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Proposal 12273 (STScI Edit Number: 0, Created: Wednesday, August 18, 2010 3:41:48 PM EDT) - Overview

12273 - Mass of the from Proper Motions of Distant Dwarf Cycle: 18, Proposal Category: GO (Availability Mode: SUPPORTED)

INVESTIGATORS Name Institution E-Mail Dr. Roeland P. van der Marel (PI) Space Telescope Science Institute [email protected] Dr. Sangmo Tony Sohn (CoI) Space Telescope Science Institute [email protected] Dr. Jay Anderson (CoI) Space Telescope Science Institute [email protected] Prof. James S. Bullock (CoI) University of California - Irvine [email protected]

VISITS Visit Targets used in Visit Configurations used in Visit Orbits Used Last Orbit Planner Run OP Current with Visit? 01 (1) -DWARF ACS/WFC 2 18-Aug-2010 15:41:34.0 yes WFC3/UVIS 02 (1) CETUS-DWARF ACS/WFC 2 18-Aug-2010 15:41:36.0 yes WFC3/UVIS 03 (2) -A-DWARF ACS/WFC 2 18-Aug-2010 15:41:38.0 yes WFC3/UVIS 04 (2) LEO-A-DWARF ACS/WFC 2 18-Aug-2010 15:41:40.0 yes WFC3/UVIS 05 (3) -DWARF ACS/WFC 2 18-Aug-2010 15:41:41.0 yes WFC3/UVIS 06 (3) TUCANA-DWARF ACS/WFC 2 18-Aug-2010 15:41:43.0 yes WFC3/UVIS 1 Proposal 12273 (STScI Edit Number: 0, Created: Wednesday, August 18, 2010 3:41:48 PM EDT) - Overview Visit Targets used in Visit Configurations used in Visit Orbits Used Last Orbit Planner Run OP Current with Visit? 07 (4) -DWARF- ACS/WFC 2 18-Aug-2010 15:41:44.0 yes IRREGULAR WFC3/UVIS 08 (4) SAGITTARIUS-DWARF- ACS/WFC 2 18-Aug-2010 15:41:46.0 yes IRREGULAR WFC3/UVIS 09 (4) SAGITTARIUS-DWARF- ACS/WFC 2 18-Aug-2010 15:41:47.0 yes IRREGULAR WFC3/UVIS 18 Total Orbits Used

ABSTRACT The Local Group and its two dominant spirals, the Milky Way and M31, have become the benchmark for testing many aspects of cosmological and formation theories, due to many exciting new discoveries in the past decade. However, it is difficult to put results in a proper cosmological context, because our knowledge of the mass M of the Local Group remains uncertain by a factor 4. In units of 10^{12} solar masses, a spherical infall model for the zero-velocity surface gives M~1.3; the sum of estimates for the Milky Way and M31 masses gives M~2.6; and the Local Group Timing argument for the M31 orbit gives M~5.6. It is possible to discriminate between the proposed masses by calculating the orbits of galaxies at the edge of the Local Group, which requires knowledge of transverse velocity components. We therefore propose to use ACS/WFC to determine the proper motions of the 4 dwarf galaxies near the edge of the Local Group (Cetus, , Tucana, Sag DIG) for which deep first epoch data (with 5-7 year time baselines) already exist in the HST Archive. Our team has extensive expertise with HST astrometric science, and our past/ongoing work for, e.g., Omega Cen, LMC/SMC and M31 show that the necessary astrometric accuracy is within the reach of HST's demonstrated capabilities. We have developed, tested, and published a new technique that uses compact background galaxies as astrometric reference sources, and we have already reduced the first epoch data. The final predicted transverse velocity accuracy, 36 km/s when averaged over the sample, will be sufficient to discriminate between each of the proposed Local Group masses at 2-sigma significance (4-sigma between the most extreme values). Our project will yield the most accurate Local Group mass determination to date, and only HST can achieve the required accuracy.

OBSERVING DESCRIPTION To measure absolute proper motions of the four target galaxies Cetus, Leo A, Tucana, and Sag DIG dwarf galaxies, we will use compact background galaxies in the field view as stationary reference sources. We will measure the average motion of in each Local Group galaxy between epochs 1 and 2 with respect to these reference sources. Our analysis techniques and expected accuracies are described in the Phase I proposal. First epoch ACS 2 Proposal 12273 (STScI Edit Number: 0, Created: Wednesday, August 18, 2010 3:41:48 PM EDT) - Overview data are available in the archive from previous observing programs. The present project will obtain the second epoch data.

The first epoch ACS data were obtained in at least two filters to make deep color magnitude diagrams for the target galaxies. The available broad- band colors and depth are sufficient for separating stars, foreground stars, and background galaxies to first order. For the second epoch it is therefore sufficient to take data in only one of the filters. For Cetus, Leo A, and Tucana dwarfs, we will use the first epoch data to build templates for background galaxies. For SAGDIG, however, our analysis shows that the first epoch data are neither deep nor well-dithered enough to build high signal-to-noise and high resolution templates for the background galaxies. We will therefore use our deeper second epoch F814W data for building the templates for SAGDIG.

