß=(X'lSOyr © American Astronomical Society • Provided by theNASA Astrophysics Data System 23:48:03 23:36:35., 23:30:09.' 23:22:34. 22:58:59, 22:53:20.; 22:39:09. 22:36:06.' 22:52:43 22:48:36. 20:27:54. 20:26:04. 20:25:03. 19:27:22. 19:19:51. 19:11:56. 19:11:29. 19:10:47. 19:07:47. 18:58:37. 18:56:48. 18:56:48. 18:03:47. 18:58:47. 18:03:27. 18:01:36. 18:01:28. 18:00:48. 18:02:39. 18:02:22. 17:08:29. 16:27:49. 18:00:13. 17:59:51 17:46:00. 17:16:49. 16:22:25. 16:22:12 16:12:08 16:12:08 16:04:25 15:40:58 15:38:14 15:38:11 15:35:56 15:37:42 15:37:42 15:04:10 15:00:49 14:11:49 14:10:57. RA (1950)Dec 14:09:30. 14:08:53. 13:56:10 13:52:05 13:42:19 13:37:13 13:36:43 13:14:45 .0 +27:49:05 .5 +27:45:49 .2 +27:47:17 .0 +28:08:14 .6 +28:10:38 .7 +28:10:36 .7 +28:09:47 .8 +28:05:50 .2 +28:12:00 .0 +28:09:29 .8 +28:09:57 .5 +28:11:19 ,8 +27:57:38 .8 +27:56:33 .7 +28:04:33 .7 +28:00:35 .6 +28:03:41 .0 +28:01:23 .4 +28:02:48 .7 +28:04:49 .3 +28:04:52 .6 +27:59:21 .5 +28:04:08 .4 +28:04:05 .0 +28:07:30 .2 +28:01:50 .9 +28:07:31 .2 +28:04:50 .3 +28:12:14 .2 +28:12:00 .0+28:16:28 .4 +28:12:14 .3 +28:12:32 .7 +28:16:01 .1+28:16:38 .7+28:17:58 .0 +28:17:32 .4 +28:10:53 .1 +28:15:21 2 +27:50:10 8 +27:50:33 5 +27:48:46 8 +27:48:00 9 +27:49:06 6 +27:47:35 4 +27:56:41 4 +27:47:27 0 +27:54:17 6 +27:54:58 0 +27:52:07 8 +27:59:33 8 +27:55:36 0 +28:00:00 4 +28:02:28 0 +27:58:37 9 +27:59:24 3 +28:01:39 1 +28:11:07 +28:06:03 20.02 20.17 9.99 18.62 15.18 16.62 19.85 18.22 19.50 19.45 15.64 15.32 14.08 11.56 19.79 19.61 13.07 12.71 14.80 11.20 19.53 20.24 20.15 14.50 18.75 15.75 18.79 15.93 18.92 19.01 15.38 18.50 18.52 19.78 15.46 16.55 14.70 17.02 19.09 19.51 18.31 15.46 19.87 18.74 15.38 15.45 Rcti (R-I)cti(VSp.TypeDateObs.(UT)Int.(s)Note 17.84 16.39 19.57 17.35 18.96 15.93 0.77 +0.27 2.21 +0.42 0.98 +0.28 0.98 +0.48 0.45 +0.03 0.48 +0.03 2.28 +0.06: 2.49 +0.73 0.69 +0.01 2.21 +0.57 0.09 +0.01 0.77 +0.01 1.87 +0.33 1.14 +0.03 0.80 +0.27 0.33 +0.01 0.82 ±0.40 0.73 +0.02 0.73 +0.22 0.79 +0.03 1.94 +0.38 1.82 +0.37 1.46 +0.01 0.85 +0.27 1.08 +0.01 0.62 +0.02 2.21 +0.41 0.94 +0.07 0.54 +0.01 2.14 +0.80 0.80 +0.03 0.85 +0.68 1.48 +0.01 1.56 +0.38 0.61 +0.01 0.83 +0.14 0.75 +0.01 1.57 +0.17 1.58 +0.03 1.29 +0.14 1.19 +0.05 1.77 +0.41 1.55 +0.28 1.57 +0.12 0.65 ±0.02 1.65 +0.91 1.58 +0.82 1.33 +0.03 1.43 +0.08 1.60 +0.06 1.81 +0.43 KIRKPATRICK ETAL. 2.28 +0.25 2.91 +0.25 2.09 +0.43 2.86 +0.02 3.56 +0.01: 3.75 +0.01 2.84 +0.01 2.93 +0.34 3.78 +0.01 2.20 +0.01 1.82 +0.03 1.89 +0.03 2.28 +0.01 0.67 +0.07 2.46 +0.21 2.45 +0.13 2.25 +0.01 2.30 +0.02 2.28 +0.01 1.36 +0.01 3.57 +0.10 3.65 +0.01 2.63 +0.02 2.98 +0.06 3.02 +0.45 2.17 +0.01 2.85 +0.02 2.42 +0.15 3.44 +0.04 2.09 +0.01 3.12 +0.01 3.47 +0.02 1.72 +0.01 1.99 +0.15 2.36 +0.01 3.51 +0.03 1.99 +0.01 3.23 +0.14 1.95 +0.31 2.14 +0.02 1.63 +0.29 TABLE 1—Continued sdMO: M5 V M2.5: V M6 V M5.5 V M4 V Ml V Ml V M5 V M4 V M3 V M4 V M4 V M4 III MO V M4.5 V M7 III K7 III M2.5 V M3 III M4.5 V M4 V M6 III M5.5 III M3 V MOV M3 V M2.5 V M2: V M3 V M6.5 V M4 V M5 V M5.5 V M4 V M3 V M2.5 V M4 V M4.5: V M5.5 V M3 V M5.5 V M2 V Ml.5 V M6.5 V M4: V M4.5 V M5.5 V M2.5 V M3 V declination. Thenorthernandsouthernextremitiesare the completenesslimitthroughoutsurveyregiontobe beyond Ren=19.5.Basedontheseplots,wedetermine where disthedistancetostarfromSun.Thescale 28°06'35". Theareaencompassedbythestripisgiven prediction demonstratesthattheCTIsurveyisnotcomplete ized totheobservedcountsbrighterthanR=18.5.The above valueofM=10.5forstarsinthesampleandnormal- line inFigures5aandbisthispredictionderivedusingthe counts fromonebintothenextcanbepredicted.Thedotted ß =300pcdoesnotchangetheresults. ß =350pcisadoptedhere,butitcanbeshownthatavalueof (1981a) andas300pcbyGilmore&Reid(1983).Avalueof height ofdwarfMstarsisgivenas350pcbyMihalas&Binney data examinedhere{b=±35°),thisexpressionbecomes will beusedsinceintheseregionsthedatahaveanegligible value ofE(R-/)<0.02. data forvariouscolorsalongdifferentlinesofsight,and his R.A. <300,7261812or>21 51 Orion regionisexcluded.Therefore,onlythedatahaving average measurementofE(R-I)/E(BV)is0.80if the reaches 0.06mag.Johnson(1965)presentsmeanextinction except fortheregion319.5,andfortwoofthem,theerrorson(R— colors whichareconsistentwiththerestofdata.Each a deviate fromthetrend.Thesesamethreestarshave{V-/) pected, exceptthatthreepointshave{R—I)cncolorswhich of increasingcolorwithlaterspectraltype,aswouldbeex- {V- /)andagainst{R—1)^•Onbothplotsthereisatrend also presented.Here,Mdwarfspectralclassisplottedagainst objects isgiveninTable2.Asadiagnosticcheck,Figure6 ( 1992).AlistingofKCandCTIphotometryforeachthese reduced accordingtotheproceduresoutlinedinMonetetal. Cousins system(hereafterdenotedbythesubscriptKC)and USNO 1.0mreflectoronUT1992June20andJuly1,2, CCD photometrywasobtainedinFlagstaff,Arizona,atthe spectral typeswaschosenforcalibrationphotometry.This 5, and6.TheobjectswereobservedatV/ontheKron- source ofcontaminationisessentiallyzero. use oftheCTIcolor-colordiagram(see§4.3.2)meansthatthis ies arefoundamongthe133spectroscopicidentifications,and sures thatcontaminationbygiantsisalsonegligible.Nogalax- ously small.Thus,excludingareasneartheGalacticplaneas- color inthedwarfcalibrationequationswouldbeconspicu- within —10°oftheGalacticplane,andseventhissuffi- ciently brightthatthedistancederivedusingits(R-I) also discoveredamongthe133spectroscopictargets.Sixfall KC revealed twosubdwarfsoutof133objects.This~2%contami- which arenotdwarfshasbeenexaminedin§3.2.Spectroscopy nation bysubdwarfsisnegligible.Atotalofsevengiantswas KC m Datapointhasbeenremovedfrom subsequentanalyses.Seetextforde- Using Table1,asubsetofstarshavingrangeMdwarf Contamination oftheCTIphotometricdatabyobjects a a a 4+280437 5+275918 9+280228 0+280322 0+280512 2+280011 3+280401 6+280445 5+280214 8+280131 3+280141 3+280227 0+280256 5+275905 7+280557 7+280419 1+280410 1+280322 1+280233 USNO PhotometryofCTImDwarfs 4.1.3. ContaminationbyNondwarfs M3 Ml M4 M2.5 M2.5 M6.5 M5 M5.5 M5.5 M3 M5.5 M2 Ml.5 M6.5 M4: M2.5 M5.5 M6 M4 4.2. PhotometricCalibration 17.897+.021 16.403+.023 17.872+.022 18.191+.037 16.705+.034 14.737+.016 14.044+.016 18.444+.026 14.579+.024 14.583+.018 15.764+.020 14.098+.019 14.763+.020 17.171+.027 14.876+.034 14.699+.025 16.830+.022 13.903+.024 17.306+.022 TABLE 2 4.433+.117 4.271+.197 2.124+.056 2.815+.058 2.355+.031 2.458+.042 3.543+.055 3.687+.054 2.976+.043 2.059+.056 2.265+.028 3.366+.123 3.674+.031 3.916+.062 2.501+.096 3.620+.062 2.213+.026 {V -I)kcIcti 2.946+.057 2.368+.042 17.96+.10 14.16+.01 17.73+.06 18.59+.11 14.63+.01 16.41+.02 15.75+.01 14.84+.03 17.40+.08 14.76+.01 17.57+.11 16.93+.06 13.88+.01 17.32+.06 16.74+.03 14.85+.01 14.65+.01 14.14+.01 15.02+.01 0.54+.01 0.80+.03 0.48+.03 0.62+.02 2.21+.41 0.61+.01 2.14+.80 0.75+.01 2.21+.57 0.73+.02 (R —I)cti 1.43+.08 1.57+.17 1.58+.03 1.77+.41 1.55+.28 1.57+.12 1.65+.91 1.60+.06 1.21+.01 757 19 94ApJS. . .94. .749K an the equation tween (R-I)ctid(V—/)kc.Thisisshowngraphicallyin Figure 7.Aweightedlinearleast-squaresfittothedatayields omitted fromFigure8. begins toturnbluerwithlater spectraltype,thetwoM9Vstars as M9andbecausethisisthe point atwhichthe(V—/)color LHS 2924and2065in Monetetal.(1992)havebeen omitted. Inaddition,because theCTIstriphasnostarsaslate can bemade.ThesedataarepresentedinFigure8,where the Monet etal.(1992),atransformationfrom(V-/)toM ing theerrorsforcoefficients.) /) hasbeenoffsetby1.50and(F—3.25inequation This fitisshownbythesolidlineinFigure7.(Forequations [6] —sothatitfallsnearthemiddleofdata,thusminimiz- [ 6]-9].theoriginofeachfithasbeenadjusted—e.g.,( R- dwarfs listedinTable2.Thethreediscrepantpointsonthe(R—1)^plot relation agreeswellwithFig.\aofLeggett(1992)andTable2 are labeledwithopencirclesonbothpanels.This(F-I)vs.spectralclass Bessell (1991). 18 subdwarfsand10whitedwarfsintheirFigurehavebeen KC KC Ikc CTIKC 758 These datacanbeusedtodeterminethetransformationbe- Using CCDphotometryandparallaxdatapresented in Fig. 6.—(V—f)and(JÏ-1)^vs.Mdwarfspectralclassforthose KC (R -Der,1.50=a+b[(VI)3.25],(6) KC © American Astronomical Society • Provided by theNASA Astrophysics Data System where a=-0.136±0.019 and è=0.713±0.022. Dwarf MSpectralClass KIRKPATRICK ETAL. line representsasecond-orderleast-squares fittothedata. tion canbeappliedthatdependsonlyuponthevalueofa/ir. to theseresultingpointsgivestherelation been omittedfromFigure8.)Asecond-orderleast-squaresfit terminate corrections,sopointswithlargeparallaxerrorshave the volumeofspacebetweenparallaxvaluesttand-ais cally toolarge.Lutz&Kelker(1973)haveshownthatacorrec- and hencetheresultingabsolutemagnitudeswillbesystemati- larger thanthatsampledbetweenparallaxvaluesofttand+ a starfartheraway(tt-0.175haveinde- each A/.Aparallaxvalueoftt±=-0.107±0.055. d =2.334±0.053, e2 + l(V—I)kc~3.25],(7) Yol. 94 19 94ApJS. . .94. .749K -1 -1 -1 _1 1 1 The solidlinerepresentsaweighted linearleast-squaresfittothedata. vious relation,whereasthebrightendofhigh-velocitysam- low-velocity sampleinFigure10#fallslargelyabovethepre- (solid line)fromFigure8isshown.Thebrightendofthe intermediate-velocity subsample(-100kms—30kms);Figure10èshowsthe into threedifferentVvelocitybins.Figure\0ashowsthelow- Gliese &Jahreiss(1991).AccordingtoMihalasBinney transformation willbeappliedrepresentaphotometricallyse- motions of-150kms.Figure10breaksthestarsin8 (1981b), theVspacemotionsofMdwarfsaveragearound lected sample.Toaddressthisbias,U,F,Wspacemotionsfor tion (7),thedatausedtoconstructthisrelationarebased been removedfromFigure8beforethedeterminationofequa- the luminosityfunction.Althoughobvioussubdwarfshave -100 kms“).Foreachpartofthefigure,second-orderfit many oftheobjectsplottedinFigure8havebeenfound and Giclas).Ontheotherhand,CTIdatatowhich (mainly objectschosenfromthepropermotionlistsofLuyten primarily uponakinematicallyselectedsampleofobjects —15 to—19kms",whereassubdwarfshaveaverageFspace is, however,ofutmostimportancetoanaccuratederivation into avalueofManddistanceforthatobject. transforms the/cnand(R-/)cnvaluesforanygivendwarf quires asmallcolorterm.Theabovesequenceofequations well. Thisfitisgivenby showing thatthetransformationbetweentwosystemsre- least-squares fit,shownbythesolidfine,representstrend (data fromTable2)ispresentedinFigure9.Aweightedlinear (V- /)k,afewtenthsofmagnitudeinM. misleading, asthespreadinmetallicitycontributes,atagiven However, theformalerrorsoncoefficientsaresomewhat color-magnitude relationgiveninTable5ofLeggett(1992). Equation (7)agreestowithin0.1-0.2magwiththeolddisk /kc C/kc No. 2,1994LUMINOSITYFUNCTION Fig. 9.