View metadata, citation and similar papers at core.ac.uk brought to you by CORE

provided by Chapman University Digital Commons

Chapman University Chapman University Digital Commons Mathematics, Physics, and Computer Science Science and Technology Faculty Articles and Faculty Articles and Research Research

1982 International Ultraviolet Explorer Observations of the Aquarii Jet A. G. Michalitsianos NASA, Goddard Space Flight Center

Menas Kafatos Chapman University, [email protected]

Follow this and additional works at: http://digitalcommons.chapman.edu/scs_articles Part of the Instrumentation Commons, and the Stars, Interstellar Medium and the Galaxy Commons

Recommended Citation Michalitsianos, A.G., Kafatos, M. (1982) International Ultraviolet Explorer Observations of the Aquarii Jet, Astrophysical Journal, 262:L47-L51. doi: 10.1086/183909

This Article is brought to you for free and open access by the Science and Technology Faculty Articles and Research at Chapman University Digital Commons. It has been accepted for inclusion in Mathematics, Physics, and Computer Science Faculty Articles and Research by an authorized administrator of Chapman University Digital Commons. For more information, please contact [email protected]. International Ultraviolet Explorer Observations of the Aquarii Jet

Comments This article was originally published in Astrophysical Journal, volume 262, in 1982. DOI: 10.1086/183909