We will observe each target galaxy with the F814W filter using the same pointing and orientation used for the first epoch data. Individual exposures will be sub-pixel dithered and will last half an orbit. We will use customized dither patterns designed by Jay Anderson (STScI) to maximize the pixel phase coverage. We require that all of our images be obtained in 30-60 day windows so that they can be treated as single epoch data for astrometric analyses.

During our second epoch observations, the WFC3/UVIS camera will be pointed ~6 arcmin away in the outer halo of each . We will observe those fields with F475W and F814W filters to construct color-magnitude diagrams of the outer halos. These will be used to determine stellar population gradients and the stellar halo density profile to constrain formation and evolutionary scenarios.

REAL TIME JUSTIFICATION N/A

CALIBRATION JUSTIFICATION N/A

ADDITIONAL COMMENTS N/A

3 Proposal 12273(STScIEditNumber:0,Created:Wednesday,August18,20103:41:48 PMEDT)-Overview Exposures Fixed Targets Visit 8 7 6 5 4 3 2 1 # Comments: Thisobjectwasgeneratedbythetargetselectorandretrieved fromtheSIMBADdatabase. (1) # 4-point dithering.WerequirethatVisits01and02beobservedina30day windowsothattheycanbetreatedassingleepochdataforastrometricanalysis. exactly matchthepreviousobservationsofPID10505.Weadoptacustomized ditherpatterndesignedtooptimallycoverthepixelphaseusingPOST-ARGspecialrequirements.Foreachvisitwewilldoasetof Comments: ThisisthefirstvisitforimagingCetusDwarfGalaxy.Twoorbitsarerequiredtocompletethisvisit.Sinceourgoalmeasure propermotionsofstarsinthetargetgalaxy,ourorientationissetto Special Requirements:ORIENT266.014664DTO266.014664D;GROUP01,02WITHIN30D Scientific Instruments:ACS/WFC,WFC3/UVIS Diagnostic Status:NoDiagnostics Proposal 12273,Visit01,implementation dither4 cetus-wfc3- her4 cetus-acs-dit dither3 cetus-wfc3- her3 cetus-acs-dit dither2 cetus-wfc3- her2 cetus-acs-dit dither1 cetus-wcs3- her1 cetus-acs-dit Label CETUS-DWARF Name (1) CETUS-DWARF (1) CETUS-DWARF (1) CETUS-DWARF Target (1) CETUS-DWARF (1) CETUS-DWARF (1) CETUS-DWARF (1) CETUS-DWARF (1) CETUS-DWARF : J2000 Dec: -110435.00(-11.07639d) RA: 00269.7000(6.5404167d) Target Coordinates WFC3/UVIS, ACCUM, UVIS ACS/WFC, ACCUM,WFCENTER WFC3/UVIS, ACCUM,UVIS ACS/WFC, ACCUM,WFCENTER WFC3/UVIS, ACCUM,UVIS ACS/WFC, ACCUM,WFCENTER WFC3/UVIS, ACCUM,UVIS ACS/WFC, ACCUM,WFCENTER Config,Mode,Aperture F814W F814W F814W F475W F814W Spectral Els. F814W F814W F475W Targ. Coord.Corrections CR-SPLIT=NO CR-SPLIT=NO CR-SPLIT=NO CR-SPLIT=NO CR-SPLIT=NO Opt. Params. CR-SPLIT=NO CR-SPLIT=NO CR-SPLIT=NO 4 .1235 POS TARG0.3232,0 .2350 POS TARG0.1740,0 .0000 POS TARG0.0000,0 Special Reqs. .3305 POS TARG0.1005,0 V=14.4+/-0.2 Fluxes up 7-8 Prime +ParallelGro t Sequence 5-8Non-In up 7-8 Prime +ParallelGro t Sequence 5-8Non-In up 5-6 Prime +ParallelGro t Sequence 5-8Non-In up 5-6 Prime +ParallelGro t Sequence 5-8Non-In up 3-4 Prime +ParallelGro t Sequence 1-4Non-In up 3-4 Prime +ParallelGro t Sequence 1-4Non-In up 1-2 Prime +ParallelGro t Sequence 1-4Non-In up 1-2 Prime +ParallelGro t Sequence 1-4Non-In Groups [==>] 1354 Secs [==>] 1364 Secs [==>] 1347 Secs [==>] 1363 Secs [==>] 1251 Secs [==>] 1267 Secs [==>] 1327 Secs [==>] 1267 Secs Exp. Time/[ActualDur.] Reference Frame:ICRS Miscellaneous Wed Aug1819:41:48GMT2010 Orbit [2] [2] [2] [2] [1] [1] [1] [1] Proposal 12273(STScIEditNumber:0,Created:Wednesday,August18,20103:41:48 