—TheA/vs.(F—/)diagram forCTIobjectslistedinTable2. KC A correcttransformationofcolorintoabsolutemagnitude Finally, canberelatedto/.AplotofA/vs.(F-/) KC —= © American Astronomical Society • Provided by theNASA Astrophysics Data System fen Acc/+gt(V~-f)kc“3.25],(8) where /=0.020±0.009, and £=-0.072±0.010, AT ENDOFMAINSEQUENCE759 tion, thecoefficientsabovearelesswelldeterminedthanthose tions. Nonetheless,thesetwo equations areidenticalwithinthe for equation(7). Because therearefewerdatapointsonwhichtobasethis rela- errors givenforthecoefficients, soforsubsequentanalyses, choose starsregardlessofkinematics,thetruecalibration ity stars.Becauseaphotometricallyselectedsample will higher velocitystars;equation(9)isbiasedtowardlow-veloc- only thebetterdeterminedequation (7)willbeused. somewhere betweenthecalibrations givenbythesetwoequa- needed toconverttheCTIcolors intoabsolutemagnitudeslies fine) tothelow-velocitysubsample,givenby ature, metalpoorMdwarfshavebluer(F-/)colorsthan pie inFigure10cfallslargelybelow.Atagiveneffectivetemper- solar-metallicity Mdwarfs(see,e.g.,Fig.12ofMonetetal. M -11.50=h+y[(F-/)3.25] squares fittothelow-velocitydata,asgivenineq.(9). brighter magnitudes.In(æ)thedashedlineshowsasecond-orderleast- Note thatthelow-velocitysampletendstofallaboverelationat only, {b)intermediate-velocitystarsand(c)high-velocityonly. 1992), sotheeffectseenhereislargelyduetometallicity. /kcKC The calibrationgivenbyequation(7)isbiasedtoward Figure \0ashowsasecond-orderleast-squaresfit(dashed Fig. 10.—Fittedrelationfrom8shownfor(a)low-velocitystars 1.5 22.533.54«5 where h=-0.908±0.088, and k=-0.060±0.089. j =2.399±0.098, 2 + k[(V—7)kc~3.25],(9) 19 94ApJS. . .94. .749K m ms to Figure1,ßCygni[Albireo], doesnotfallintherangeof also affected.(Theotherbright starmentionedinthecaption the CTIsurveyareadefinedin§4.1.2.imagesshow the right ascensiondiscussedhere.) ThefainterstarsinTable3 long; asmallerarea(<3long) aroundßPegasi(Scheat)is affected regionaroundßGeminorum (Pollux)tobe~330 longer wavelengths.Theidentificationoftheseaffectedareas CTI photometryofneighboringobjectstobetoobright at type themselves.Presumablytheirscatteredlightintroduces would beexpectedfromarandomdistributionofMdwarfs (Hoffleit &Jaschek1982)findsnoadditionalobjectswithin stars isgiveninTable3.AcheckoftheBrightStarCatalogue resulted intheremovalof117objects.Alistthesebright uncertainties intothebackgroundsubtraction,causing the nearby, brightstarwasfound.Thesestarsaregenerallyof late a preponderanceofredobjects,andateachtheseregions a along thestrip.Inparticular,thereare12smallregionshaving dates. values ofrightascensionthatoccurmorefrequentlythan exceeding 100pc.Thisresultedinthediscoveryof283candi- tion forallidentifiedobjects;see§2).Thedataweresearched for allobjectshavingM>8.00andderiveddistancesnot (unlike the“poollist”whichincludesphotometricinforma- objects thathaveahighprobabilityofbeingrealdetections “master list”wasusedsincethisdatabasecontainsonlythose minimized. (Seediscussionin§4.1.2.) the starcountstonormalizecomputeddensityvalue other uncertaintyintothecalculations. curately known)scaleheightandwouldthusintroducean- given distancedependsupontheGalacticlatitudeandhence the luminosityfunction.First,however,adistancelimitof100 in thesolarneighborhood.Thisfactordependsupon(inac- ered andthefaintlimitingmagnitudeattainedbythissurvey parsecs willbeimposeduponthesample.Thelargeareacov- upon therightascension,wouldhavetobeincorporatedinto sity at100pcisevenlessthanthis.Ifobjectsmuchgreater more obliquelyalongtheGalacticplane,decreaseinden- value inthesolarneighborhood;forareasstripthatlook the surveyimposesadistancelimitof50-75pc).Thereason a sampleofobjectscannowbeselectedfordetermination and withthetransformationstoastandardsystemestablished, sity ofMdwarfswillhavedroppedto75%(seeeq.[3])its negligible atthisdistance.AttheNorthGalacticPole,den- for limitingthesamplevolumetothisradiusistwofold: for thebinsoflowestluminosity,wheremagnitudelimit in theluminosityfunctiondespitethisdistancelimit(except assure thattherewillbeasufficientnumberofobjectsperbin /kc 100 pcweretobeincluded,theexponentialfactor,whichfora 760 The selectionofcandidatesindicatesthattherearesome For thecalculationofluminosityfunction,CTI 2. Fordistancesunder100pc,reddeningproblemswillbe With completenessandcontaminationproblemsassessed 4.3.2. ScrutinyofthePhotometricallySelectedObjectsvia 1. Thedropinstardensityforareasoutoftheplanewillbe © American Astronomical Society • Provided by theNASA Astrophysics Data System 4.3. AnalysisofthePhotometricData 4.3.1. ImposedDistanceLimit Internal Checks KIRKPATRICK ETAL. ahbc Bright, ContaminatingStarsin(orNeartheEdgeof)CTIStrip this brightstar. proper motionvalueslistedintheSAOCatalog. 2 m 85220 91472 90981 90732 82706 80511 80181 79666 79434 75520 75137 SAO #RA(1987.5)DecmSpecTotalNote jects, Figure\2aisproduced. Thisplotshows(R-1)^versus v At firstglance,Figure\2aappears toshowasecondsequence (R -/)forthoseobjectsin Table4havingphotometry. of starslyingbeneaththesequence definedbythemajorityof with anotherobjectontheCCDframe. they fallofftheplotasshown.)Usingthisplot,19additional tion ofanothereightobjects.Anotherobject,CTI chosen tobei^n=20.0.)Thiscriterionhasledtheelimina- M6 V. observed spectroscopicallyandhavetypesrangingfromM3 to Table 4.FifteenoftheobjectswithM<12.0havebeen determination oftheluminosityfunction.Thesearelisted in and thosepointswithdiscrepantphotometryaredenoted by data. Aplotof(F-1)^vs.(R/jcnfortheseobjects is has beentakentobe=19.0,thelimitingmagnitudeis objects areeliminated,leavingatotalof136for the open circles.(Threeadditionalpointsaresodiscrepant that sequence stars(definedbyFig.4)aredenotedfilledcircles, results ofFigure4canbeemployedtodiscardobviously bad of theluminosityfunction.(Althoughcompletenesslimit objects withR>20.0havebeenusedinthedetermination large photometricuncertaintiesforextremelyfaintobjects,no shown inFigure11.Objectslyingalongthelocusofmain- have /,R,andVmeasurements,socolorcriteriabasedonthe spurious andarenotconsideredfurther.Also,becauseofthe 002737.2+280025 andCTI170411.6+280620,areconsidered yet neitherwasdetectedatV.Thesetwoobjects,CTI CTI ofRen and(R-/jenwouldindicatethat19.0foreach, d c it wouldincreasetheresultinglogarithmicspacedensitiesby b a only 0.003. right ascensionisassumedtobeunuseablebecauseofbright instead of27.3.Thissmallchangeintotalareaisnegligible,as stars, thentheuseableportionofstripisonly27.1deg, contaminate muchsmallerregions.Ifatotalareaof~7in 103415.5+280117, hasbeenexcludedbecauseitismerged /kc CTI RmagnitudeandspectraltypefromTable1(CTI021845.9+280047). Numberofobjectsoutthe283totalwhosephotometryisaffectedby ValuestakenfromtheSAOCatalog,unlessotherwisestated. Processedtoequinox1987.5andupdatedepochusingthe CTl To aidinfurthercheckingthe validityofthesebrighterob- For theremaining155objects,thosewithA/<12.0all Two additionalobjectswereexcludedbecausetheirvalues 7kc 23:45:10.9 23:03:10.0 22:42:23.5 08:54:54.8 08:25:42.2 02:40:49.0 02:18:45.9 07:44:33.1 07:29:02.1 02:05:11.5 17:34:08.1 13:11:17.4 +28:06:29 +28:00:53 +28:05:30 +27:59:50 +28:00:47 +27:56:28 +27:58:33 +27:56:07 +28:03:25 +27:56:34 +27:59:35 +28:02:31 TABLE 3 d 4.3 2.6 8.9 8.8 5.8 8.8 7.9 5.2 5.1 9.0 11.l 1.2 d F5 MO M8 K7 K2 KO K0 K7 M7 III GO G5 K7 2 22 39 3 2 3 5 7 7 6 3 18 2 BD +27°4614 ß Peg BD Peg BD +28°2780 ß Com p Cnc ß Gem see Table1 (p Cnc 65 Gem BD +27°420 BD +27°329 Vol. 94 19 94ApJS. . .94. .749K jects, wecancomparetheentriesinTable4tolistingoflate judge theinternalcompletenessofselectingthesereddestob- exclusion fromTable4demonstrates thatthederivednumbers dicted (R—I)envaluesuggests adistanceof54pc.Thisisone barely brighterthanthe19.0 mag completenesslimit.Thepre- these fallswithinthe100pcsample.Forotherobject, the tions giveRen^19.4(fainterthantheadoptedcompleteness for thefaintestbinsshouldbe takenaslowerlimitsonly. of thetworeddestdwarfsdiscovered intheCTIstrip,andits limit)—the resultingvaluesof(7?-7)^suggestthatone of i^cri? °fwhich10havebeenincludedinTable4,two fall M7 dwarfCTI115638.4+280000,thepredictionofRen = and measured7^magnitudes.Forthreeofthese,thepredic- adopted limitingmagnitude,andonefallsinanexcluded beyond the100pccutoff,oneisfainter(Ren=20.02)than the magnitudes canbeestimatedfromtheobservedspectraltypes range ofrightascension.Fortheremainingfourobjects, Ren with nondetectionsatRen.Intotalthereare18objectsin dwarfs inTable1,verifiedspectroscopicallyandselectedby (R -7)and/or(VcolororbybrightTendetections been acquired,butbecauseitsfinderchartshowsittobefree reflect themeancolorsofgiantsovertheirlightcurves.) Table 1withtypeM6orlater.Ofthese,14weredetected at from sourcesofphotometriccontamination,itisretained.To been observedspectroscopicallyandhavedwarfspectraltypes sion ofmanymorenightsdataintothedatabases,thesewill ple) simultaneously,itisnotclearwhatthe(B—1)^values able starsandbecauseCTIcannotacquireB/(forexam- giants isnegligible.