Copyright IOP Publishing

This article is available at Chapman University Digital Commons: http://digitalcommons.chapman.edu/scs_articles/130 1982ApJ...262L..47M NASA feature moderate tained [0 Greenstein and jet :.\.1892A © DIE Additionally, with been (IUE). (about tially tween UV sion. cools This the virtually the and that C 1982. The 1 Observations III], © On II], is ASTROPHYSICAL continuum wavelength 1977. symbiotic C material is obtained decreasing The American through comparatively Goddard independent leave and the with INTERNATIONAL [0 is jet 6 further II A jet and with wavelength feature, exhibited covered American Subject that the A absent ion also :.\.1335 Herbig III], ( central C Ultraviolet or comparison is at 1980), resolution) the central Si engulfs II this excitation that Space free-free characterized present the with Laboratory indicated and "spike," variable flux, also II Astronomical of headings: Very distribution wavelength the in emission optical-radio interpretation JOURNAL, :.\.1817, (1980) first by is prominent ionized Astronomical the I. with the Flight He the suggest region lower result F/1., range ejected the INTRODUCTION ionized Large at appeared recently spectra and International reveals I. in Laboratory jet. between of wavelength by R so-called central reported, 6 for Center. evident Society. stars: Subsequent in 262:L47-L51, of than the em nebula and nebular are by low-dispersion enhanced the Aquarii The in Astronomy ULTRA from Array grain of nebulosity the jet emission Department jet and were strong All important virtually discovered the general is is circumstellar that sometime UV continuum 1200-2000 in carbon rights feature feature. for that the considerably the from and by formation 1.3 recombination jet (VLA) the Ultraviolet in Society object. obtained of Astronomy (M7e VIOLET overall continuum reserved. S symbiotic observations consists em Wallerstein and 1982 feature Received jet excitation the the central II lines optical in absent of in lines differences between :.\.:.\.1250, We jet (Sopka +pee) Physics, feature. Solar the indicate November central UV central the A Printed energy excitation shells- in feature of with A. speculate that and 1982 of is • of central EXPLORER Explorer star, spectra, symbiotic in different material spectra Physics, system which Si essen­ G. Provided in of [S C George emis­ et Solar 1970 the have 1295 June rises star. star. M. U.S.A. and The the ob­ ABSTRACT the be­ are II], the III] a/. MICHALITSIANOS 15 IV, in in stars: star. jet. Physics, KAFATOS of 21; rises International AND L47 Mason that in the variable accepted This Prominent long-period appearance with OBSERVATIONS variable km between pendicular (1980) extended observations object. objects logically, gested Lick nebula light has were positioned star. superposed (1978). entrance from eliminate 1982). and eta/. UV angle jet by NASA . University, IUE could 1 that s- been the decreasing 1982 star small In Observatory R from (1982) obtained of the 1 Goddard The ) indicate Abell this Aquarii. The Figure (Herbig Kafatos instrumentation suggests Ultraviolet discrete NASA Astrophysics that August a elc the reflect apertures. (position Si ejected the the 2' most variables- central (3" to hot to Fairfax, from the relationship III] nebulosity is the on spatial feature (IUE 30 was spacecraft obtain the Space hole) 4 1, possibly wavelength subdwarf at of and central 1981 material (Hazard it and blobs The position by and the the 2' near 3 Virginia the an is star. (b)] II. Explorer At FES OF the Si m extent depletion nebulosity Flight possibly an apertures cooler VLA November far- Jones relatively aperture-centered contribution Michalitsianos OBSERVATIONS slit of ultraviolet: II direct is maximum UV central was estimate THE between the on At is UV emission monitor ejecta et not and is Center of position 6 in of described than a/. 1981) source. ejected 1982 em observed position resembles of result continuum plates the clear the R the of the for 1981 that star. reported flat the map AQUARII 5 of the silicon the = 1200-2000 IUE May light 387 lines is Data spectra and 10" (a), comparison at from instrument-scattered ). of encircles obtained continuum Finally, Consistent newly 6.5 along nebulosity shown, obtained jet present. (1982) (c), by in day low-velocity feature in tidal spectra large 7 during seen mag). in distance in of the and both System enabled Boggess the an Herbig-Haro dis­ the period the the on JET central in interaction the the A by have and the However, planetary by axis Morpho­ the our and of with which slit Herbig central central Sopka the outer, ~ us small Mira eta/. large IUE (100 sug­ per­ roll­ was UV 10" the jet to is 1982ApJ...262L..47M L48 from aperture level instrument-scattered intensity we jet star is of C /(C by from tween SWP LWR rected SWP SWP SWP spectra. LWR IUECamera FIG. Notable asee b(a): Si Image III] © estimate instrument-scattered (Table IV)//(C the 16918 16917 16916 16919 III] 13189 13188 and of that American spectra around Figure 1.-IUE R .\1909 ITF of jet No. .\1892 silicon Aqr ratio IUE ...... feature. found 1 ...... the differences of Cassatella ). III]) ...... Jet; I. of and were 2%. IUE entrance of and scattered emission !UE (b): Figure Entrance 2:: the in these Additionally, 10 10 (arcsec) 10 10 10 Astronomical Si 1, spectra 3 detected central OBSERVING axis either light hole X X X X X and II aperture 2 TABLE 20 20 20 20 20 emission in light. .\1817 light defined Slit include eta/. in is from star; emission-line were the not the contribution at We shown u c Ci 0 ~ ::::; z z w ~ PROGRAM emission 1 (c): (1980) by jet the C satisfactorily slit lines the Positiona, jet reduced suspect, the UV IV or central on (b) (b) (b) (a) (a) (c) 23h apparent Society is position .\.\1548, protruding scattered MICHALITSIANOS adopted appears central the due in 41 b structure with by VLA the therefore, m UV 15~2 entirely the explained light. jet. weakness 1550 (c). star, jet reversed for 6 • the (minutes) Exposure source, central em 14~8 If feature Provided 240 60 40 30 20 IUE 30 The cor­ and i.e., be­ the map we RIGHT to and obtained ASCENSION 14~4 AND central (c) both, countetjet are decreasing length by ergs extrapolated length data three tend find ter rises underestimates seems (1980), found and We the range been by The Assuming by that (IPC) Helfand possibly jet KAFATOS the note cm- star Greenstein indicate F>.. to very orders observed from Sopka of more in 14~0 (1950.0) range. range. below UV i.e., a: differs the are values NASA Astrophysics 2 the on possibly that .