6828( 7) - 10/25/96 13:36 - [ 0] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 6828 Version: 7 Check-in Date: 25-Oct-1996 13:30:58 1.Proposal Title: Far UV emission spectrum and stellar wind of Sirius A ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Cycle HOT STARS GO 6 ------------------------------------------------------------------------------------ 5. Investigators Contact? PI: Alfred Vidal-Madjar INSTITUT D'ASTROPHYSIQUE DE PARIS CoI: Nicole Allard Observatoire de Paris-Meudon N CoI: Lotfi Ben Jaffel Institut d'Astrophysique de Paris N CoI: Roger Ferlet Institut d'Astrophysique de Paris N CoI: Cecile Gry Laboratoire d'Astronomie Spatiale de N Marseille CoI: Robert Kurucz Smithsonian Astrophysical Observatory N CoI: Henny Lamers Utrecht N ------------------------------------------------------------------------------------ 6. Abstract Our previous HST GHRS observations of the main sequence A1 V star Sirius A have revealed completely unexpected spectral pecularities and physical properties of that well-known star such as the presence of emission features below 1220 Angstrom and the existence of a weak stellar wind. We propose to further observe these emissions to explore their origin and the stellar wind to fill the gap in our knowledge of intermediate stars. ------------------------------------------------------------------------------------ Observations Description ------------------------ We plan to observe Sirius-A and its white dwarf companion with ECH-A, at the highest possible S/N within the number of selected orbits, at \\ly\\ and over the NI triplet at 1200Angstrom\\. This will give access to the interstellar \\ly\\ H and D lines, to the photospheric \\ly\\ line, as well as NI 1199Angstrom, 1200Angstrom, 1201Angstrom and SiIII 1206Angstrom. We plan four other ECH-A settings: OI 1302Angstrom and SiII 1304Angstrom lines; CII and CII^* around 1330 Angstrom; the highly ionized species SiIV, CIV and NV. Information from ECH-B spectra is already available. These observations should perfectly complement our original HST data and allow us to evaluate precisely the \\dsh\\ ratio in these lines of sights., We are aware from our Cycle 1 observations (and others) of some of the difficulties involved in such observations (granularities of the photocathode, importance of frequent calibrations, sampling of the spectrum in 1/4 diode steps). As well, we estimated the scattered light due to Sirius-A when observing Sirius-B to be of minor importance. In effect, using the SSA, the separation between both stars being ~ 3 arcsec in 1996, the ratio of the fluxes F(Sirius-A)/F(Sirius-B) in the spectrograph is much less than 7. 10^-5 times the ratio of the fluxes F(Sirius-A)/F(Sirius-B) in front of the entrance slit, as given by the spatial Post-Costar PSF. Due to the spectral types of both stars, this latter ratio is higher the longer the wavelength, and is only ~100 at 2800Angstrom, which is the far longer than we consider here. Therefore, the contamination by Sirius-A should represent much less than 7. 10^-3 times the signal of Sirius-B, which is clearly negligible. The strong flux of Sirius-B at \\ly\\ allows us to have short exposure times while keeping a high signal-to- noise ratio (S/N ~\\ 40 per diode) at the bottom of the \\ly\\ line, about as well as at the continuum of other observed lines. We obtained flux at each chosen wavelength for Sirius- B from theoretical calculations, as well as from the IUE spectra (Wegner &\\ Swanson, 1991). We converted these fluxes into counts using the sensitivity tables of the instrument and, where appropriate the Ripple function, given in the Post-Costar GHRS Instrument Handbook. These counts were calibrated to the use of the SSA, whose throughput is 2/3 that of the LSA. As an example, the flux at the bottom of the \\ly\\ line (1215.67Angstrom) toward Sirius-B is 2. 