(BecauseMarehigh-amplitudevari- however, spectroscopyhasshownthatcontaminationby themselves fromthedwarfsonthisplot.Asnotedpreviously, of M6orlater.AspectrumCTI022000.5+275933hasnot for theseobjectsactuallyrepresent.Overtime,withtheinclu- cally identifiedgiantshavingR>12.0donotdistinguish which showsthe(7?-/)versus(Rdiagramfor have alargescatterof(B—7)^values,andtwospectroscopi- (open triangles)listedinTable1.Thedwarfsareshownto the objects.Thissecondsequence,however,doesnotrepresent spectroscopically observeddwarfs(filledcircles)andgiants 18.8 indicatesthatitshouldhavebeendetected,thoughthis is a sequenceofgiantsorsubdwarfs,asverifiedbyFigure\2b, criCTI objects thathavebeenremoved. circles representobjectsthatareretained,andtheopenindicate of objectstobeusedinconstructiontheluminosityfunction.Thesolid m cn No. 2,1994LUMINOSITYFUNCTIONATENDOFMAINSEQUENCE Of thenineobjectsinTable4withM>12.0,eighthave /kc Fig. 11.—The(V-1)^vs.R7)^diagramforthefinalselection © American Astronomical Society • Provided by theNASA Astrophysics Data System -1 h hm hm the NLTTCatalogue(Luyten 1979,containingobjectswith resulting 60objectsaregiven inTable5.Column(1)givesthe p> 0''18yr)hasbeenused togeneratealistofproper- h motion-selected objectsthatshould liealongtheCTIstrip.The ture confirms,theSunresides—10-40pcnorthofgalactic midplane. nificant. Nonetheless,astheseresultssuggestandthelitera- southern subsampleswouldnotbeconsideredstatistically sig- ß =300pc.However,thedifferencebetweenournorthern and distance northofthemidplaneifß=350pc,ord35 pc if determination of*=givesavalueof¿/q41pcastheSun’s If thisequationissolvediteratively,itcanbeshownthatour tudes. Itcanbeshownusingequation(3)that 0 Galactic latitudes(23will -30° )and27inanequallysizedarea(730), 0 c0 adc2 e[(ad —1)+1]2 c External Checks (10) 761 19 94ApJS. . .94. .749K 234725.1+280306 233855.8+280517 233452.3+275955 230637.3+280228 180525.2+275914 171417.4+280630 165052.8+275958 161117.0+280426 151814.8+280548 095541.2+280148 083524.2+280412 075350.3+280306 144708.9+275947 125417.4+280002 074104.7+280143 144455.1+280618 142531.5+280033 115350.7+280342 115339.5+280332 022228.2+275853 015723.6+275946 112959.7+280044 105707.5+280223 104642.9+280435 103555.5+280005 101912.3+280028 015115.8+280458 014344.1+280344 010332.0+280234 002151.7+280450 001956.9+275927 233843.5+280219 232016.4+280607 231028.2+280452 225113.8+280022 083520.9+280004 072709.4+280352 020859.6+280504 093631.3+280237 011557.5+275930 011544.7+280414 003257.9+280102 003238.9+280229 224754.6+280029 232230.1+280303 175443.4+280405 171834.3+280550 170759.1+280555 154107.1+280508 145115.0+275902 140051.1+280653 135842.2+280642 114014.1+280624 111007.3+275952 094720.8+280132 082957.2+275934 081630.4+280502 134024.0+280508 023847.2+280001 CTI Name 165812.6+280131 160042.7+275927 155023.4+280613 154930.3+280216 124540.8+275915 105543.8+275850 101140.7+275859 American Astronomical Society •Provided bythe NASA Astrophysics Data System 13.15 14.69 14.57 13.18 15.17 13.56 15.16 13.74 14.46 14.79 14.82 15.03 15.05 13.58 15.01 14.70 14.17 14.76 15.16 15.16 14.71 15.23 14.63 15.16 14.85 13.58 15.05 14.72 15.37 14.71 15.25 13.62 14.40 14.50 14.02 14.01 13.02 13.51 14.85 13.24 14.81 13.96 14.55 14.16 13.92 14.49 14.19 13.57 14.39 14.73 14.71 14.79 12.97 13.59 13.14 13.73 12.82 13.01 13.37 13.60 Rcti (R-I)cti(V{BMj 13.49 14.06 13.32 13.89 13.88 12.75 k Objects UsedintheDerivationofCTILuminosityFunction 0.87+.01 0.97+.02 0.99+.05 0.95+.01 0.97+.03 0.96+.01 0.96+.01 0.97+.01 0.94+.02 0.89+.01 0.88+.01 0.95+.01 0.95+.01 0.91+.01 0.90+.01 0.99+.Ö1 0.88+.01 0.95+.01 0.92+.01 0.96+.01 0.91+.02 0.94+.02 0.96+.01 0.89+.01 1.00+.01 1.00+.01 0.99+.01 0.87+.01 0.99+.01 0.77+.01 0.82+.01 0.84+.02 0.73+.01 0.77+.01 0.86+.01 0.78+.01 0.78+.01 0.81+.01 1.00+.01 0.80+.01 0.84+.01 0.85+.02 0.83+.02 1.00+.01 0.79+.01 0.80+.01 0.84+.01 0.84+.01 0.82+.01 0.75+.01 0.84+.01 0.86+.01 0.81+.01 0.67+.01 0.61+.01 0.67+.01 0.67+.01 0.66+.01 0.64+.01 0.60+.01 0.69+.01 0.65+.01 0.63+.01 0.64+.01 0.69+.01 0.71+.01 2.38+.01 2.58+.01 2.63+.04 2.53+.01 2.75+.01 2.61+.01 2.57+.01 2.61+.01 2.60+.01 2.46+.01 2.46+.01 2.53+.01 2.54+.01 2.47+.01 2.44+.01 2.60+.01 2.45+.01 2.55+.01 2.48+.01 2.55+.01 2.59+.01 2.60+.01 2.47+.01 2.51+.02 2.55+.01 2.43+.01 2.57+.01 2.40+.01 2.56+.01 2.60+.01 2.63+.01 2.29+.01 2.36+.01 2.38+.01 2.25+.01 2.37+.01 2.29+.01 2.33+.01 2.29+.01 2.30+.01 2.36+.01 2.43+.01 2.39+.01 2.42+.01 2.41+.01 2.30+.01 2.37+.01 2.37+.01 2.32+.01 2.30+.01 2.25+.01 2.36+.01 2.41+.01 2.17+.01 2.05+.01 2.20+.01 2.18+.01 2.15+.01 2.13+.01 2.04+.01 2.12+.01 2.16+.01 2.09+.01 2.09+.01 2.17+.01 2.18+.01 (c) 9.012.0areshown bytheshadedboxes. used inconstructionoftheluminosity function(Table4).Objectswith tions areupdatedtoequinox1987.5coordinates(epoch umns (6)and(7).TheCTI“masterlist”isthensearchedfor the precessioncoefficientslistedinLang1980),1950posi- of theseobjects.Thesepredictedcoordinatesarelistedincol- proper motionaswellprecessionofthecoordinates(using proper motioninarcsecondsperannum.Incorporatingboth Luyten’s colorclassoftheobject;andcolumn(5)gives magnitudes aslistedintheNLTTCatalogue;column(4)lists LP orothernameoftheobject;columns(2)and(3)give Ikc 1987.5 )togiveapredictedCTIpositionaldesignationforeach Fig. 13.—Histograminrightascension ofthefinal134objectstobe ll.60i.25 15.25i.2777i9M6V0.46 12.53i.63 12.53i.71 12.67i.28 Mv 16.60i.78 86i29 16.80i.31 54i7 18.14i.87 5Ü19M8.5V0.89 16.60i.68 81Í24 16.06i.43 75il4 16.16i.75 98i31 16.56i.60 95Í25 k dist(pc) Sp.Type C 6 /_M =— (v^-) =0.74Í.38 (vh)- jA-) =0.48Í.27 — 0.58 M6.5 V— M6.5 V— M6 V0.70 M6 V0.17 M6.5 V0.42 M6 V0.94 M6 V0.86 = 0.46Í.16 = 0.89Í.15 v 19 94ApJS. . .94. .749K Object G 72-29 G 72-28 BD +27°262 LP 294-34 LP 298-38 LP 297-8 ß Gern G 100-36 LP 302-46 LP 300-18 LP 299-34 LP 298-47 LP 308-14 Ross 411 LP 301-16 BD +28°1779 LP 314-8 LP 313-5 Wolf 411 G 147-4 BD +28°1902 LP 315-63 LP 314-68 G 150-43 LP 322-403 LP 321-106 LP 319-8 LP 317-36 LP 317-5 G 168-23 LP 327-10 LP 325-29 LP 325-1 LP 324-30 BD +28°2242 LHS 2723 LP 322-1178 LP 321-218 LP 331-23 LP 331-4 LP 331-41 LP 333-8 LP 332-17 LP 332-10 G 184-30 LP 334-45 LP 334-3 LP 333-26 ß Peg LP 340-555 Ross 712 LP 343-42 LP 342-7 LP 345-43 LP 344-8 confirmed fromCTIimagestobethepropermotionobject(LP323-25 =LHS2723)inquestion. LP 346-14 LP 346-7 LP 345-49 LP 346-43 LP 346-50 d c b a Luyten1979appearstohaveoverestimatedthisobject’spropermotion. TheCTIstarlistedinthetablehasbeen InTable1. Valuesinparenthesesrefertophotometry. Predictedcoordinatesforepochandequinox1987.5. © American Astronomical Society • Provided by theNASA Astrophysics Data System 7.9 16.0 8.9 10.2 11.4 14.6 11.8 10.5 6.7 18.2 14.5 14.2 11.0 12.8 18.9 16.6 11.6 1.1 14.0 15.2 17.4 14.9 11.1 17.8 12.8 16.2 10.4 17.9 16.5 15.1 15.3 17.7 12.8 13.3 17.0 18.2 18.6 18.3 14.2 17.7 11.7 15.8 16.1 14.3 2.6 14.7 15.3 17.8 16.1 14.6 11.3 12.6 15.3 16.6 11.3 17.1 14.5 18.1 14.0 17.5 8.8 21.1 21.0 2.2 17.5 20.9 9.8 12.5 12.9 11.6 7.8 14.5 15.6 11.7 15.7 15.5 15.7 12.1 20.5 20.8 20.3 20.3 18.5 13.4 15.5 12.6 13.1 19.7 14.6 16.9 18.0 16.6 16.8 19.6 14.8 18.3 16.0 11.0 16.0 19.4 12.3 4.1 16.9 17.6 15.8 17.6 16.4 20.2 13.2 16.4 19.4 16.3 12.8 11.9 16.6 17.7 18.6 15.6 15.5 19.4 Stars fromtheNLTTCatalogThatShouldBeinCTIStrip m col k m k k k k G5 g G5 K0 f-g m-|- m m m m K0 m .212 m+ m Ml m k-m .196 G5 m .260 m .243 g k-m .183 k MO m .284 .190 .240 .240 .534 .192 .347 .205 .193 .223 .280 .625 .197 .305 .184 .203 .227 .202 .186 .193 .238 .198 .182 .223 .210 .390 .500 .228 .185 .245 .222 .377 .186 .180 .261 .220 .187 .220 .237 .287 .278 .241 .244 .240 .298 .297 .270 .237 .229 .222 .281 .187 .198 .206 .232 a RA(1987.5)Dec 03:11:49.2 02:54:56.3 02:49:29.3 02:08:59.9 01:42:58.4 01:42:56.4 01:38:53.7 01:00:04.6 05:34:13.5 04:40:41.1 03:57:50.4 03:35:33.0 09:02:10.7 07:44:33.6 07:02:44.3 05:47:25.4 09:48:13.4 09:36:06.6 09:28:38.2 10:17:10.5 10:53:45.5 10:45:59.2 10:34:08.7 12:40:49.3 12:23:01.3 11:38:46.7 10:59:46.0 15:04:58.1 14:11:11.2 13:49:10.4 13:20:14.8 13:15:40.1 13:01:41.7 12:41:53.9 16:58:13.1 16:49:57.5 16:00:42.3 14:20:53.4 13:53:47.3 13:35:06.0 21:38:59.2 21:04:49.4 17:14:17.8 17:04:35.6 22:27:41.4 22:17:22.2 17:54:43.9 17:41:21.0 17:18:34.4 23:03:10.2 18:30:02.1 18:05:58.1 23:07:06.9 18:49:25.9 18:48:17.5 23:20:16.3 23:10:14.1 23:21:33.2 23:31:33.5 23:34:51.8 27:59:43 28:04:48 28:03:30 28:05:08 27:59:25 27:59:37 28:02:54 28:05:22 27:59:25 28:01:07 28:06:08 28:04:44 28:03:26 28:02:17 28:03:09 28:01:42 28:06:33 28:04:36 27:58:32 28:01:34 28:02:08 28:03:37 28:06:16 27:59:08 28:00:14 28:01:19 28:02:36 28:02:00 28:02:32 28:01:39 28:04:16 27:59:03 27:59:43 28:04:07 28:02:08 28:03:55 28:02:28 28:01:31 28:06:41 27:59:26 28:06:29 28:03:16 28:04:04 28:01:26 28:05:48 28:05:29 28:05:06 28:04:17 28:05:07 28:04:57 28:04:40 28:02:24 28:00:56 28:02:54 28:02:25 28:01:35 28:06:08 27:59:57 28:02:02 28:00:39 TABLE 5 c CTI Name 014256.7+275937 013853.9+280256 010005.0-1-275941 031149.0+280442 025456.4+280449 024929.6+280328 020859.6+280504 014257.9+275925 053413.5+280529 044041.1+275919 035750.4+280105 033533.4+280608 092838.3+280629 090210.4+280434 074434.0+280331 070244.0+280215 054725.2+280312 094811.7+280337 093606.5+280149 (not found) 104559.5+275829 103407.9+280137 101710.9+280213 113846.6+280016 105945.8+280120 105345.9+280235 124049.5+280231 135347.7+280419° 134910.5+275904 132017.4+280347* 131541.3+280227° 130144.9+280346 124154.1+280620 160042.7+275927 150457.9+280202 142053.4+280234 141111.3+280141° 133505.7+275945 222741.1+280253 221722.6+280441 213859.6+280219 171417.4+280630 170435.1+280315 165812.6+280131 164956.9+280642 230706.6+280135 230310.5+280045 (not found) 180558.5+280419 175443.4+280405 174121.4+280126 171834.3+280550 232016.4+280607 231013.8+280223 183002.4+280506 232133.4+280040 184925.5+280459 184817.9+280533 233452.3+275955 233133.1+280158 Rcti <10.02 (<11.1) <10.18 <10.84 <10.50 15.18 (14.65) (<11.6) (13.32) (<10.8) 13.77 13.57 <8.61 17.47 17.25 (<9.3) 11.40 