PMEDT)-Overview Orbit Structure 5 Proposal 12273-Visit01MassoftheLocalGroupfromProperMotionsDistantDwarf Galaxies Exposures Fixed Targets Visit 8 7 6 5 4 3 2 1 # Comments: Thisobjectwasgeneratedbythetargetselectorandretrieved fromtheSIMBADdatabase. (1) # window sothattheycanbetreatedassingleepochdataforastrometricanalysis. dither patterndesignedtooptimallycoverthepixelphaseusingPOS-TARG specialrequirements.Foreachvisitwewilldoasetof4-pointdithering.WerequestthatVisits01and02beobservedin30day Comments: ThisisthesecondvisitforimagingCetusDwarfGalaxy.Twoorbitsarerequiredtocompletethisvisit.Werequestthatorientation beexactlythesameasthatofVisit01.Weadoptacustomized Special Requirements:SAMEORIENTAS01;GROUP02,01WITHIN30D Scientific Instruments:ACS/WFC,WFC3/UVIS Diagnostic Status:NoDiagnostics Proposal 12273,Visit02,implementation dither8 cetus-wfc3- her8 cetus-acs-dit dither7 cetus-wfc3- her7 cetus-acs-dit dither6 cetus-wfc3- her6 cetus-acs-dit dither5 cetus-wfc3- her5 cetus-acs-dit Label CETUS-DWARF Name (1) CETUS-DWARF (1) CETUS-DWARF (1) CETUS-DWARF Target (1) CETUS-DWARF (1) CETUS-DWARF (1) CETUS-DWARF (1) CETUS-DWARF (1) CETUS-DWARF Equinox: J2000 Dec: -110435.00(-11.07639d) RA: 00269.7000(6.5404167d) Target Coordinates WFC3/UVIS, ACCUM, UVIS ACS/WFC, ACCUM,WFCENTER WFC3/UVIS, ACCUM,UVIS ACS/WFC, ACCUM,WFCENTER WFC3/UVIS, ACCUM,UVIS ACS/WFC, ACCUM,WFCENTER WFC3/UVIS, ACCUM,UVIS ACS/WFC, ACCUM,WFCENTER Config,Mode,Aperture F814W F814W F814W F475W F814W Spectral Els. F814W F814W F475W Targ. Coord.Corrections CR-SPLIT=NO CR-SPLIT=NO CR-SPLIT=NO CR-SPLIT=NO CR-SPLIT=NO Opt. Params. CR-SPLIT=NO CR-SPLIT=NO CR-SPLIT=NO 6 .1735 POS TARG0.8300,0 .2855 POS TARG0.6815,0 .0505 POS TARG0.5075,0 Special Reqs. .3810 POS TARG0.6080,0 V=14.4+/-0.2 Fluxes up 7-8 Prime +ParallelGro t Sequence 5-8Non-In up 7-8 Prime +ParallelGro t Sequence 5-8Non-In up 5-6 Prime +ParallelGro t Sequence 5-8Non-In up 5-6 Prime +ParallelGro t Sequence 5-8Non-In up 3-4 Prime +ParallelGro t Sequence 1-4Non-In up 3-4 Prime +ParallelGro t Sequence 1-4Non-In up 1-2 Prime +ParallelGro t Sequence 1-4Non-In up 1-2 Prime +ParallelGro t Sequence 1-4Non-In Groups [==>] 1354 Secs [==>] 1364 Secs [==>] 1347 Secs [==>] 1363 Secs [==>] 1251 Secs [==>] 1267 Secs [==>] 1327 Secs [==>] 1267 Secs Exp. Time/[ActualDur.] Reference Frame:ICRS Miscellaneous Wed Aug1819:41:48GMT2010 Orbit [2] [2] [2] [2] [1] [1] [1] [1] Proposal 12273-Visit01MassoftheLocalGroupfromProperMotionsDistantDwarf Galaxies Orbit Structure 7 Proposal 12273-Visit02MassoftheLocalGroupfromProperMotionsDistantDwarf Galaxies Exposures Fixed Targets Visit 8 7 6 5 4 3 2 1 # Comments: Thisobjectwasgeneratedbythetargetselectorandretrieved fromtheNEDdatabase. (2) # 4-point dithering.WerequestthatVisits03and04beobservedina30day windowsothattheycanbetreatedassingleepochdataforastrometricanalysis. exactly matchthepreviousobservationsofPID10590.Weadoptacustomized ditherpatterndesignedtooptimallycoverthepixelphaseusingPOS-TARGspecialrequirements.Foreachvisitwewilldoasetof Comments: ThisisthefirstvisitforimagingLeoADwarfGalaxy.Twoorbitsarerequiredtocompletethisvisit.Sinceourgoalmeasure propermotionsofstarsinthetargetgalaxy,ourorientationissetto Special Requirements:ORIENT282.484802DTO287.5D;GROUP03,04WITHIN30D Scientific Instruments:ACS/WFC,WFC3/UVIS Diagnostic Status:NoDiagnostics Proposal 12273,Visit03,implementation ther4 leoa-wfc3-di er4 leoa-acs-dith ther3 