10^-12 erg.cm^-2.s^-1.ang^-1. Taken the sensitivity of the ECH-A (order 46) at this wavelength using the SSA, the count rate is therefore sim 0.1 c.s^-1.d^-1, which gives a signal-to- noise ratio S/N ~ 20 per diode in 4000 s. Taking into account the several count rates at 1200Angstrom\\ (Sirius A, 3.0 c.s^- 1.d^-1, Sirius B, 0.72 c.s^-1.d^-1), at 1216Angstrom\\ (Sirius A, 0.56 c.s^-1.d^-1, Sirius B, 0.1 c.s^-1.d^-1), at 1302Angstrom\\ (Sirius A, 380.0 c.s^-1.d^-1, Sirius B, 8.4 c.s^-1.d^-1), the nearby wavelength, and the fact that the flux of Vega is about three times less than the one of Sirius A around \\ly , the only spectral region where Vega will be observed with the G140M, for the purpose of comparison, shows that all the requested exposures translate into 10 orbits including overheads. Real Time Justification ----------------------- There are optimum times in the year (typically a three month window) for obtaining \\ly\\ observations toward white dwarfs. These times are when the velocity of the Earth is such that the geocoronal \\ly\\ emission (arising in the Earth atmosphere) is centered in the core of the \\hi\\ absorption profile, so that it may be easily isolated and removed without affecting the \\di\\ absorption. This strategy has been successfully used for our previous observations of G191-B2B. We will need an accurate acquisition of Sirius-B, due to the presence of Sirius-A, whose flux can be as high as 10 times the flux of Sirius-B at the wavelengths we consider. We estimate this contamination to be negligible if Sirius-B is well centered on the entrance slit. Calibration Justification ------------------------- Additional Comments ------------------- The position of Sirius-B is calculated relative to the Sirius-A one. There are two relatively short observing windows centered on September 10, 1996 and on November 5, 1996. The RA and DEC offsets given correspond to the September 10 centered window. Here are the calculated RA and DEC for the two possible windows: Window centered on September 10, 1996, Sirius-B position should be RA = 06H 45M 08.796S +/- 0.03", DEC = -16D 43' 01.49" +/- 0.04" Window centered on November 5, 1996, Sirius-B position should be RA = 06H 45M 08.806S +/- 0.03", DEC = -16D 43' 01.57" +/- 0.04" Note that the RPS2 calculation produces a slightly different estimation of the declination. The RA and DEC given are from the Hipparcos catalogue. The RPS2 software does not accept an Epoch later than 1996.1, although it seems that the Epoch of the catalogue seems to be 2000. This is why the value 1996 was arbitrarily put in, since I was unable to figure out to what evaluation of the Epoch I should refer, corresponding to the used catalogue, some information leading to 1990, and others to year 2000. ------------------------------------------------------------------------------------ Data Distribution Media: 8MM Blocking Factor: 10 Ship To: PI_Address Ship Via: UPS Email: , ------------------------------------------------------------------------------------ 6828( 7) - 10/25/96 13:36 - [ 1] TARGET LIST a) Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 HD48915- STAR, A0-A3 V-IV RA = 06H 45M 08.88S +/- 0.03", J2000 V = -7.6 V = -1.45+/-0.01 OFFSET DEC = -16D 42' 56.9" +/- 0.04" B-V = 0.009 F(1199)=5.+/-1.e-11 F(1206)=2.5+/-1.e-11 F(1215)=1.+/-0.5e-11 F(1302)=5.+/-1.e-09 F(1334)=1.+/-1.e-09 Comments: Binary at 3.69", V=8.9 THE COORDINATES ARE FROM HIPPARCOS CATALOGUE. Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 2000 -0.038 -1.205 0.374 2 SIRIUS-B STAR, DA RA-OFF = -0.0753S +/- 0.006S, J2000 V = -3 V = 8.9+/-0.2 DEC-OFF = -3.50" +/- 0.045", B-V = -0.12 FROM 1 F(1199)=2.6+/-0.5e-11 F(1206)=1.7+/-0.5e-11 F(1215)=2.5+/-1.e-12 F(1302)=1.2+/-1.e-10 F(1334)=1.2+/-1.e-10 Comments: ON SEPT 10, POSITION ANGLE=197.19 DEG, OFFSET FROM SIRIUS-A IS 3.67 ARCSEC. GIVEN POSITIONS CORRESPOND TO SEPT 10. SHOULD BE APPLIED TO FIRST OBSERVING WINDOW. ON NOV 5, POSITION ANGLE=194.52 DEG, OFFSET FROM SIRIUS-A IS 3.70 ARCSEC. FOR THE SECOND OBSERVING WINDOW, POSITIONS ARE: RA-OFF = -0.0646S, DEC-OFF = - 3.58". 3 HD172167 STAR, A0-A3 V-IV RA = 18H 36M 56.33S +/- 0.3", J2000 V = -14 V = 0.033+/-0.01 DEC = +38D 47' 01.2" +/- 0.3" B-V = 0.001+/-0.005 F(1199)=1.+/-0.5e-10 F(1206)=2.+/-0.5e-10 F(1215)=1.+/-0.5e-10 F(1302)=2.+/-0.5e-9 F(1334)=3.+/-0.5e-9 Comments: THE COORDINATES ARE FROM HIPPARCOS CATALOGUE. Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 2000 0.0173 0.286 0.123 4 SIRIUS-B-51 STAR, DA RA-OFF = -0.0620S +/- 0.006S, J2000 V = -3 V = 8.9+/-0.2 DEC-OFF = -3.60" +/- 0.045", B-V = -0.12 FROM 1 F(1199)=2.6+/-0.5e-11 F(1206)=1.7+/-0.5e-11 F(1215)=2.5+/-1.e-12 F(1302)=1.2+/-1.e-10 F(1334)=1.2+/-1.e-10 Comments: New offset calculated for repeat visit 51 for 11/18/96 timeframe 6828( 7) - 10/25/96 13:36 - [ 2] Visit: 01 Visit Requirements: BETWEEN 31-AUG-96 AND 26-SEP-96 On Hold Comments: Additional Comments: Dates to avoid geocorona. Second choice is between 10/26-11/21/96 Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 9 HD48915-OFF HRS ACQ 2.0 MIRROR-A1 SEARCH-SIZE=3,BRIGHT=RETURN, 1 1.8 S ONBOARD ACQ FOR 10 SET LOCATE=YES Comments: STEP-TIME=0.2S ------------------------------------------------------------------------------------------------------------------------------------ 10 HD48915-OFF HRS ACQ/PEA 0.25 MIRROR-A1 SEARCH-SIZE=5 1 5 S ONBOARD ACQ FOR 11 SET KUP Comments: STEP-TIME=0.2S ------------------------------------------------------------------------------------------------------------------------------------ 11 HD48915-OFF HRS ACQ/PEA 0.25 MIRROR-A1 SEARCH-SIZE=5 1 5 S ONBOARD ACQ FOR 12-134 SET KUP Comments: STEP-TIME=0.2S ------------------------------------------------------------------------------------------------------------------------------------ 12 SIRIUS-B HRS ACQ/PEA 0.25 MIRROR-N1 SEARCH-SIZE=5 1 15 S ONBOARD ACQ FOR 102-134 KUP Comments: STEP-TIME=0.6S, EXPECTED COUNT RATE=16500 S-1 ------------------------------------------------------------------------------------------------------------------------------------ 102 WAVE HRS ACCUM SC2 ECH-A 1335.0 SPYBAL=YES 1 DEF Comments: WAVE CALIBRATION FOR 103 ------------------------------------------------------------------------------------------------------------------------------------ 103 SIRIUS-B HRS ACCUM 0.25 ECH-A 1335.0 FP-SPLIT=STD,STEP-PATT=DEF 2 108.8 S Comments: C II, C II* ------------------------------------------------------------------------------------------------------------------------------------ 105 WAVE HRS ACCUM SC2 ECH-A 1302.0 SPYBAL=YES 1 DEF Comments: WAVE CALIBRATION FOR 106 ------------------------------------------------------------------------------------------------------------------------------------ 106 SIRIUS-B HRS ACCUM 0.25 ECH-A 1302.0 FP-SPLIT=STD,STEP-PATT=DEF 2 108.8 S Comments: O I, Si II ------------------------------------------------------------------------------------------------------------------------------------ 112 WAVE HRS ACCUM SC2 ECH-A 1215.6 SPYBAL=YES 1 DEF Comments: WAVE CALIBRATION FOR 113 ------------------------------------------------------------------------------------------------------------------------------------ 113 SIRIUS-B HRS ACCUM 0.25 ECH-A 1215.6 FP-SPLIT=STD,STEP-PATT=DEF, 5 435.2 S SPYBAL=NO Comments: H I, D I ------------------------------------------------------------------------------------------------------------------------------------ 115 WAVE HRS ACCUM SC2 ECH-A 1204.75 SPYBAL=YES 1 DEF Comments: WAVE CALIBRATION FOR 116 ------------------------------------------------------------------------------------------------------------------------------------ 116 SIRIUS-B HRS ACCUM 0.25 ECH-A 1204.75 FP-SPLIT=STD,STEP-PATT=DEF, 4 435.2 S SPYBAL=NO Comments: Si III ------------------------------------------------------------------------------------------------------------------------------------ 128 SIRIUS-B HRS ACCUM 0.25 G140M 1202.75 FP-SPLIT=STD,STEP-PATT=DEF 3 544.0 S Comments: HI, DI ------------------------------------------------------------------------------------------------------------------------------------ 6828( 7) - 10/25/96 13:36 - [ 3] Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 131 SIRIUS-B HRS ACCUM 0.25 G140M 1293.0 FP-SPLIT=STD,STEP-PATT=DEF 3 108.8 S Comments: OI, SiII ------------------------------------------------------------------------------------------------------------------------------------ 134 SIRIUS-B HRS ACCUM 0.25 G140M 1322.5 FP-SPLIT=STD,STEP-PATT=DEF 2 108.8 S Comments: CII , CII* ------------------------------------------------------------------------------------------------------------------------------------ 6828( 7) - 10/25/96 13:36 - [ 4] Visit: 02 Visit Requirements: BETWEEN 1-AUG-96 AND 31-DEC-96 On Hold Comments: Additional Comments: Dates to avoid geocorona Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 210 HD172167 HRS ACQ 2.0 MIRROR-A1 SEARCH-SIZE=3,BRIGHT=RETURN, 1 1.8 S ONBOARD ACQ FOR 211 LOCATE=YES Comments: STEP-TIME=0.2S ------------------------------------------------------------------------------------------------------------------------------------ 211 HD172167 HRS ACQ/PEA 0.25 MIRROR-A1 SEARCH-SIZE=5 1 5 S ONBOARD ACQ FOR 212 KUP Comments: STEP-TIME=0.2S ------------------------------------------------------------------------------------------------------------------------------------ 212 HD172167 HRS ACQ/PEA 0.25 MIRROR-A1 SEARCH-SIZE=5 1 5 S ONBOARD ACQ FOR 228-234 KUP Comments: STEP-TIME=0.2S ------------------------------------------------------------------------------------------------------------------------------------ 228 HD172167 HRS ACCUM 0.25 G140M 1204.0 FP-SPLIT=STD,STEP-PATT=DEF 2 217.6 S Comments: HI, DI ------------------------------------------------------------------------------------------------------------------------------------ 231 HD172167 HRS ACCUM 0.25 G140M 1293.0 FP-SPLIT=STD,STEP-PATT=DEF 1 108.8 S Comments: OI, SIII ------------------------------------------------------------------------------------------------------------------------------------ 234 HD172167 HRS ACCUM 0.25 G140M 1322.5 FP-SPLIT=STD,STEP-PATT=DEF 1 108.8 S Comments: CII , CII* ------------------------------------------------------------------------------------------------------------------------------------ 6828( 7) - 10/25/96 13:36 - [ 5] Visit: 51 Visit Requirements: On Hold Comments: Additional Comments: HOPR repeat of Visit 1 Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 9 HD48915-OFF HRS ACQ 2.0 MIRROR-A2 SEARCH-SIZE=5,BRIGHT=RETURN, 1 5.0 S ONBOARD ACQ FOR 10 SET LOCATE=YES Comments: STEP-TIME=0.2S ------------------------------------------------------------------------------------------------------------------------------------ 10 HD48915-OFF HRS ACQ/PEA 0.25 MIRROR-A2 SEARCH-SIZE=5 1 5 S ONBOARD ACQ FOR 12 SET KUP Comments: STEP-TIME=0.2S ------------------------------------------------------------------------------------------------------------------------------------ 12 SIRIUS-B-51 HRS ACQ/PEA 0.25 MIRROR-N1 SEARCH-SIZE=5 1 15 S ONBOARD ACQ FOR 13 KUP Comments: STEP-TIME=0.6S, EXPECTED COUNT RATE=16500 S-1 FOR N1 ------------------------------------------------------------------------------------------------------------------------------------ 13 SIRIUS-B-51 HRS ACQ/PEA 0.25 MIRROR-N1 SEARCH-SIZE=5 1 15 S ONBOARD ACQ FOR 102-131 KUP Comments: STEP-TIME=0.6S, EXPECTED COUNT RATE=16500 S-1 FOR N1 ------------------------------------------------------------------------------------------------------------------------------------ 102 WAVE HRS ACCUM SC2 ECH-A 1335.0 SPYBAL=YES 1 DEF Comments: WAVE CALIBRATION FOR 103 ------------------------------------------------------------------------------------------------------------------------------------ 103 SIRIUS-B-51 HRS ACCUM 0.25 ECH-A 1335.0 FP-SPLIT=STD,STEP-PATT=DEF 2 108.8 S Comments: C II, C II* ------------------------------------------------------------------------------------------------------------------------------------ 105 WAVE HRS ACCUM SC2 ECH-A 1302.0 SPYBAL=YES 1 DEF Comments: WAVE CALIBRATION FOR 106 ------------------------------------------------------------------------------------------------------------------------------------ 106 SIRIUS-B-51 HRS ACCUM 0.25 ECH-A 1302.0 FP-SPLIT=STD,STEP-PATT=DEF 2 108.8 S Comments: O I, Si II ------------------------------------------------------------------------------------------------------------------------------------ 112 WAVE HRS ACCUM SC2 ECH-A 1215.6 SPYBAL=YES 1 DEF Comments: WAVE CALIBRATION FOR 113 ------------------------------------------------------------------------------------------------------------------------------------ 