13.52 <11.88 14.19 16.03 16.75 12.24 17.06 14.46 (<11.5) 17.02 13.88 14.69 <10.90 15.64 16.76 15.35 12.82 16.32 17.68 17.84 17.35 13.73 17.15 (15.14) <11.70 15.66 14.85 13.56 13.75 16.35 15.51 13.51 <10.00 10.36 14.45 17.15 15.78 13.62 16.59 16.35 13.18 0.19+.01 0.64+.13 (R —I)ctiNote 0.82+.01 0.21+.01 0.06+.01 0.26+.01 0.11+.01 -0.07+.01 0.63+.08 0.80+.06 0.72+.01 -0.27+.03 0.15+.02 1.41+.08 0.03+.06 0.38+.02 1.02+.09 -0.39+.06 -0.27+.01 0.62+.05 0.05+.02 1.11+.03 -0.02+.03 0.14+.10 0.67+.01 0.92+.08 -0.36+.01 0.86+.01 0.96+.01 0.67+.01 1.34+.04 0.77+.01 1.20+.03 1.21+.01 0.29+.01 0.09+.11 1.00+.03 1.43+.08 1.60+.06 0.60+.04 1.15+.02 0.82+.01 0.99+.05 1.11+.12 1.35+.05 1.08+.04 too bright too bright too bright d=176±ll pc too blue too bright in Table4 RA excluded RA excluded RA excluded too bright d=188±20 pc too bright too bright RA excluded RA excluded RA excluded too blue too blue too blue too bright d=141±9 pc too blue RA excluded too bright too blue d=102±7 pc too bright in Table4 d=101±6 pc too blue d=125±17 pc in Table4 too blue d=118±7 pc in Table4 too blue in Table4 too blue in Table4 d=145±8 pc d=315±39 pc in Table4 in Table4 too blue in Table4 RA excluded RA excluded too bright RA excluded RA excluded RA excluded RA excluded RA excluded in Table4 d=170±31 pc d=252±23 pc in Table4 d=125±10 pc in Table4 19 94ApJS. . .94. .749K photometric reductionsisnegligiblysmall.Themainreason tion surveys.Therefore,thepercentageofobjectswhichshould dicted positionhasamagnitudeofonly=10.8.Thereis for missedobjectsistheincompletenessatveryfaint(Ren> have beendetectedbytheCTIbutwhichweremissedduring detected, with—100%success,objectsfoundviapropermo- is usedintheconstructionofCTIluminosityfunction little doubtthatstarsthisbrighthaveactuallybeen“missed.” photometry routines,andthesegmentfallingnearestpre- gle entities.Forexample,ßGemisbrokenintomany CTI. Ofthetwonotdetected,Wolf411(m=11.1)andLP tances of97,72,and53pc for bincentersofM=12.75, tude ofRen=20.0isconsidered.Theseonlyprobeto dis- bins arenotcompleteto100pcevenwhenthelimitingmagni- the completenesslimitofstrip.Thethreelowestluminosity with Ren<12.0unreliable.ThebincenteredatM=12.25 luminosity function. case thederiveddistanceislisted).Intotal,thereare12objects ([R -/Jen<0.60),othersaretoobright(Ren12.0),and range ofR.A.beingusedfortheanalysis,othersaretooblue (Table 4)andifnot,whyitisnotused.Somefalloutsideofthe photometric segments(seeCawsonetal.1986a)bytheCTI ysis have,mostlikely,failedtodistinguishtheseobjectsassin- lems intheCCDsystemandsubsequentCTIphotometricanal- Columns (9)and(10)listthe(R-/)cnmeasure- and lying100pcawaywouldhaveRen=19.40,fainter than is marginallyincompletesinceanobjecthavingM=12.50 nonlinearity effectsintheCCDmakephotometryfor stars out of60thatsatisfythecriteriausedfordetermination others aredeterminedtobebeyondthe100pccutoff(inwhich ments fortheobjects. of eachsubtableinTable4.For arandomlydistributedsample luminosity function—which,forallbutthefaintestbins, isa the object’scalculateddistance,andFismaximum quantity, Visthevolumeofaspherehavingradiusequalto the objectanditspropagatederroraregivenincolumn(8), sponding CTInameoftheNLTTstaraslistedincolumn(8). objects neartheselocations,yielding(whenfound)thecorre- of stars,theF/Faveragein eachbinshouldbe0.5sincehalf volume of100pcradius. value ofVforwhichtheobjectwouldstillbeincludedin the and thevalueofVjV^isshownincolumn(9).Inthislast ( 7)aregivenincolumns6and).Theresultantdistanceto lute magnitudes/andFderivedusingequations(6) (V -f)crnand(R/jencolorsincolumns(3)-(5).Abso- each ofthe12half-magnitudebinsbetweenM=8.00to ( 1),theRenmagnitudeincolumn(2),and(R-/)cn> 340-555 (m=11.3)arebrightenoughsothatsaturationprob- 19.0) magnitudes. r /kc /kc 766 13.25, and13.75,respectively. /kc max 14.00. TheCTIdesignationforeachobjectisgivenincolumn max KC /kc r The firstbin,centeredatM=8.25,isincompletebecause Column (11)ofTable5givesanoteindicatingiftheobject The averageV/Fvaluesfor eachbinarelistedattheend In summary,thisexternalcheckshowsthattheCTIhas Of the60objectsinTable5,58wereclearlydetectedby Table 4ispresentedasacompendiumofsubtables,onefor /kc max 4.4. ResultingCTILuminosityFunction © American Astronomical Society • Provided by theNASA Astrophysics Data System KIRKPATRICK ETAL. 3 a a a a M bin.Ford=100pc,thevolumesearchedis2772pc. This istabulatedinTable7andshowngraphicallybythe 4, theCTIluminosityfunctioncanalsobeconstructedatV. bols), wheretheerrorbarsrepresentsquarerootof solid symbolsinFigure\4b. number ofstarsineachbin.UsingthedatapresentedTable out to100pc,thesebinssamplesmallervolumes. probed byeach,andthelogarithmofobservedluminosity in eachbinissummarizedTable6,alongwiththedistance which containsonlyonepoint.Thenumberofobjectsfound the binshaveK/F—0.5,withexceptionoffaintest, Since theobjectsoflowestluminositycouldnotbedetected function 4>,inunitsofnumberpercubicparsecunit distributed orisincomplete.Withintheerrors,however,allof ber isnotnear0.5,thenthesampleeitheruniformly volume, andtherestshouldheinfartherhalf.Ifthisnum- of theobjectsinbinshouldlienearerhalf M ^14.0(M15.5to18.0),asrepresented A/ <10.0(12.0M13.0)witharatherrapiddecline calculated, theMalmquistcorrection,whichdependsupon this incontextwithMdwarfspectroscopicclassifications,Ta- by thelower-limitpointsatfaintestmagnitudes.Toput toward M^12.0(A/15.5).Thereisalsoevidencefor first andsecondderivativesof4>(M),canbeappliedtode- Once the“observed”luminosityfunction4>(M)hasbeen Ishida, &Peacock(1989)andLeggettHawkins(1988). a fulldescriptionoftheMalmquistcorrections,seeStobie, have notbeencorrectedfortheMalmquisteffectandbias.For the dipinluminosityfunctionoccursataspectraltypeof and (7).Thisresultingrunofspectralclasswithabsolutemag- ble 8hasbeenproducedbytakingaweightedaverageofthe(R converting thesetoabsolutemagnitudesusingequations(6) an increaseinthenumberofobjectsfromM^12.0to Leu =20.0,onemagnitudefainter thantheadoptedcompletenesslimit; nitude isshowngraphicallyinFigures14aand14Z?.Notethat derived densitiesarethuslowerlimits. — /)colorsateachspectralhalfsubclassinTable1then /kc -M6 V. max obs /kcFkcvc /kcVyíc /kcFkc obs obs 13.75 153 12.75 397 11.75 1100 11.25 5100 10.25 22100 /lcc 13.25 072 12.25 3100 10.75 4100 CTI 9.75 29100 9.25 31100 8.75 22100 8.25 >13100 a The luminosityfunctionisshowninFigure14¿z(solidsym- As presentedabove,theluminosityfunctionsinFigure14 These luminosityfunctionsshowapeakintherange9.0< Objectsinthesebinsareincluded downtoalimitingmagnitudeof T// Number(pc)log$^ kcobs The CTILuminosityFunctionat/ TABLE 6 >-2.63 0.54>-2.68 >-2.67 0.55>-2.53 >-2.03 0.13>-2.02 >-2.32 0.80 -2.44 0.24 -1.80 0.11 -3.14 0.27-3.60 -2.54 0.17-2.82 -1.80 0.11-1.81 -1.68 0.10-1.69 -1.65 0.10 0.91 Vol. 94 19 94ApJS. . .94. .749K lower-limit points.TheerrorbarsrepresentthePoissonerrorsineachbin. and trianglesshowthedatafromTables67,wheredenote tude errorsforthefaintestbinaresufficientlylargethataccu- dwarfs, thecorrectionissosmallthattwosymbolsaresuperposed. Also shownarethecorrespondingdwarfspectralclassestakenfromTable points inFigures14aand146. Becausethesecorrectionsare corrected pointsfallwithin the errorbarsofobserved luminosity function,asevidenced bythefactthatallof ( solidcirclesandtriangles)withtheMalmquist-correctedlumi- and 146comparethe“observed”CTIluminosityfunctions given inthefinaltwocolumnsofTables6and7.Figures 14a ward- andcentral-differenceformulasgiveninConte& de tives inequation(11)havebeencomputedbyusingthe for- where A/istheabsolutemagnitudeandu^istypicalerror «Êtm* =$- tions arenegligible. When comparedtothePoissonerrorsineachbin,theseMalmquistcorrec- for theotherbinsdonotsignificantly altertheshapeof rate Malmquistcorrectionscannot beapplied.Thecorrections nosity functions(Sw—solidsquares).Theabsolutemagni- Boor (1980).Valuesforthequantitiesat/(0)andV(b).Solidcircles © American Astronomical Society • Provided by theNASA Astrophysics Data System /i ^irv\^^obs.d 2 (^) LUMINOSITY FUNCTIONATENDOFMAINSEQUENCE 2 M M, v (0.6 In10)$ obs , (ID 8 2 2 with uncertainphotometryorspectral types(notedbycoloninTable1) M5 V5 M3 V10 their luminosityfunctiononlyatÆ)withR-/astheprimary have notbeenused. M6.5 V3 Spectral TypeNumber{R-T)^Af the 84.7degsurveyofHawkins&Bessell1988,whotabulated M8.5 V1 M6 V9 M5.5V 16 M4.5 V11 M4V 12 M3.5 V6 M2.5 V6 Ml.5 V5 Ml V3 Figure 14a.TheLeggett&Hawkins(1988)determination M2 V2 MO V3 K7V 3 selection criterion.ThelimitofthesurveywasRæ20,with used a28degfieldattheSouthGalacticPole(asubsampleof Hawkins (1988)overplottedonourluminosityfunctionfrom tion($). lows willcontinuetorefertheobservedluminosityfunc- negligible whencomparedtotheerrors,sectionwhichfol- 5. COMPARISONOFTHISLUMINOSITYFUNCTIONTOOTHERS Æen =20.0,onemagnitudefainterthantheadoptedcompletenesslimit; each case,thebincenterisgiven. derived densitiesarethuslowerlimits. /icc obs 10.25 18.00 17.00 16.00 15.00 13.25 12.75 12.25 11.75 11.25 10.75 14.00 8 b a Numberofobjectsusedtocompute theweightedaverages.Objects Figure 15showsthe/-bandluminosityfunctionofLeggett& Objectsinthesebinsareincludeddowntoalimitingmagnitudeof Thefirstsevenbinsare0.5magwide;thelastfive1.0wide.In Average ColorsandAbsoluteMagnitudesfortheDwarfs V 5.1. ComparisontoOtherPhotometricallyDerived KC The CTILuminosityFunctionatV Number ;>6 28 19 16 18 18 4 6 2 9 7 1 Luminosity Functions from Table1 b TABLE 8 TABLE 7 b b 100 100 100 100 (pc) 100 100 100 100 100 100 60 90 0.72 8.5010.85 0.23 6.698.34 0.55 7.8910.00 2.30 13.5618.13 0.81 8.8111.29 0.62 8.1210.33 0.53 7.829.91 0.30 6.958.70 1.87 12.2716.23 1.74 11.9015.68 1.55 11.2914.80 1.50 11.1114.55 1.34 10.5913.80 L19 10.1013.11 1.00 9.4712.22 >-2.70 >-2.78 >-3.14 ^-2.36 log $01 -2.66 -1.86 -2.60 -1.94 -1.70 -1.89 -1.89 -2.19 0.59 0.26 0.12 0.87 0.59 0.15 0.10 0.10 0.11 0.12 0.13 0.14 logS* ^-2.39 -2.70 -2.60 -1.86 -1.95 -1.89 -1.69 -1.89 -2.15 767 19 94ApJS. . .94. .749K 2 2 take amuchlargerphotographicsurveyusingplatesfromthe and theotherfallingatZ>^+55°.Theprimaryselectioncrite- bin. Thispreviousuncertaintyabouttheupturnprompted 270 deg,withroughlyhalfofthesurveyfallingatZ?