\ III. rapidly s- wavelength either shown et appropriate -n E of continuum X-ray encountering central negligible (private 1 R UV the at. The 8 DISCUSSION ~ A A - in magnitude similar _v where suggested in the Aquarii 13~6 (1982). 1980) 1300 by Einstein thermal flatter the 1 flux below = forming? jet the energy level with nebulosity dashed 0.0-0.5, communication) jet n continuum, A. Herbig-Haro The UV extinction for would over for is = in of the 13 by spectrum 1400 or If excitation AND nebular above not Observatory lines. 2.5 range long 5 the the the continuum 2 the Wallerstein we central Image the and + a jet, (Kaler CONCLUSIONS suggest A. axis Position feature, observed jet soft adopt 0.5 the (1-4 in 1200-2000 Data A however, emission is will of Proportional (with rises or in X-ray star threshold objects the within value ·1981; the keY), (HEAO-B). an (a) of composition, be X-ray properties the and the jet large System material. continuum steadily is say E ~ used source. E short-wave­ the centered 8 Wallerstein feature, at cannot Greenstein by continuum 3 where 8 _ 10" A _ obtained Vol. emission v position n X extreme v Brugel, herein. = = Coun­ wave­ X 10- = have with Is 0.65 262 1.5) 20" His 10" ex­ the 0.0 we or in 13 a 1982ApJ...262L..47M No.2, plicable shown the which previously by (1980). ate at emission for for continuum of Bohm, tures that the weaker stellar sion-line out found compared tinua tion A ~ N(C assume feature that Fro. 0.1 The © 2000 1900 is top nebular for the observed Herbig-Haro emission the II)+ the of in American from are of only spectrum 1982 decreased here 2.-Short-wavelength ultraviolet and absolute than T. is central The A. computed Michalitsianos the here. that A the not fluxes measure, UV negligible = N(C with continuum However, is~ hot below Mannery ~ jet by a observed the corrected 10 only UV could the 2.5 factor for line region are 4 stars are III)+ central Michalitsianos, emission-line 10- the Kin by the objects continua [0 1900 continuum times exception recombination Astronomical considered, 4-10 n;L account (cf. analyses jet 15 for present jet. a (1981) of the continuum N(C III] agree emission the factor ergs (right-hand 0 ii star, 3 ::> CJJM f- w x~ ~ 3 A eta/. reddening. Johnson less ~ times = wavelength The -:0 ~ ~<( by spectra ."' is ~ contribution jet e> Q) E " IV)= to 3 4.3 but cm- for for closely not in 10.0 Brugel is greater, intense. 9.0 8.0 5.0 6.0 0.0 3.0 2.0 4.0 (obtained 7.0 For dust-scattered of in similar continuum fluxes greater free-free X alone. these the 1200 at [SWP n Si lf-F-.LUo.-11f-+KIIH'ft'llll-t-lf'--+--'-!...LIIYHI-'---"'-tl'---''--...J....\~ 2 satisfactorily level. scale) 1982), 1, Kafatos, ~ a and ~ 10 wavelengths s- the continuum III] IUE where 2. SII with 55 2-3. I eta/. fashion Society Ly·a SII distribution 1 objects. 16916: shown I Dust and to free-free in is We If In 1300 A-t, carbon cm- A1892, and OI at below), and plotted OBSERVATIONS I lower geocorona the those that They general, N en might is [0 I have A2328 position scattering and 3 assume denotes recombina­ stellar central , a in similar Taking ~ 1400 explained orv] II] suggested appropri­ longward in A factor lines, tempera­ continua obtained which • attribute I Table 5 we ::5 carried different be Hobbs of A2470 Provided emis­ times (a), C con­ 1400 find that WAVELENGTH star UV ap­ Nrv] 1500 the we an I of of II] to and is 2 absolute CIV SWP I T"'"' OF 1600 Fell? losity Wallerstein (1980). could ne(*) We than Assuming with eaie ionic relative n;(*)L nebulosity region object for Ha However, Kafatos, the tinuum n;(jet)L ular unique region E analysis suggest 10 that ties by 16918: (A) 8 R flux Based 4 _ E om] [0 the AQUARII v?: 1700 prefer K. ::5 A6563 8 ne(*)/ne(jet) parameters ~ the units (Kafatos ne(*) _ accommodate position given 3 around m]line 10 way as For (*) observed 2.3 v that The 3 NASA 0 is Nm] (jet) and 9 = observed for on is the that than Te(*) ~ em- X 1800 high a not ~ to and 0.65 observed the the assumed central 4.3 size (b)] Hobbs lower 10 ~ 1.5 the obtain carbon previous for JET strengths. the and abundance. 3 ~ uncertainties possible line 7 4.3 applies, Greenstein in X Astrophysics are s;m] electron in in L the X central ~ 1.5 cm- 1900 He 10 the ~ line shown temperatures, CIII Michalitsianos X 10 intensity the the an central star 10. nebula I 1980), nebular 57 for X 2 X 2 by lines, ] 10 6 3 I central -4 , cm- E 10 The and central 6.0 2.0 A2945 1.0 8.0 3 4.0 jet If 5.0 intensity analysis 7.0 55 for star the .0 8 which for Wallerstein temperatures 10 4 X _ cm- the the (1980) K We we v ii ::> emission 3 0 w ~ --' ~ x~ the agrees are 14 in parameters denser prevailing Te , and 10 ratio = (left-hand star ~ ~0 ~<( compared if '"' size em comparatively jet E 3 Q) ~ line ~ E 6 = ionized find 0.0 is for a Te(jet) 8 Data find jet say and (cf. cm- ratios. _ is 1.5 of of normal 1982), in with of appreciably v arises central E and is probably that the discussed central Si Te 8 measure X the the and scale). 3 similar, that _ Michalitsianos, electron in System the ~ region for III] = 10 with v be central obtained we There line-emitting visible a in = 10 galactic 4 10 the strength Greenstein nebulosity. object. the Al892 The consistent consistent 4 0.0. the K find the 4 Te(jet) flat nebular. we then K and K, earlier. central central spectra higher unless densi­ nebu­ is same from neb­ Note con­ find L49 that and one and law by no jet of ~ is 1982ApJ...262L..47M L50 lower involved substantial einission it line interesting properties formation and conditions C Ininimizing tions tion). used absolute abundances. If corresponds III] © intensities relatively that in calculations N [0 N Si 0 C Fe Fe [~I~]II]} Nv? S Si S ? 0 OI C C Hei He Fe Fe Mgii{h H~~~I~ temperatures ;\.1909 American 0 II II III] II IV III] IV electron III] II III] IV] 0