leoa-wfc3-di er3 leoa-acs-dith ther2 leoa-wfc3-di er2 leoa-acs-dith ther1 leoa-wfc3-di er1 leoa-acs-dith Label LEO-A-DWARF Name (2) LEO-A-DWARF (2) LEO-A-DWARF (2) LEO-A-DWARF Target (2) LEO-A-DWARF (2) LEO-A-DWARF (2) LEO-A-DWARF (2) LEO-A-DWARF (2) LEO-A-DWARF Equinox: J2000 Dec: +304523.80(30.75661d) RA: 095923.8000(149.8491667d) Target Coordinates WFC3/UVIS, ACCUM, UVIS ACS/WFC, ACCUM,WFC-FIX WFC3/UVIS, ACCUM,UVIS ACS/WFC, ACCUM,WFC-FIX WFC3/UVIS, ACCUM,UVIS ACS/WFC, ACCUM,WFC-FIX WFC3/UVIS, ACCUM,UVIS ACS/WFC, ACCUM,WFC-FIX Config,Mode,Aperture F814W F814W F814W F475W F814W Spectral Els. F814W F814W F475W Targ. Coord.Corrections CR-SPLIT=NO CR-SPLIT=NO CR-SPLIT=NO CR-SPLIT=NO CR-SPLIT=NO Opt. Params. CR-SPLIT=NO CR-SPLIT=NO CR-SPLIT=NO 8 .1235 POS TARG0.3232,0 .2350 POS TARG0.1740,0 .0000 POS TARG0.0000,0 Special Reqs. .3305 POS TARG0.1005,0 V=12.5+/-0.2 Fluxes up 7-8 Prime +ParallelGro t Sequence 5-8Non-In up 7-8 Prime +ParallelGro t Sequence 5-8Non-In up 5-6 Prime +ParallelGro t Sequence 5-8Non-In up 5-6 Prime +ParallelGro t Sequence 5-8Non-In up 3-4 Prime +ParallelGro t Sequence 1-4Non-In up 3-4 Prime +ParallelGro t Sequence 1-4Non-In up 1-2 Prime +ParallelGro t Sequence 1-4Non-In up 1-2 Prime +ParallelGro t Sequence 1-4Non-In Groups [==>] 1369 Secs [==>] 1379 Secs [==>] 1362 Secs [==>] 1378 Secs [==>] 1272 Secs [==>] 1282 Secs [==>] 1342 Secs [==>] 1282 Secs Exp. Time/[ActualDur.] Reference Frame:ICRS Miscellaneous Wed Aug1819:41:49GMT2010 Orbit [2] [2] [2] [2] [1] [1] [1] [1] Proposal 12273-Visit02MassoftheLocalGroupfromProperMotionsDistantDwarf Galaxies Orbit Structure 9 Proposal 12273-Visit03MassoftheLocalGroupfromProperMotionsDistantDwarf Galaxies Exposures Fixed Targets Visit 8 7 6 5 4 3 2 1 # Comments: Thisobjectwasgeneratedbythetargetselectorandretrieved fromtheNEDdatabase. (2) # window sothattheycanbetreatedassingleepochdataforastrometricanalysis. dither patterndesignedtooptimallycoverthepixelphaseusingPOS-TARG specialrequirements.Foreachvisitwewilldoasetof4-pointdithering.WerequestthatVisits03and04beobservedin30day Comments: ThisisthesecondvisitforimagingLeoADwarfGalaxy.Twoorbitsarerequiredtocompletethisvisit.Werequestthatorientation beexactlythesameasthatofVisit03.Weadoptacustomized Special Requirements:SAMEORIENTAS03;GROUP04,03WITHIN30D Scientific Instruments:ACS/WFC,WFC3/UVIS Diagnostic Status:NoDiagnostics Proposal 12273,Visit04,implementation ther8 leoa-wfc3-di er8 leoa-acs-dith ther7 leoa-wfc3-di er7 leoa-acs-dith ther6 leoa-wfc3-di er6 leoa-acs-dith ther5 leoa-wfc3-di er5 leoa-acs-dith Label LEO-A-DWARF Name (2) LEO-A-DWARF (2) LEO-A-DWARF (2) LEO-A-DWARF Target (2) LEO-A-DWARF (2) LEO-A-DWARF (2) LEO-A-DWARF (2) LEO-A-DWARF (2) LEO-A-DWARF Equinox: J2000 Dec: +304523.80(30.75661d) RA: 095923.8000(149.8491667d) Target Coordinates WFC3/UVIS, ACCUM, UVIS ACS/WFC, ACCUM,WFC-FIX WFC3/UVIS, ACCUM,UVIS ACS/WFC, ACCUM,WFC-FIX WFC3/UVIS, ACCUM,UVIS ACS/WFC, ACCUM,WFC-FIX WFC3/UVIS, ACCUM,UVIS ACS/WFC, ACCUM,WFC-FIX Config,Mode,Aperture F814W F814W F814W F475W F814W Spectral Els. F814W F814W F475W Targ. Coord.Corrections CR-SPLIT=NO CR-SPLIT=NO CR-SPLIT=NO CR-SPLIT=NO CR-SPLIT=NO Opt. Params. CR-SPLIT=NO CR-SPLIT=NO CR-SPLIT=NO 10 .1735 POS TARG0.8300,0 .2855 POS TARG0.6815,0 .0505 POS TARG0.5075,0 Special Reqs. .3810 POS TARG0.6080,0 V=12.5+/-0.2 Fluxes up 7-8 Prime +ParallelGro t Sequence 5-8Non-In up 7-8 Prime +ParallelGro t Sequence 5-8Non-In up 5-6 Prime +ParallelGro t Sequence 5-8Non-In up 5-6 Prime +ParallelGro t Sequence 5-8Non-In up 3-4 Prime +ParallelGro t Sequence 1-4Non-In up 3-4 Prime +ParallelGro t Sequence 1-4Non-In up 1-2 Prime +ParallelGro t Sequence 1-4Non-In up 1-2 Prime +ParallelGro t Sequence 1-4Non-In Groups [==>] 1369 Secs [==>] 1379 Secs [==>] 1362 Secs [==>] 1378 Secs [==>] 1272 Secs [==>] 1282 Secs [==>] 1342 Secs [==>] 1282 Secs Exp. Time/[ActualDur.] Reference Frame:ICRS Miscellaneous Wed Aug1819:41:49GMT2010 Orbit [2] [2] [2] [2] [1] [1] [1] [1] Proposal 12273-Visit03MassoftheLocalGroupfromProperMotionsDistantDwarf Galaxies Orbit Structure 11 Proposal 12273-Visit04MassoftheLocalGroupfromProperMotionsDistantDwarf Galaxies Exposures Fixed Targets Visit 8 7 6 5 4 3 2 1 # Comments: Thisobjectwasgeneratedbythetargetselectorandretrieved fromtheNEDdatabase. (3) # 4-point dithering.WerequestthatVisits05and06beobservedina30day windowsothattheycanbetreatedassingleepochdataforastrometricanalysis. exactly matchthepreviousobservationsofPID10505.Weadoptacustomized ditherpatterndesignedtooptimallycoverthepixelphaseusingPOS-TARGspecialrequirements.Foreachvisitwewilldoasetof Comments: ThisisthefirstvisitforimagingTucanaDwarfGalaxy.Twoorbitsarerequiredtocompletethisvisit.Sinceourgoalmeasure propermotionsofstarsinthetargetgalaxy,ourorientationissetto Special Requirements:ORIENT231.55373DTO231.55373D;GROUP05,06WITHIN30D Scientific Instruments:ACS/WFC,WFC3/UVIS Diagnostic Status:NoDiagnostics Proposal 12273,Visit05,implementation -dither4 tucana-wfc3 ither4 tucana-acs-d -dither3 tucana-wfc3 ither3 tucana-acs-d -dither2 tucana-wfc3 ither2 tucana-acs-d -dither1 tucana-wfc3 ither1 tucana-acs-d Label TUCANA-DWARF Name RF (3) TUCANA-DWA RF (3) TUCANA-DWA RF (3) TUCANA-DWA Target RF (3) TUCANA-DWA RF (3) TUCANA-DWA RF (3) TUCANA-DWA RF (3) TUCANA-DWA RF (3) TUCANA-DWA Equinox: J2000 Dec: -642516.05(-64.42113d) RA: 224148.4200(340.4517500d) Target Coordinates WFC3/UVIS, ACCUM, UVIS ACS/WFC, ACCUM,WFCENTER WFC3/UVIS, ACCUM,UVIS ACS/WFC, ACCUM,WFCENTER WFC3/UVIS, ACCUM,UVIS ACS/WFC, ACCUM,WFCENTER WFC3/UVIS, ACCUM,UVIS ACS/WFC, ACCUM,WFCENTER Config,Mode,Aperture F814W F814W F814W F475W F814W Spectral Els. F814W F814W F475W Targ. Coord.Corrections CR-SPLIT=NO CR-SPLIT=NO CR-SPLIT=NO CR-SPLIT=NO CR-SPLIT=NO Opt. Params. CR-SPLIT=NO CR-SPLIT=NO CR-SPLIT=NO 12 .1235 POS TARG0.3232,0 .2350 POS TARG0.1740,0 .0000 POS TARG0.0000,0 Special Reqs. .3305 POS TARG0.1005,0 V=15.2+/-0.2 Fluxes up 7-8 Prime +ParallelGro t Sequence 5-8Non-In up 7-8 Prime +ParallelGro t Sequence 5-8Non-In up 5-6 Prime +ParallelGro t Sequence 5-8Non-In up 5-6 Prime +ParallelGro t Sequence 5-8Non-In up 3-4 Prime +ParallelGro t Sequence 1-4Non-In up 3-4 Prime +ParallelGro t Sequence 1-4Non-In up 1-2 Prime +ParallelGro t Sequence 1-4Non-In up 1-2 Prime +ParallelGro t Sequence 1-4Non-In Groups [==>] 1489 Secs [==>] 1499 Secs [==>] 1483 Secs [==>] 1499 Secs [==>] 1393 Secs [==>] 1403 Secs [==>] 1462 Secs [==>] 1402 Secs Exp. Time/[ActualDur.] Reference Frame:ICRS Miscellaneous Wed Aug1819:41:49GMT2010 Orbit [2] [2] [2] [2] [1] [1] [1] [1] Proposal 12273-Visit04MassoftheLocalGroupfromProperMotionsDistantDwarf Galaxies Orbit Structure 13 Proposal 12273-Visit05MassoftheLocalGroupfromProperMotionsDistantDwarf Galaxies Exposures Fixed Targets Visit 8 7 6 5 4 3 2 1 # Comments: Thisobjectwasgeneratedbythetargetselectorandretrieved fromtheNEDdatabase. (3) # that