^-50° ongoing POSS-IIsurvey.TheTinneysurveycoversanareaof Tinney, Reid,&Mould(1993)andTinneytounder- depend stronglyupontheexistenceofasingleobjectinlast tudes fainterthanM>16. ( 1988)andtheReid&Gilmore1982)luminosityfunctions lower limitssetbyoursevenlowestluminosityobjects(Tables graphic F-/astheprimaryselectioncriterion.The tion fromFigure14b.TheReid&Gilmore(1982)surveycov- Mj> 12. 6 and7),theupturnsseeninbothLeggett&Hawkins agreement, withbothresultssuggestinganupturnatmagni- demonstrates, thesetwoluminosityfunctionsareinexcellent completeness Emitswere/^18.0andFæ19.5.AsFigure16 ered 18.24degtowardtheSouthGalacticPoleusingphoto- good agreementbetweentheirresults,basedonphotographic of Reid&Gilmore(1982)overplottedonourluminosityfunc- plates, andours,basedonCCDphotometry.Bothluminosity functions showevidenceforanupturnatluminositiesof completeness downtoRæ19.AsFigure15shows,thereis apparent increaseatthelowestabsolutemagnitudes. Galactic Pole(opensquares).Notethatbothdeterminationsof$showan bols) withtheLeggett&Hawkins(1988)luminosityfunctionatSouth v parent increasein $forM>16. Galactic Pole{opensquares).Note thatbothdeterminationsshowanap- bols) totheReid&Gilmore(1982) luminosityfunctionattheSouth 768 v Whereas theupturnseeninourdataisindicatedby Similarly, Figure16showstheF-bandluminosityfunction Fig. 15.—ComparisonoftheCTIluminosityfunctionatI{solidsym- Fig. 16.—ComparisonoftheCTI luminosityfunctionatV(solidsym- 25 2 -r -r ï$ : ïï**í 8 9101112131415 © American Astronomical Society • Provided by theNASA Astrophysics Data System • ^=Thispaper □ =LeggettàHawkins(1988) M, KIRKPATRICK ETAL. low-luminosity objectswithinafewparsecsoftheSunand differences whichmightexistbetweenthespacedensitiesof space densitiesforamoredistantsample.Themostrecent are oftencomparedtothecensusofnearbystarssearchfor (Mboi >12.0)magnitudes.Tinney’s Malmquist-correctedluminosity the tworesultsareverysimilarat both brighter(M^<10.5)andfainter squares). Disagreementisseenin the range10.5<12.0,although symbols) withthatofTinney(Tinney etal.1993andTinney1993—open function, givenbytheopencircles, resolvessomeofthisdisagreement. change someofhisvaluesbylargefactors.Weconclude, cally afiectthetrueshapeofhisluminosityfunctionand large (Tinneyetal.1993,thoughthesecorrectionsareignored luminosity functionforM>12{M16;>12). therefore, thatTinney’sdatadonotruleouttheexistenceofan in subsequentanalysisandTinney1993)—theydramati- beyond ^11.5,itappearstoturndownagainby quist-corrected luminosityfunctiondoesexhibitanupturn tion accordingtoTinney1993.)AlthoughTinney’sMalm- I -Kphotometry,donotneedsignificantMalmquistcorrec- 5.2. ComparisontotheLuminosityFunctionofNearbyStars because thereisnoprecedingdip!)Tinney’sownMalmquist than doestheCTIderivation.(Inessence,thereisnoupturn upturn atlowluminosities.Rather,ourdatasupportarising should benotedthattheresultsfor>12.5,derivedfrom agreement, asshownbytheopencirclesinFigure17.(It corrections bringthetwoluminosityfunctionsintobetter an upturnbecausehisluminosityfunctionpredictsmany the surveyresultspresentedinFigures15-17.Hedoesnotsee more objects—byafactorof3-12—with11.0<12.5 predicted atthelowestluminositiesisverysimilarforeachof evidence foranupturn,itisclearthatthenumberdensity and thoseofTinney.AlthoughTinneystatesthatheseesno Table 9. BCj versusM,relationtabulatedinBessell(1991),which ties. Acomparisonofourluminosityfunctionwiththat Values forourderivedluminosityfunctionataregivenin agrees wellwiththerelationgiveninMonetetal.(1992). Tinney isshowninFigure17,wherewehaveconvertedtheMj try wasacquiredtodefinethesampleatlowestluminosi- values ofTable4intobyusinglinearinterpolationsthe 13.5. TheMalmquistcorrectionsfortheTinneydataarevery 7v non isphotographicR-/,althoughsupplementalKphotome- -e- o> o -2.5 The resultsofaphotometricallyderivedluminosityfunction Fig. 17.—ComparisonoftheCTI luminosityfunctionat{solid Figure 17showsmajordiscrepanciesbetweenourresults -2 i 1■1-X_ = Thispaper = Tinneywith = Tinney Malmquist correction o Mbol I $ O 13 14 Vol. 94 19 94ApJS. . .94. .749K No. 2,1994 a a completeness limit;deriveddensitiesarethuslowerlimits. tude ofÆer,=20.0,onemagnitudefainterthantheadopted 12.25 494>-2.46 11.75 1100-3.14 11.25 5100-2.44 10.75 11100-2.10 10.25 31100-1.65 12.75 154>-2.34 9.75 38100-1.56 9.25 28100-1.69 8.75 >13100>-2.03 a Objectsinthesebinsareincludeddowntoalimitingmagni- Afbo, Number(pc)log3> obs The CTILuminosityFunctionatA/^, American Astronomical Society •Provided bythe NASA Astrophysics Data System TABLE 9 GL 873 GL 388 GL 876 GJ 1245B GL 166C GJ 1245C GJ 1245A GL 687 GJ 1002 GL 83.1 GL 473A GL 234B GL 234A LHS 292 GL 473B GL 628 GL 860B GL 860A GL 54.1 GJ 1111 GL 273 GL 725B GL 725A GL 15B GL 15A GL 866A GL 447 GL 65A GL 866B GL 905 GL 65B GL 411 GL 406 GL 699 Object Luminosity FunctionDataforObjectswithM^8.0,b>-20°,andd5.2 7 g e 1 h f d c b a BasedonA/=1.71,AH1.66, andAK=1.51fromHenry1991. BasedonAJ=0.63,AH- andAK=0.63fromLeinertetal.1990. BasedonAJ=1.26,AH1.08, and AK=1.03fromHenry1991. BasedonA7=0.13,AH0.21, andAK=0.33fromHenry1991. BasedonAJ=1.19,AH1.14, andAK=1.37fromHenry1991. BasedonAJ=0.38,AH0.30, andAK=0.40fromHenry1991. Spectraltypesareonthesystem of PaperIandaretakenfromHenryetal.1994. TrigonometricparallaxesfromGliese&Jahreiss1991. PhotometryfromLeggett1992. LUMINOSITY FUNCTIONAT a 7.57 6.81 8.32 7.45 9.81 joint 6.72 9.17 8.92 joint12.46 8.06 joint 7.40 6.91 joint 8.90 10.27 7.16 7.13 6.44 8.25 5.94 8.62 joint 8.14 8.31 joint 8.84 5.32 9.39 6.77 11.20 I 10.16 10.53 Parsecs (WhiteDwarfsExcluded) a 9.32 9.22 9.59 joint 9.86 9.68 8.90 10.26 11.19 8.08 10.18 14.00 13.41 joint 15.60 12.29 11.08 joint 9.55 13.76 10.08 12.05 7.47 14.79 V 11.07 12.33 joint 11.12 12.00 joint 12.29 13.45 6 0.1970±0.0025 0.2113±0.0048 0.2120±0.0043 0.2039Í0.0028 0.207Ü0.0025 0.2120±0.0043 0.2120±0.0043 0.2127±0.0020 0.2238±0.0029 0.2128±0.0033 0.2210±0.0036 0.2322±0.0043 0.2322±0.0043 0.242Ü0.0017 0.2421±0.0017 0.2447±0.0063 0.2519±0.0023 0.2519±0:0023 0.2644±0.0020 0.2674±0.0030 0.2758±0.0030 0.2861±0.0018 0.2861±0.0018 0.2895±0.0049 0.2895±0.0049 0.2943±0.0035 0.2943±0.0035 0.3011±0.0019 0.3807±0.0043 0.3807±0.0043 0.3156±0.0016 0.3973±0.0018 0.4183±0.0025 0.5453±0.0010 7T (arcsec) TABLE 10 3 END OFMAINSEQUENCE been de-convolvedintotheirseparatecomponentsusingthe observations oftheinfraredmagnitudedifferencesforeach magnitude differencerelationsderivedinPaperIVandspeckle The IandVmagnitudesfortheclosebinariesinlisthave GL 412AandB,originallyincludedinthe1986census,now have parallaxvaluesplacingthembeyondthecutoff,andGL Dahn, Liebert,&Harrington(1986).GJ1116AandB 866 isnowlistedasadoublestar(Henry&McCarthy1990). Mj >8.0isgiveninTable10,wherewhitedwarfshavebeen taken fromLeggett(1992).Theresultinglistofobjectswith to ô>-20°becausethecensusisundoubtedlystillincomplete excluded. compendium ofnearbystars,thatGliese&Jahreiss(1991), in thesouthernhemisphere.Theresultantvolumesampledis laxes Tr>0T1923{d<5.2pc).Thislistingisfurtherrestricted is usedtoselectallknownobjectshavingtrigonometricparal- 395 pc,/-bandandF-bandphotometryforthissampleare The luminosityfunctionwithin5.2pcwasfirstreportedin b 1 e c d d 9.04 8.36 9.90 9.07 8.36 9.34 9.15' 9.27 11.90 11.67* 11. b6 9.41 8.25 13.25* 11.80 12.92 10.92 11.46' 12.35* 10. m 8.72 10.69' 8.32 11.04 12.73 M/ 10.56 12.17 11.39 10.53 11.34 12.13 11.81 12.50 10.45 h e d d 10.87 11.73 12.77 11.80 15.63 17.53*' 15.15* 10.86 17.32 is.oe* 15.40 14.04 15.03 16.33* 13.05* 12.02 13.92' 11.74' 14.19 M 11.97 16.99 11.96 10.39 11.18 13.38 16.13* 15.00 13.51 14.79 15.87 15.47 10.47 16.56 13.23 v c M3.5 V M3 V M4.5 V M3.5 V M6 V M3 V M5.5 Vcomp. M5.5 V M6.5 V M4.5 V M4.5 Vcomp. M5.5 Vcomp. M3 V M4 V M3 V M6.5 V M3.5 V M4.5 V M3.5 V Ml.5 V M3 V M3.5 V M5 Vcomp. M4 V M5.5 V M4 V Spec. Type M5.5 V M6 V M2 V M6 V 769 19 94ApJS. . .94. .749K as amoredistantsamplederivedphotometrically {opencirclesanddashed and dot-dashline),thenearby luminosityfunctionwhenrecomputed and solidline),thenearbyluminosity functionofTable10{opensquares jects inaphotometricallyderivednearbysampletohaveesti- line). Seetextfordiscussion. are usedinthe100pcsample.Third,scatterabsolute allaxes tocomputedistances,whereasphotometricparallaxes distance fromtheSun—if5.2pcsampleweremovedto79 an excessoflow-luminosityobjects. the nearbysampleandmoredistantonesthatrelyonphoto- sample), manyofthemultiplesystemswouldbeunresolvable. pc (thedistancecorrespondingtohalf-volumefora100 CTI sampleisbasedonavolumewithmuchlargeraverage magnitude versuscolorrelationwouldcausesomeoftheob- Second, the5.2pcsamplereliesonaccuratetrigonometricpar- investigated. Toconvertthisluminosityfunctionintoalumi- metric parallaxes.Hesuggeststhatthesolarneighborhoodhas the otherhand,modelseffectofunresolvedbinariesand fects mustbeconsidered.First,thephotometricallyderived nosity functionlikethatderivedfromtheCTIdata,threeef- finds thatthiseffectcannotreconcilethedifferencesbetween the differencebetweentheirluminosityfunctionsfornearby the luminosityfunctionisquitedifferentfromCTIdetermi- more distantsurveystorecognizeduplicity.Reid(1991),on magnitude-limited surveysisduesolelytotheinabilityof stars andluminosityfunctionsfoundduringmoredistant, Dahn etal.(1986)andHenry&McCarthy1990)arguethat solved primariesshifttolowerluminositybinsthemselves. panions arefound,whileloweringthebrighterendasre- easily resolvedinthenearbysample,andthistendstoraise faint endoftheluminosityfunctionaslowercom- nation. Onepossiblereasonforthisisthatbinariesaremore Poisson errorsareindicatedinFigure18. 