6644( 4) - 04/22/96 15:35 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 6644 Version: 4 Check-in Date: 22-Apr-1996 15:29:02 1.Proposal Title: Boron Isotope Ratios in Early B Stars from B III ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Cycle HOT STARS GO 6 ------------------------------------------------------------------------------------ 5. Investigators Contact? PI: Charles R. Proffitt Computer Sciences Corporation CoI: David Leckrone NASA/Goddard Space Flight Center N CoI: Per Joensson Vanderbilt University N CoI: Tomas Brage National Research Council/GSFC N CoI: Glenn Wahlgren Computer Sciences Corporation N ------------------------------------------------------------------------------------ 6. Abstract We propose to measure the ^11B/^10B ratio in the early B stars HD 886 (Gamma Peg) and HD 35299, by obtaining very high signal to noise ratio echelle-B spectra of the B III resonance line at 2066.8 Angstrom. Theoretical calculations predict a 42 mA shift between the two isotopes, and both synthetic spectra and high-dispersion IUE spectra show that the line is present in both targets and is suitable for measuring the isotope shift. The solar system ^11B/^10B ratio of 4:1 is considerably larger than the the canonical predictions of cosmic ray spallation theory (about 2.5:1). These observations will allow us to investigate whether or not the solar system abundance ratio is universal among population I stars, and will place new constraints on theories of ^11B synthesis. ------------------------------------------------------------------------------------ 6644( 4) - 04/22/96 15:35 - [ 2] Observations Description ------------------------ The following table summarizes our proposed observations. For the echelle observations we also show the expected S/N ratio obtained after co-addition of the spectra and removal of the granularity and fixed pattern noise. All observations will use the SSA, STEP-PATT=5 or 7, and be broken into subexposures of 5 minutes or less. Except where noted FP-SPLIT=STD will also be used. All acquisitions and peakups can be done in the first orbit of a visit using mirror A2 using a step-size=0.2 sec. For our brighter two targets, the dead time correction during acquisition will reduce the count rate by about a factor of two. Note that for two of our targets we are taking echelle exposures at three central wavelengths, differing by only about an angstrom. This is to allow us to better solve for the granularity and fixed pattern noise. Target grating lambda t_exp Poisson Actual . (Angstrom) (sec) S/N S/N ---------------- ------------------------------------- HD886 ECH-B 2065.0 652.8 286 . 2066.0 761.6 286 . 2067.1 761.6 286 co-addition 500 450 . G160M 1361.2 108.8 262 100 - ---------------------------------------------------- HD35299 ECH-B 2065.0 3 X 870.4 180 . 2066.0 3 X 870.4 180 . 2067.1 3 X 870.4 180 co-addition 310 280 --- -------------------------------------------------- HD3360 G160M 2066 108.8 90 90 . G160M 1361.2 108.8 140 50 FP-SPLIT=DSTWO --------------------------------- -------------------- A four orbit visit is planned for HD35299, two orbits for HD886, and one orbit for HD3360. Real Time Justification ----------------------- Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ Data Distribution Media: 8MM Blocking Factor: 10 Ship To: PI_Address Ship Via: Email: , ------------------------------------------------------------------------------------ 6644( 4) - 04/22/96 15:35 - [ 3] TARGET LIST a) Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 HD886 STAR,B0-B2 V-IV, RA=00H 13M 14.12S +/- J2000.0 V = 4 V = 2.83+/-0.03 0.1",DEC=15D 11' 1.1" +/- 0.1" B-V = -0.23+/-0.02 U-B = -0.86+/-0.03 F(2067)=3.1+/-0.3e-9 F(1362)=1.0+/-0.1e-8 Comments: Hipparcos coordinates from GSC, plate#=56 Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) J2000.0 0.0002 -0.012 0.0 2 HD35299 STAR,B0-B2 V-IV, RA=05H 23M 42.34S +/- 0.09",DEC= J2000.0 V = 22. V = 5.70+/-0.03 -0.1598889D +/- 0.00002D B-V = -0.21+/-0.02 U-B = -0.88+/-0.05 F(2066)=3.0+/-0.1e-10 Comments: Hipparcos coordinates from GSC, plate#=56 Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) J2000.0 0.000 -0.004 0.0 3 HD3360 STAR,B0-B2 V-IV,BE, RA=00H 36M 58.28S +/- J2000.0 V = 2 B-V = -0.20+/-0.01 0.01",DEC=53D 53' 49.0" +/- U-B = -0.84+/-0.03 0.02" V = 3.66+/-0.02 F(2067)=1.7+/-0.2e-9 F(1362)=4.5+/-0.4e-9 Comments: Hipparcos coordinates from GSC, plate#=56 Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) J2000.0 0.0022 -0.005 