theycanbetreatedassingleepochdataforastrometricanalysis. pattern designedtooptimallycoverthepixelphaseusingPOS-TARG specialrequirements.Foreachvisitwewilldoasetof4-pointdithering.WerequestthatVisits05and06beobservedin30daywindowso Comments: ThisisthesecondvisitforimagingTucanaDwarfGalaxy.Twoorbitsarerequiredtocompletethisvisit.Werequestthatorientation beexactlythesameasVisit05.Weadoptacustomizeddither Special Requirements:SAMEORIENTAS05;GROUP06,05WITHIN30D Scientific Instruments:ACS/WFC,WFC3/UVIS Diagnostic Status:NoDiagnostics Proposal 12273,Visit06,implementation -dither8 tucana-wfc3 ither8 tucana-acs-d -dither7 tucana-wfc3 ither7 tucana-acs-d -dither6 tucana-wfc3 ither6 tucana-acs-d -dither5 tucana-wfc3 ither5 tucana-acs-d Label TUCANA-DWARF Name RF (3) TUCANA-DWA RF (3) TUCANA-DWA RF (3) TUCANA-DWA Target RF (3) TUCANA-DWA RF (3) TUCANA-DWA RF (3) TUCANA-DWA RF (3) TUCANA-DWA RF (3) TUCANA-DWA Equinox: J2000 Dec: -642516.05(-64.42113d) RA: 224148.4200(340.4517500d) Target Coordinates WFC3/UVIS, ACCUM, UVIS ACS/WFC, ACCUM,WFCENTER WFC3/UVIS, ACCUM,UVIS ACS/WFC, ACCUM,WFCENTER WFC3/UVIS, ACCUM,UVIS ACS/WFC, ACCUM,WFCENTER WFC3/UVIS, ACCUM,UVIS ACS/WFC, ACCUM,WFCENTER Config,Mode,Aperture F814W F814W F814W F475W F814W Spectral Els. F814W F814W F475W Targ. Coord.Corrections CR-SPLIT=NO CR-SPLIT=NO CR-SPLIT=NO CR-SPLIT=NO CR-SPLIT=NO Opt. Params. CR-SPLIT=NO CR-SPLIT=NO CR-SPLIT=NO 14 .1735 POS TARG0.8300,0 .2855 POS TARG0.6815,0 .0505 POS TARG0.5075,0 Special Reqs. .3810 POS TARG0.6080,0 V=15.2+/-0.2 Fluxes up 7-8 Prime +ParallelGro t Sequence 5-8Non-In up 7-8 Prime +ParallelGro t Sequence 5-8Non-In up 5-6 Prime +ParallelGro t Sequence 5-8Non-In up 5-6 Prime +ParallelGro t Sequence 5-8Non-In up 3-4 Prime +ParallelGro t Sequence 1-4Non-In up 3-4 Prime +ParallelGro t Sequence 1-4Non-In up 1-2 Prime +ParallelGro t Sequence 1-4Non-In up 1-2 Prime +ParallelGro t Sequence 1-4Non-In Groups [==>] 1489 Secs [==>] 1499 Secs [==>] 1483 Secs [==>] 1499 Secs [==>] 1393 Secs [==>] 1403 Secs [==>] 1462 Secs [==>] 1402 Secs Exp. Time/[ActualDur.] Reference Frame:ICRS Miscellaneous Wed Aug1819:41:49GMT2010 Orbit [2] [2] [2] [2] [1] [1] [1] [1] Proposal 12273-Visit05MassoftheLocalGroupfromProperMotionsDistantDwarf Galaxies Orbit Structure 15 Proposal 12273-Visit06MassoftheLocalGroupfromProperMotionsDistantDwarf Galaxies Exposures Fixed Targets Visit 8 7 6 5 4 3 2 1 # Comments: Thisobjectwasgeneratedbythetargetselectorandretrieved fromtheNEDdatabase. (4) # visit wewilldoasetof4-pointdithering.WerequestthatVisits07,08,and 09beobservedina60daywindowsothattheycantreatedassingleepochdataforastrometricanalysis. our orientationissettoexactlymatchthepreviousobservationsofPID9820. WeadoptacustomizedditherpatterndesignedtooptimallycoverthepixelphaseusingPOS-TARGspecialrequirements.Foreach Comments: ThisisthefirstvisitforimagingSagittariusDwarfIrregularGalaxy(SAGDIG).Twoorbitsarerequiredtocompletethisvisit.Since ourgoalistomeasurepropermotionsofstarsinthetargetgalaxy, Special Requirements:ORIENT87.260712DTO87.260712D;GROUP07,08,09WITHIN60D Scientific Instruments:ACS/WFC,WFC3/UVIS Diagnostic Status:NoDiagnostics Proposal 12273,Visit07,implementation -dither4 sagdig-wfc3 ither4 sagdig-acs-d -dither3 sagdig-wfc3 ither3 sagdig-acs-d -dither2 sagdig-wfc3 ither2 sagdig-acs-d -dither1 sagdig-wfc3 ither1 sagdig-acs-d Label DWARF-IRREGULAR SAGITTARIUS- Name AR DWARF-IRREGUL (4) SAGITTARIUS- AR DWARF-IRREGUL (4) SAGITTARIUS- AR