8.5 to11.5withagradualdeclineMj=13.5.Thisformof source oferrorcomesfromthepaucityknownobjects— errors intheabsolutemagnitudeswillcorrespondinglybe derived absolutemagnitudes. given inthelastcolumnofTable10forcomparisonto small, makingtheMalmquistcorrectionnegligible.Thelargest nearby sample,thetrigonometricparallaxesaresowelldeter- Figure 18alongwiththeCTIresultfrom15.For pair, asquotedinthenotestotable.Spectraltypesarealso mined thattheLutz-Kelkercorrectionisnegligible,and 110 Fig. 18.—ComparisonoftheCTI luminosityfunction{solidsymbols To addressthisissue,the5.2pcsampleofTable10isre- The nearbyluminosityfunctionisvirtuallyflatfromMj= The resultingluminosityfunctionofnearbystarsisshownin © American Astronomical Society • Provided by theNASA Astrophysics Data System KIRKPATRICK ETAL. h 3 would addtwomorepointsatmost totheluminosityfunctiondescribed that thisobject’sphotometricallyderiveddistance,whichwouldbe an would havecompositephotometryinthemoredistantsample,itis likely derived photometricallycouldplaceitwithinthe5.2pcsample.GL 338 pc; becauseofitsproximitytothe5.2pccutoff,adistanceforthisobject does notaltertheconclusionswhich follow. below—one atmid-Mtypesandthe otheratearlyM.Exclusionofthese AB hasatrigonometricparallaxplacingitat6.2pc;becausethisbinary ing itoutsideofthesampleconsidered here.Regardless,thesetwosystems indicate thatthisderivedabsolute magnitude willlikelybeMj<8.0,plac- underestimate ofthetruedistance,wouldplaceitwithin5.2pc.The K7/ volve smallnumbers,suggeststhatthisdisagreementmaybea composite systems,togetherwiththefactthattheseresultsin- M0 spectraltypesofGL338A and BpresentedinPaperI,however, ties, and(mostimportantly)unresolvedbinarityareconsid- of binariesintheotherbinsis57%.Thispreponderance GL 473AB,GJ1245ABC,866and905.Thus, the bincenteredonM=11.5.For5.2pcvolume,CTI ered. and photometricluminosityfunctionsareconsistentwhenthe luminosity functionwouldpredictonlyoneobjectintheMj= the CTIluminosityfunctionovermostofrangeA/, that itpeaksatMj~9.5(liketheCTIluminosityfunction) spread ofagesandmetallicities,themeasurementuncertain- Kroupa, Tout,&Gilmore(1993).Theyfindthatthenearby although amajordiscrepancybetweenthetwostilloccursat and isloweratluminosities(alsoliketheCTIluminosity differs inshapefromthetruenearbyluminosityfunction forms oftheluminosityfunctionhasbeenperformedby 80% ofthese“objects”arecomposite—thehighestfrequency function). Infact,thisnewresultisinbetteragreementwith This resultisalsoshowninFigure18.newderivation are composites(consistingof12binariesand1triplesystem). thus contains28“objects”ofwhich15aresinglestarsand13 objects within100pcandwithMj>12.0fallintherange 0 < by theUSNO.PhotometryforGJ1005ABwastakenfrom taken fromLeggett(1992)orunpublishedphotometry Paper IV.No/photometrywasfoundforeitherG99-49orGL mere statisticalfluctuation. photometrically deriveddistancesplacednoneofthesewithin 338 AB,sotheseobjectsarenotconsideredfurther. of 25objectsbetween7and10pcwerealsoselected,butthe pc wasselectedfromGliese&Jahreiss(1991).(Asubsample to beconsidered;determinewhichcompositesystemsareno 5.2 pc.)Formostofthe7pcsample,Vand/photometrywas nitudes anddistances. single starorsystemneedtobeusedcomputeabsolutemag- a largerdistance;and{V-1)colors/photometryforeach longer resolvablethosestarsneedtobethoughtofasresidingat As aresultofthesethreeeffects,largervolumestarsneeds 11.5 bin,whereasfive“objects”actuallyfallthere:GL65AB, 7 of thevolumewillhaveestimatesplacingthemwithin5.2pc. mated distancesgreaterthan5.2pc,andsomeobjectsoutside 7 3 5.3. ComparisonofLuminosityFunctionswithb>0°to G99-49isanM4dwarfwhosetrigonometricparallaxplacesitat5.4 A cursoryglanceatTable4revealsthatmostoftheCTI Rigorous, in-depthmodelingofthebiasesinherenttoboth The photometricallyderivednearbyluminosityfunction To investigatethis,acompletesampleof74dwarfsoutto7 Ones withb<0° Vol. 94 19 94ApJS. . .94. .749K 8 9 h 2 jects forspectraltypesofM6Vandlater,althoughunlike tion limits.TheoreticalmodelsbyBurrowsetal.(1993)dem- to thebrowndwarflimitcontinuecool,reachingmain than 0.1Mqbegintobumhydrogen.Thosewithmassesdown dwarfs existbutthattheyhavecooledbeyondcurrentdetec- types laterthan—M6V,this scenariosupportsthemajorcon- onstrate thatatanageof~2X10yr,starswithmassesgreater Because theseabsolutemagnitudes correspondtospectral parts willhavecooledsufficiently tomakethemundetectable. Therefore, theapparentyouth ofobjectsfainterthan~ mass starsdonotcoolenoughtomakethem“undetectable.” sequence atanageasold1X10yr,buteventheselowest in Table4includesevenobjectsatsoutherlygalacticlatitudes Galactic latitudes.Moreprecisely,theentrieshavingM>12.0 and onlytwoatnortherlyGalacticlatitudes.Moreover,the R. A.<2.AsshowninFigure1,thiscorrespondstosoutherly ing, thetwoobjectsatnorthernGalacticlatitudesshouldnot area sampledbytheCTIis7.9degforb<0°and19.4 Figure 13.)Asimilardisparitybetweensouthernandnorthern even beincludedsincebothfalloutsidetheluminositybin b >0°,implyingthatthedensityoflow-luminosityobjectsis Although hecomparesthetwosubsamplestoshowthat ple dividedbetweensouthernandnorthernGalacticlatitudes. pended uponthevagariesofobservingschedulesandweather uniform sample(becausethespectroscopicobservationsde- Table 4,theentriesin1shouldnotbeconsideredasa southern objectsis3.5timeshigherthanthatofnorthernob- objects isseeninthedatapresentedTable1—thedensityof considered inTable4k!Seetheshadedbinshistogramof conditions). 8.6 timeshigherinthesouththannorth.(Strictlyspeak- population ofobjectswithascaleheight350pc.Clearly, density ofobjectsatsouthernGalacticlatitudesshouldonlybe plane oftheGalaxy(§4.3.2),equation(10)showsthat parison difficult. tion werenonuniformfromfieldtofield,makingsuchacom- selection criteriaforthelastfewbinsofluminosityfunc- virtually identical(Tinneyetal.1993),hedoesnotmakea derived luminosityfunctionsbrighterthan^12.0are been attainedaftermanyepochsofstarformationandsubse- kinetic energiesandanincreasedscaleheight. have tobeyoung;olderobjects,havinghadsufficientnumbers A populationofobjectswithsuchasmallscaleheightwould height muchsmallerthan350pc(althoughbetterstatisticsis objects withM>12.0{M15.5)exhibitanoverabundance similar comparisonatfaintermagnitudes(Tinney1993).His lier epochswouldhaveceasedatsomehighermasslimit. quent enrichmentbysupernovaejecta.Starformationat ear- enriched metallicities—metallicitiesthathaveonlyrecently could bethattheformationoftheseobjectsonlyoccursat objects maybesotightlyconfinedtothemidplane.First,it needed beforewecanaccuratelydeterminewhatthevalueis). far inexcessofthisfactorandmustthereforehaveascale of encounterswithothermatterinthedisk,willhavehigher 12.0 impliesthatthesearebrown dwarfs,whoseoldercounter- 7 ~ 1.1-1.2timeshigherthanthatatnorthernlatitudesfora No. 2,1994LUMINOSITYFUNCTIONATENDOFMAINSEQUENCE 7v Second, itcouldbethatolderexamplesoftheselateM The luminosityfunctionofTinneywasalsobasedonasam- Assuming thattheSunislocated~10-40pcabovemid- There aretwopossiblereasonswhytheselowluminosity © American Astronomical Society • Provided by theNASA Astrophysics Data System = hm -3 2 2 2 derived densitiesarethuslowerlimits. Rcti 20.0,onemagnitudefainter thantheadoptedcompletenesslimit; 2236 12.ThedashedlineinFigure19showsthe southern portion,whichshowsanincreasingdensityofobjects are youngandhaveasmallscaleheight. R =20.5(asopposedto<20fortherestofsurvey). 12.75 12.25 11.25 nosity functionsareplottedinNelson,Rappaport,&Joss sults oftheirsurveyindependentlysuggestthattheseobjects small velocitydispersionandlargevertexdeviation.There- Third, thedwarfsoflowest-luminositywerefoundtohavea ered onlyobjectswhichhadpreviouslybeendetectedalsoatR. (Likewise, coadditionsoftheCTIsurveyin§3.1.2produced They foundveryfewadditionallow-luminositystars,the prove uponthenumbersofverylowluminosityMdwarfs by Hawkins&Bessell(1988)asaresultoftheir84.7deg 10.75 10.25 The CTILuminosityFunctionat/BrokenintoNorthernand motion surveyusing/platesinanother28degsampleuncov- very fewlate-Mdwarfsnotalreadyfound.)Second,aproper others havingbeeneasilyidentifiedatbrightermagnitudes. found byextendinga28degareatolimitingmagnitudeof survey atsouthernGalacticlatitudes.First,theytriedtoim- and latermaybesubstellar. clusion ofPaperIV,basedondynamicalmassmeasurements of anumbermid-tolate-Mdwarfs,thatobjectstypeM7 1993.) Thesetheoreticalpredictionsalsosupporttheideathat 7 Q 7 9.75 9.25 8.75 c b2 111hm a2 hm1 8.25 Objectsinthesebinsareincluded downtoalimitingmagnitudeof Referstothe7.9degregionwith ¿?<0°(O^OR.A.300and Referstothe19.4degregionwith b>0°(726)$1 north 23 20 12 13 10 Southern GalacticPortions 0 0 0 0 0 2 5 TABLE 11 10 11 0 0 2 6 9 3 3 3 1 1 e e e e ^max 100 100 100 100 100 100 100 100 100 97 72 53 -2.60 -2.99 -2.22 -1.93 -1.99 -2.18 -2.29 >-2.08 ^-2.39 >-2.43 -2.90 -1.90 -2.60 -2.13 -1.95 -1.86 -2.43 'south 771 19 94ApJS. . .94. .749K 3 tively. binning (namely,themassbinsare0.05M©wide).Tables 12 M©. ThestarsusedbyHenry&McCarthy(1993)areshownto and 13arebasedonvolumesof2772395pc,respec- per unitmassintervalcubicparsec(log£).Table13 is Column (2)givesthenumberofobjectspopulatingthat bin, the centerpointofeach0.025M©-widebinforCTIdata. results listedinTables12and13.Column(1)ofTablegives plying thisrelationtothedatainTables4and10gives the be ofintermediatediskage,comparabletotheagesexpected similar, butthesmallernumberofobjectsdictatesacoarser and column(3)givesthelogarithmofnumberobjects trigonometric parallaxes—10ofthesehavemassesbelow0.20 pendent oftheory. for photometricallyselectedobjectsliketheCTIsample. Ap- on 73objectswithmeasureddynamicalmassesandaccurate mass functions.Thisrelationbetween2.0and0.08M©isbased Henry &McCarthy(1993)canbeusedtoconvertbothinto have beencomputedatL,themass-Mrelationderivedin sequence. Wecannow,therefore,deriveamassfunctioninde- tion ofthemass-luminosityrelationatendmain tion, haveconvertedthesemagnitudesintomasses.Recent to ~0.15Mfollowedbya dipandsubsequentrisetothe lowest luminositiesaresufficienttoaccountforthelocalmiss- (The formshownhereissometimes referredtoasthe“mass (Henry &McCarthy1993)nowpermitanempiricalderiva- and thenwiththehelpofatheoreticalmass-luminosityrela- at aparticularbandpassintobolometricabsolutemagnitude, mass functionhavereliedonconvertingabsolutemagnitudes has frequentlyrevertedtotheory.Otherderivationsofthe servational data,sotheconversionofluminositiesintomasses remained difficulttoanswerbecauseofapreviouslackob- ing mass.AsbasicasthisissueistoGalacticstructure,ithas smallest massesshown.Thisdip at~0.15M©isaconsequence spectrum.”) TheCTImassfunction showsafairlysteadyrise observations usinginfraredspeckleimagingtechniques predicted bythetheoreticalmodelsofNelsonetal.