113 SIRIUS-B-51 HRS ACCUM 0.25 ECH-A 1215.6 FP-SPLIT=STD,STEP-PATT=DEF, 5 435.2 S SPYBAL=NO Comments: H I, D I ------------------------------------------------------------------------------------------------------------------------------------ 115 WAVE HRS ACCUM SC2 ECH-A 1204.75 SPYBAL=YES 1 DEF Comments: WAVE CALIBRATION FOR 116 ------------------------------------------------------------------------------------------------------------------------------------ 116 SIRIUS-B-51 HRS ACCUM 0.25 ECH-A 1204.75 FP-SPLIT=STD,STEP-PATT=DEF, 4 435.2 S SPYBAL=NO Comments: Si III ------------------------------------------------------------------------------------------------------------------------------------ 125 SIRIUS-B-51 HRS ACCUM 0.25 G140M 1293.0 FP-SPLIT=STD,STEP-PATT=DEF 2 108.8 S Comments: OI, SiII ------------------------------------------------------------------------------------------------------------------------------------ 6828( 7) - 10/25/96 13:36 - [ 6] Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 128 SIRIUS-B-51 HRS ACCUM 0.25 G140M 1322.5 FP-SPLIT=STD,STEP-PATT=DEF 2 108.8 S Comments: CII , CII* ------------------------------------------------------------------------------------------------------------------------------------ 131 SIRIUS-B-51 HRS ACCUM 0.25 G140M 1204.0 FP-SPLIT=STD,STEP-PATT=DEF 4 435.2 S Comments: HI, DI ------------------------------------------------------------------------------------------------------------------------------------ 6828( 7) - 10/25/96 13:36 - [ 7] Visit: 52 Visit Requirements: BEFORE 31-DEC-96 On Hold Comments: Additional Comments: HOPR repeat of Visit 2 Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 210 HD172167 HRS ACQ 2.0 MIRROR-A2 SEARCH-SIZE=5,BRIGHT=RETURN, 1 5.0 S ONBOARD ACQ FOR 211 LOCATE=YES Comments: STEP-TIME=0.2S ------------------------------------------------------------------------------------------------------------------------------------ 211 HD172167 HRS ACQ/PEA 0.25 MIRROR-A2 SEARCH-SIZE=5 1 5 S ONBOARD ACQ FOR 228-234 KUP Comments: STEP-TIME=0.2S ------------------------------------------------------------------------------------------------------------------------------------ 228 HD172167 HRS ACCUM 0.25 G160M 1293.0 FP-SPLIT=STD,STEP-PATT=DEF 1 108.8 S Comments: OI, SIII ------------------------------------------------------------------------------------------------------------------------------------ 231 HD172167 HRS ACCUM 0.25 G160M 1322.5 FP-SPLIT=STD,STEP-PATT=DEF 1 108.8 S Comments: CII , CII* ------------------------------------------------------------------------------------------------------------------------------------ 234 HD172167 HRS ACCUM 0.25 G160M 1204.0 FP-SPLIT=STD,STEP-PATT=DEF 2 217.6 S Comments: HI, DI ------------------------------------------------------------------------------------------------------------------------------------ 6828( 7) - 10/25/96 13:36 - [ 8] Summary Form for Proposal 6828 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations HRS ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACQ ACQ/PEAKUP ACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters SEARCH-SIZE=3 BRIGHT=RETURN LOCATE=YES SEARCH-SIZE=5 SPYBAL=YES STEP-PATT=DEF FP-SPLIT=STD SPYBAL=NO ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category HOT STARS ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements BETWEEN 31-AUG-96 AND 26-SEP-96 ONBOARD ACQ FOR 10 ONBOARD ACQ FOR 11 ONBOARD ACQ FOR 12-134 ONBOARD ACQ FOR 102-134 BETWEEN 1-AUG-96 AND 31-DEC-96 ONBOARD ACQ FOR 211 ONBOARD ACQ FOR 212 ONBOARD ACQ FOR 228-234 ONBOARD ACQ FOR 12 ONBOARD ACQ FOR 13 ONBOARD ACQ FOR 102-131 BEFORE 31-DEC-96 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements MIRROR-A1 MIRROR-N1 ECH-A G140M MIRROR-A2 G160M ------------------------------------------------------------------------------------------------------------------------------------ Target Names HD48915-OFFSET SIRIUS-B WAVE HD172167 SIRIUS-B-51 ------------------------------------------------------------------------------------------------------------------------------------