DWARF-IRREGUL (4) SAGITTARIUS- Target AR DWARF-IRREGUL (4) SAGITTARIUS- AR DWARF-IRREGUL (4) SAGITTARIUS- AR DWARF-IRREGUL (4) SAGITTARIUS- AR DWARF-IRREGUL (4) SAGITTARIUS- AR DWARF-IRREGUL (4) SAGITTARIUS- Equinox: J2000 Dec: -174046.42(-17.67956d) RA: 19300.0700(292.5002917d) Target Coordinates WFC3/UVIS, ACCUM, UVIS ACS/WFC, ACCUM,WFC-FIX WFC3/UVIS, ACCUM,UVIS ACS/WFC, ACCUM,WFC-FIX WFC3/UVIS, ACCUM,UVIS ACS/WFC, ACCUM,WFC-FIX WFC3/UVIS, ACCUM,UVIS ACS/WFC, ACCUM,WFC-FIX Config,Mode,Aperture F814W F814W F814W F475W F814W Spectral Els. F814W F814W F475W Targ. Coord.Corrections CR-SPLIT=NO CR-SPLIT=NO CR-SPLIT=NO CR-SPLIT=NO CR-SPLIT=NO Opt. Params. CR-SPLIT=NO CR-SPLIT=NO CR-SPLIT=NO 16 .1235 POS TARG0.3232,0 .1850 POS TARG0.1740,0 .0000 POS TARG0.0000,0 Special Reqs. .3305 POS TARG0.1005,0 V=14.3+/-0.2 Fluxes up 7-8 Prime +ParallelGro t Sequence 5-8Non-In up 7-8 Prime +ParallelGro t Sequence 5-8Non-In up 5-6 Prime +ParallelGro t Sequence 5-8Non-In up 5-6 Prime +ParallelGro t Sequence 5-8Non-In up 3-4 Prime +ParallelGro t Sequence 1-4Non-In up 3-4 Prime +ParallelGro t Sequence 1-4Non-In up 1-2 Prime +ParallelGro t Sequence 1-4Non-In up 1-2 Prime +ParallelGro t Sequence 1-4Non-In Groups [==>] 1356 Secs [==>] 1366 Secs [==>] 1349 Secs [==>] 1365 Secs [==>] 1259 Secs [==>] 1269 Secs [==>] 1329 Secs [==>] 1269 Secs Exp. Time/[ActualDur.] Reference Frame:ICRS Miscellaneous Wed Aug1819:41:49GMT2010 Orbit [2] [2] [2] [2] [1] [1] [1] [1] Proposal 12273-Visit06MassoftheLocalGroupfromProperMotionsDistantDwarf Galaxies Orbit Structure 17 Proposal 12273-Visit07MassoftheLocalGroupfromProperMotionsDistantDwarf Galaxies Exposures Fixed Targets Visit 8 7 6 5 4 3 2 1 # Comments: Thisobjectwasgeneratedbythetargetselectorandretrieved fromtheNEDdatabase. (4) # be observedina60daywindowsothattheycantreatedassingleepoch dataforastrometricanalysis. We adoptacustomizedditherpatterndesignedtooptimallycoverthepixel phaseusingthePOS-TARGspecialrequirements.Foreachvisitwewilldoasetof4-pointdithering.WerequestthatVisits07,08,and09 Comments: ThisisthesecondvisitforimagingSagittariusDwarfIrregularGalaxy(SAGDIG).Twoorbitsarerequiredtocompletethisvisit. WerequestthattheorientationbeexactlysameasofVisit07. Special Requirements:SAMEORIENTAS07;GROUP08,07,09WITHIN60D Scientific Instruments:ACS/WFC,WFC3/UVIS Diagnostic Status:NoDiagnostics Proposal 12273,Visit08,implementation -dither8 sagdig-wfc3 ither8 sagdig-acs-d -dither7 sagdig-wfc3 ither7 sagdig-acs-d -dither6 sagdig-wfc3 ither6 sagdig-acs-d -dither5 sagdig-wfc3 ither5 sagdig-acs-d Label DWARF-IRREGULAR SAGITTARIUS- Name AR DWARF-IRREGUL (4) SAGITTARIUS- AR DWARF-IRREGUL (4) SAGITTARIUS- AR DWARF-IRREGUL (4) SAGITTARIUS- Target AR DWARF-IRREGUL (4) SAGITTARIUS- AR DWARF-IRREGUL (4) SAGITTARIUS- AR DWARF-IRREGUL (4) SAGITTARIUS- AR DWARF-IRREGUL (4) SAGITTARIUS- AR DWARF-IRREGUL (4) SAGITTARIUS- Equinox: J2000 Dec: -174046.42(-17.67956d) RA: 19300.0700(292.5002917d) Target Coordinates WFC3/UVIS, ACCUM, UVIS ACS/WFC, ACCUM,WFC-FIX WFC3/UVIS, ACCUM,UVIS ACS/WFC, ACCUM,WFC-FIX WFC3/UVIS, ACCUM,UVIS ACS/WFC, ACCUM,WFC-FIX WFC3/UVIS, ACCUM,UVIS ACS/WFC, ACCUM,WFC-FIX Config,Mode,Aperture F814W F814W F814W F475W F814W Spectral Els. F814W F814W F475W Targ. Coord.Corrections CR-SPLIT=NO CR-SPLIT=NO CR-SPLIT=NO CR-SPLIT=NO CR-SPLIT=NO Opt. Params. CR-SPLIT=NO CR-SPLIT=NO CR-SPLIT=NO 18 .1695 POS TARG0.8262,0 .2310 POS TARG0.6770,0 .0460 POS TARG0.5030,0 Special Reqs. .3765 