(1986)andnormalized so thatthebrowndwarfcontributionwouldaccountformissingmass. shows thecontributionofbrowndwarfstoluminosityfunctionas where arisingluminosityfunctionforMj>12isseen.Thedashedline in thenorthnoobjectsaredetectedwithMj>12,contrasttosouth, bols). Asinpreviousfigures,trianglesdenotelower-limitpoints.Notethat subsample {opensymbols)andasouthGalactic{filledsym- 772 K q Because theCTIandnearbyluminosityfunctionsof§5 The massfunctionsarepresented graphicallyinFigure20. Fig. 19.—CTIluminosityfunctionatIdividedintoanorthGalactic - •*=Southgalacticsample - =Nelsonetal.(1986)/ i I:i, □ a=Northgalacticsample 1 8 9 © American Astronomical Society • Provided by theNASA Astrophysics Data System I í }! 10 i « 11 12 1 13 H15 1 ■iliI I ! KIRKPATRICK ETAL. to thedataofFigure20givesa=—0.40±0.16forsolid tional work,however,stillneedstobedonedefinetheobser- Mq. Consideringtheuncertainties,theseresultsarenotincon- vational mass-luminosityrelationatverylowmasses. tion. Burrowsetal.(1993)haveshownthatthelowestmassof sistent withthelatestobjects’beingsubstellar.Muchaddi- a solarmetallicitystarfallsroughlyintherange0.074-0.080 these resultsshowamassfunctionthatisincreasingattheend luminosity functionatM=16correspondstoamassof0.099 to 0.2A/©,thenincreasesrapidlytowardlowermasses.Bothof of themainsequence.Itshouldbenotedthatdipin ±0.014 MqaccordingtotheHenry&McCarthy(1993)rela- function basedonthenearbysampleisbasicallyflatfrom0.5 of thefalloffinluminosityfunctionatM^14.Themass v v Fitting apowerlawoftheform a 0.4375 3-1.36 0.1375 4-1.24 0.1625 21-0.52 0.2125 9-0.89 0.2875 8-0.94 0.3125 10-0.84 0.3375 6-1.06 0.3625 5-1.14 0.3875 2-1.54 0.4125 3-1.36 0.4625 4-1.24 0.4875 2-1.54 0.0875 >9^-0.89 0.1125 6-1.06 0.1875 15-0.66 0.2375 17-0.61 0.2625 11-0.80 100 pccutoff. a 0.10 15 -0.12 0.15 7 -0.45 0.20 1 -1.30 0.25 4 -0.69 0.30 2 -0.99 0.35 1 -1.30 0.40 2-0.99 0.45 2-0.99 Thisbinisnotcompleteouttotheadopted Mass {M) Numberlog£ Mass (M) Numberlog| q 0 Mass FunctionBasedonCTIData Mass FunctionBasedonthe ^(M)oc(-) (12) Nearby Census TABLE 13 TABLE 12 a / M\ Vol. 94 19 94ApJS. . .94. .749K 3 -3 No. 2,1994LUMINOSITYFUNCTIONATENDOFMAINSEQUENCE Af >0.15Monly(a=-0.88±0.12),andthedottedlineisfitto (1993). Thefilledtrianglerepresentsalower-limitpoint.Opensquares per cubicparsec{filledcircles)derivedusingtheCTIluminosityfunction CTI data(a=-0.40±0.16),thesolidlineisfittohaving power-law fitsintheformofeq.(12),wheredashedlineisfitto show themassfunctionresultingfromnearbyluminosityof (Table 4)togetherwiththemass-MrelationofHenry&McCarthy gets, demonstratingthatthis sourceofcontaminationisalso data consideredfalloutsideof theGalacticplane.Inaddition, Appendix A.Becausesixofthesegiantsarefoundintherange charts, andlightcurvesofthesesevenobjectsarealsogiven in the CTIphotometry,havebeendiscovered;spectra,finder Table 10.ThePoissonerrorsineachmassbinareshown.Alsoshown spectroscopy hasrevealedtwo subdwarfsamongthe133tar- ber ofverylateMdwarfs.Follow-upspectroscopyhasidenti- nearby data{a=—0.59±0.22). negligible. selected sample.Sevengiants,allofwhichshowvariability in mine thecontaminationbynon-dwarfsinaphotometrically scopic follow-uponatotalof133CTIobjectsisusedtodeter- charts forthese18latedwarfsaregiveninAppendixA.Spectro- and lowestmassdwarfscurrentlyknown.Spectrafinder fied twelveM6s,fourM6.5s,oneM7,andM8.5.This last — 10°0.15M(solidUne),anda=-0.59±0.22 mass range.Low-luminosityMdwarfs,therefore,donotac- for starswithmassesbetween0.50and0.08M,whereasthe for theopensquares(dottedline).Thisillustratesamuchshal- 0 K Q 0 0 -3 The CTIdataarethenused toselectalarge,photometric Fig. 20.—Massfunction£inunitsofnumberperunitmassinterval Photometric datafromtheCTIareusedtouncoveranum- The CTImassfunctionpredictsadensityof0.012Mpc Q © American Astronomical Society • Provided by theNASA Astrophysics Data System 7. SUMMARY 2 sample ofMdwarfs.Thearealcoveragethissurveyis27.3 with ~100%success,asallpreviouslyknownpropermotion ward southernGalacticlatitudesthantowardnorthernones, databases. demonstrating, ashaveseveralrecentpublications,thatthe deg downtoacompletenesslimitofjR=19.0.Internalchecks objects catalogedoverthesurveyareaarefoundinCTI plane. ExternalchecksshowthattheCTIisdetectingobjects of thedatashowaslightlylargernumberearlyMstarsto- Sun issituatedafewtensofparsecsnorththeGalacticmid- the dipcorrespondingtoaspectraltypeof~M6.TheCTIdata tistics and,particularly,thespectroscopicverificationat ble. ApeakintheluminosityfunctionisfoundatM/^9.5 this areahasbeenpublishedinKroupaetal.(1993). tion totheluminosityfunctionfainterthan^12.0isthat work ofNelsonetal.(1986),whichshowsthemaincontribu- were substellar.Thislatterclaimissupportedbythetheoretical present instarformingregionsatearlierepochs)orthatthe pear eitherthattheoldermembersofthispopulationnever dwarfs. Presumably,thisisayoungpopulation.Itwouldap- that thesedwarfsoftypeM6andlaterarefoundpredomi- and southernGalacticcontributions,thetwoarefoundtobe intermediate magnitudescorrespondingtospectraltypesof (M æ12.5,A/bo!10.0),withasubsequentdecline,thenan the lowestmasses.Althoughthisupturnmaysignifyalarge inability toresolvemultiplestarscanexplainmanyofthe dif- counting ofuncertaintiesinthedistancedetermination of a rived fromthe5.2pccensus.Itisshownthatanaccurate ac- of browndwarfs. current detectionlimits—aswouldbetrueifthispopulation older membersofthispopulationhavesincecooledbeyond formed (theirbirthbeingprecludedbythelowmetallicities a scaleheightmuchsmallerthanthatofearly-andmid-M plane) suggeststhattheycompriseapopulationofobjectswith fainter magnitudesonlyexistsinthesoutherndata.Thefact virtually identicalbrighterthanMj=\l.0—buttheupturnat faintest magnitudesinoursurveyconfirmthattheupturnis Hawkins (1988)andReid&Gilmore1982).Thebettersta- are ingoodagreementwithpublishedresultsbyLeggett& upturn fainterthanMj«12.0(Mæ15.5,11.5)— ric magnitudes.Malmquistcorrectionsareshowntobenegligi- bility ofsuccess,looktoward southernGalacticlatitudes! dwarfs andverylateMdwarfs: toassureamuchhigherproba- Galactic contributionbybrown dwarfs,theobserveddensity sequence. TheCTImassfunctionalsoexhibitsanupturn at McCarthy (1993).Themassfunctionbasedonthe5.2pc cen- using theempiricalmass-luminosityrelationofHenry & ferences seenbetweenthetwodatasets.Moredetailedwork in more distantphotometricsampleandthesample’sinherent nantly atsouthernlatitudes(i.e.,towardtheGalacticmid- ney (1993)exceptthathisluminosityfunctionshowsnodipat real. OurdataareinroughagreementwiththeresultsofTin- sus isessentiallyflat,thenupturnstowardtheendofmain of Mdwarfscannotaccount forthepurportedmissingmass. ~M4 toM6. v v When theCTIluminosityfunctionisdividedintonorthern Luminosity functionsareconstructedat/,V,andbolomet- The CTIluminosityfunctionisalsocomparedtothatde- The CTIdataarealsousedtoconstructamassfunction Finally, weemphasizetothose searchingforfieldbrown 773 19 94ApJS. . .94. .749K request. exhibit long-termvariationstypicalofMiraorsemiregularvariables. also given.Thefightcurvesshowthemeasuredmagnitudesofthesegiants,confirmingthateachisavariablestar. Mostofthese been removed. before 1990May23haveadeadcolumnatwavelength~6410Â.AswithsimilarspectrainPapersI-IV,telluricabsorptionhasnot observation forthesespectraarelistedinTable1.TheverticalscaleisunitsofFnormalizedtooneat7500Â.Spectratakenonor CTI imagestakenthroughthe/filterondategiventorightofchart.Foreasyreference,1950coordinates(epoch~ CTI designation—acode,denotedbyhhmmss.s+ddmmss,givingtheequinox1987.5coordinatesofobject—alongwithits charts andspectraforallofthoseTable1entrieswithdwarftypesM6orlater.AtthetopeachpanelinFigure21isobject’s spectral type.Theboxenclosingeachfinderchartis4'square,withnorthatthetopandeasttoleft.Thesefindersarereduced the W.J.McDonaldFellowshipofUniversityTexasat Austin andthanksPatBoeshaar,FrankFekel,BetsyGreen, again toConardDahnforsupplyingthetabularinformation used togenerateFigure8.J.D.K.acknowledgessupportfrom ing andreducingthecalibrationphotometryofTable2, indebted toConardDahnandHughHarrisforhelpinacquir- 1990) arealsolisted.Inthelowerhalfofpanel,spectrumacquiredatMMTisshown.Theexposuretimesanddates x 774 Finder chartsforanyotherTable1entriesnotshownineitherFigure21or22canbeobtainedfromtheauthors upon In Figure22thegiantsfromTable1arepresented.isidenticalto21exceptthatfightcurveofeach objectis In thissection,fundamentaldataarepresentedforsomeofthemoreinterestingobjectslistedinTable1.Figure21presentsfinder The CTIissupportedbyNSFgrantAST88-00298.Weare SPECTRA, FINDERCHARTS,ANDLIGHTCURVESOFSELECTEDOBJECTSFROMTABLE1 © American Astronomical Society • Provided by theNASA Astrophysics Data System KIRKPATRICK ETAL. APPENDIX A database, operatedatCDS,Strasbourg,France. grant NAGW2254.ThispaperhasmadeuseoftheSIMBAD port fromNSFgrantsAST88-22465and92-03336NASA ments andsuggestions.D.W.M.J.D.K.acknowledgesup- like tothankthereferee,SandyLeggett,formanyusefulcom- and ToddHenryforenlighteningdiscussions.Wewouldalso r- OT © American Astronomical Society •Provided bythe NASAAstrophysics Data System