0.007 6644( 4) - 04/22/96 15:35 - [ 4] Visit: 01 Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 110 HD886 HRS ACQ 2.0 MIRROR-A2 BRIGHT=RETURN 1 1.8S ONBOARD ACQ FOR 120 Comments: STEP-TIME = 0.2 SEC, 6e4 cnts/step after dead time corr. ------------------------------------------------------------------------------------------------------------------------------------ 120 HD886 HRS ACQ/PEA 0.25 MIRROR-A2 SEARCH-SIZE=5 1 5.0S ONBOARD ACQ FOR 130-160 KUP Comments: STEP-TIME = 0.2 SEC ------------------------------------------------------------------------------------------------------------------------------------ 130 HD886 HRS ACCUM 0.25 G160M 1361.2 FP-SPLIT=STD 1 108.8S ------------------------------------------------------------------------------------------------------------------------------------ 140 HD886 HRS ACCUM 0.25 ECH-B 2066.0 FP-SPLIT=STD 1 761.6S ------------------------------------------------------------------------------------------------------------------------------------ 150 HD886 HRS ACCUM 0.25 ECH-B 2067.1 FP-SPLIT=STD 1 761.6S ------------------------------------------------------------------------------------------------------------------------------------ 160 HD886 HRS ACCUM 0.25 ECH-B 2065.0 FP-SPLIT=STD 1 652.8S ------------------------------------------------------------------------------------------------------------------------------------ 6644( 4) - 04/22/96 15:35 - [ 5] Visit: 02 Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 210 HD35299 HRS ACQ 2.0 MIRROR-A2 BRIGHT=RETURN 1 1.8S ONBOARD ACQ FOR 220 Comments: STEP-TIME = 0.2 SEC, 1.5e4 cnts/step-time expected. ------------------------------------------------------------------------------------------------------------------------------------ 220 HD35299 HRS ACQ/PEA 0.25 MIRROR-A2 SEARCH-SIZE=5 1 5.0S ONBOARD ACQ FOR 230-250 KUP ------------------------------------------------------------------------------------------------------------------------------------ 230 HD35299 HRS ACCUM 0.25 ECH-B 2066.0 FP-SPLIT=STD 3 870.4S ------------------------------------------------------------------------------------------------------------------------------------ 240 HD35299 HRS ACCUM 0.25 ECH-B 2067.1 FP-SPLIT=STD 3 870.4S ------------------------------------------------------------------------------------------------------------------------------------ 250 HD35299 HRS ACCUM 0.25 ECH-B 2065.0 FP-SPLIT=STD 3 870.4S ------------------------------------------------------------------------------------------------------------------------------------ 6644( 4) - 04/22/96 15:35 - [ 6] Visit: 03 Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 310 HD3360 HRS ACQ 2.0 MIRROR-A2 BRIGHT=RETURN 1 1.8S ONBOARD ACQ FOR 320 Comments: STEP-TIME = 0.2 SEC, 3e4 counts/step after dead time corr. ------------------------------------------------------------------------------------------------------------------------------------ 320 HD3360 HRS ACQ/PEA 0.25 MIRROR-A2 SEARCH-SIZE=5 1 5.0S ONBOARD ACQ FOR 330-340 KUP ------------------------------------------------------------------------------------------------------------------------------------ 330 HD3360 HRS ACCUM 0.25 G160M 2066.0 FP-SPLIT=STD 1 108.8S ------------------------------------------------------------------------------------------------------------------------------------ 340 HD3360 HRS ACCUM 0.25 G160M 1361.2 FP-SPLIT=DSTWO 1 108.8S ------------------------------------------------------------------------------------------------------------------------------------ 6644( 4) - 04/22/96 15:35 - [ 7] Summary Form for Proposal 6644 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations HRS ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACQ ACQ/PEAKUP ACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters BRIGHT=RETURN SEARCH-SIZE=5 FP-SPLIT=STD FP-SPLIT=DSTWO ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category HOT STARS ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ONBOARD ACQ FOR 120 ONBOARD ACQ FOR 130-160 ONBOARD ACQ FOR 220 ONBOARD ACQ FOR 230-250 ONBOARD ACQ FOR 320 ONBOARD ACQ FOR 330-340 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements MIRROR-A2 G160M ECH-B ------------------------------------------------------------------------------------------------------------------------------------ Target Names HD886 HD35299 HD3360 ------------------------------------------------------------------------------------------------------------------------------------