POS TARG0.6035,0 V=14.3+/-0.2 Fluxes up 7-8 Prime +ParallelGro t Sequence 5-8Non-In up 7-8 Prime +ParallelGro t Sequence 5-8Non-In up 5-6 Prime +ParallelGro t Sequence 5-8Non-In up 5-6 Prime +ParallelGro t Sequence 5-8Non-In up 3-4 Prime +ParallelGro t Sequence 1-4Non-In up 3-4 Prime +ParallelGro t Sequence 1-4Non-In up 1-2 Prime +ParallelGro t Sequence 1-4Non-In up 1-2 Prime +ParallelGro t Sequence 1-4Non-In Groups [==>] 1356 Secs [==>] 1366 Secs [==>] 1349 Secs [==>] 1365 Secs [==>] 1259 Secs [==>] 1269 Secs [==>] 1329 Secs [==>] 1269 Secs Exp. Time/[ActualDur.] Reference Frame:ICRS Miscellaneous Wed Aug1819:41:49GMT2010 Orbit [2] [2] [2] [2] [1] [1] [1] [1] Proposal 12273-Visit07MassoftheLocalGroupfromProperMotionsDistantDwarf Galaxies Orbit Structure 19 Proposal 12273-Visit08MassoftheLocalGroupfromProperMotionsDistantDwarf Galaxies Exposures Fixed Targets Visit 8 7 6 5 4 3 2 1 # Comments: Thisobjectwasgeneratedbythetargetselectorandretrieved fromtheNEDdatabase. (4) # be observedina60daywindowsothattheycantreatedassingleepoch dataforastrometricanalysis. We adoptacustomizedditherpatterndesignedtooptimallycoverthepixel phaseusingthePOS-TARGspecialrequirements.Foreachvisitwewilldoasetof4-pointdithering.WerequestthatVisits07,08,and09 Comments: ThisisthethirdvisitforimagingSagittariusDwarfIrregularGalaxy(SAGDIG).Twoorbitsarerequiredtocompletethisvisit. We requestthattheorientationbeexactlysameasofVisit07. Special Requirements:SAMEORIENTAS07;GROUP09,07,08WITHIN60D Scientific Instruments:ACS/WFC,WFC3/UVIS Diagnostic Status:NoDiagnostics Proposal 12273,Visit09,implementation -dither12 sagdig-wfc3 ither12 sagdig-acs-d -dither11 sagdig-wfc3 ither11 sagdig-acs-d -dither10 sagdig-wfc3 ither10 sagdig-acs-d -dither9 sagdig-wfc3 ither9 sagdig-acs-d Label DWARF-IRREGULAR SAGITTARIUS- Name AR DWARF-IRREGUL (4) SAGITTARIUS- AR DWARF-IRREGUL (4) SAGITTARIUS- AR DWARF-IRREGUL (4) SAGITTARIUS- Target AR DWARF-IRREGUL (4) SAGITTARIUS- AR DWARF-IRREGUL (4) SAGITTARIUS- AR DWARF-IRREGUL (4) SAGITTARIUS- AR DWARF-IRREGUL (4) SAGITTARIUS- AR DWARF-IRREGUL (4) SAGITTARIUS- Equinox: J2000 Dec: -174046.42(-17.67956d) RA: 19300.0700(292.5002917d) Target Coordinates WFC3/UVIS, ACCUM, UVIS ACS/WFC, ACCUM,WFC-FIX WFC3/UVIS, ACCUM,UVIS ACS/WFC, ACCUM,WFC-FIX WFC3/UVIS, ACCUM,UVIS ACS/WFC, ACCUM,WFC-FIX WFC3/UVIS, ACCUM,UVIS ACS/WFC, ACCUM,WFC-FIX Config,Mode,Aperture F814W F814W F814W F475W F814W Spectral Els. F814W F814W F475W Targ. Coord.Corrections CR-SPLIT=NO CR-SPLIT=NO CR-SPLIT=NO CR-SPLIT=NO CR-SPLIT=NO Opt. Params. CR-SPLIT=NO CR-SPLIT=NO CR-SPLIT=NO 20 .6415 POS TARG0.4412,0 .7030 POS TARG0.2920,0 .5180 POS TARG0.1180,0 Special Reqs. .8485 POS TARG0.2185,0 V=14.3+/-0.2 Fluxes up 7-8 Prime +ParallelGro t Sequence 5-8Non-In up 7-8 Prime +ParallelGro t Sequence 5-8Non-In up 5-6 Prime +ParallelGro t Sequence 5-8Non-In up 5-6 Prime +ParallelGro t Sequence 5-8Non-In up 3-4 Prime +ParallelGro t Sequence 1-4Non-In up 3-4 Prime +ParallelGro t Sequence 1-4Non-In up 1-2 Prime +ParallelGro t Sequence 1-4Non-In up 1-2 Prime +ParallelGro t Sequence 1-4Non-In Groups [==>] 1356 Secs [==>] 1366 Secs [==>] 1349 Secs [==>] 1365 Secs [==>] 1259 Secs [==>] 1269 Secs [==>] 1329 Secs [==>] 1269 Secs Exp. Time/[ActualDur.] Reference Frame:ICRS Miscellaneous Wed Aug1819:41:49GMT2010 Orbit [2] [2] [2] [2] [1] [1] [1] [1] Proposal 12273-Visit08MassoftheLocalGroupfromProperMotionsDistantDwarf Galaxies Orbit Structure 21