CTI 000455.2+280301 M6 V CTI 004244.4+280140 M6 V

Fig. 21.—Spectra and finder charts of all dwarfs in Table 1 with spectral types of M6 or later 19 94ApJS. . .94. .749K © American Astronomical Society •Provided bythe NASAAstrophysics Data System 776

Fig. 21—Continued 19 94ApJS. . .94. .749K © American Astronomical Society •Provided bythe NASAAstrophysics Data System 00 LO > CM CO LO LO CM 00 O CM O CM O I— O O I— O CD CD CNI 00 O CD + CM î> + I I ♦ 777 K) CMT-O Yxn (j) UP9ZJ|DUUJ0|S| O O O O) O O CO O oo LO LO O O I\ O O CD LO O O O _0) O Q> c: O» >

Fig. 21—Continued or OT © American Astronomical Society •Provided bythe NASAAstrophysics Data System CTI 015607.7+280241 M6.5 V CTI 015625.5+280135 M6 V 778 Yxn (j) IJP9ZI|DlJUJON

Fig. 21—Continued 03 03 © American Astronomical Society •Provided bythe NASAAstrophysics Data System

CTI 023210.0+280313 M6 V CTI 034036.8+280248 M6 V 779 xn Od) UPÔZÎIDLÜJOM m O O) O O O 00 O O O 00 O O m O o r» O O O co m O _0 0) c cr> O >

Fig. 21—Continued r" © American Astronomical Society •Provided bythe NASAAstrophysics Data System CTI 091716.8+280531 M6 Y CTI 092539.9+280018 M6.5 V 780

Fig. 21—Continued 03 03 03 03 h) a © American Astronomical Society •Provided bythe NASAAstrophysics Data System

CTI 115638.4+280000 M7 V CTI 120144.1+280527

Fig. 21—Continued 19 94ApJS. . .94. .749K © American Astronomical Society •Provided bythe NASAAstrophysics Data System 782 Yxn (j) ldpazjiDUJJON O Oí o O 03 m o o 00 ¡s ^ I O 0) O ® o o o (O LO o o -M _c c en £

Fig. 21.—Continued 19 94ApJS. . .94. .749K © American Astronomical Society •Provided bythe NASAAstrophysics Data System CD > ro CM ro ro CM CT) O O CM |\ LO + I ' ■e O -r-_ I— O) O)s= ? ° OJ o o ; m 3 I HISHH r .aá *i:,;» ■3*, 0) ' i’"*«i- 783 CNJ Q CD m o in o CM o> ro m Ö O CD CNJ QC + O 0) ^ I -+-* -C cn c

Fig. 21—Continued 19 94ApJS. . .94. .749K © American Astronomical Society •Provided bythe NASAAstrophysics Data System 784

Fig. 22—Spectra, finder charts, and light curves of those giants listed in Table 1. 19 94ApJS. . .94. .749K © American Astronomical Society •Provided bythe NASAAstrophysics Data System

Fig. 22—Continued 19 94ApJS. . .94. .749K © American Astronomical Society •Provided bythe NASAAstrophysics Data System xn Cd) UP»z!|dujjonapniiußDLU‘“a

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