7487( 13) - 03/12/98 15:28 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 7487 Version: 13 Check-in Date: 12-Mar-1998 15:27:49 1.Proposal Title: Orbits of Pre-Main Sequence Binaries ------------------------------------------------------------------------------------ 2. Proposal For 3. Cycle GO 7 ------------------------------------------------------------------------------------ 4. Investigators Contact? PI: MICHAL SIMON State University of New York, Stony Brook CoI: Sherie Holfeltz Space Telescope Science Institute N CoI: Laurence Taff Johns Hopkins University N ------------------------------------------------------------------------------------ 5. Abstract Our goal is to measure the masses of low mass pre-main sequence stars dynamically. This is important because there are still no low mass young stars with reliably known masses. We have begun to map the orbits of young star binaries in Taurus using the FGS. We propose to continue to measure the orbits of the systems we have determined to have the smallest angular separations. These may be expected to have the shortest periods and are uniquely observable by the HST. ------------------------------------------------------------------------------------ 7487( 13) - 03/12/98 15:28 - [ 2] Observations Description ------------------------ Our program requires the FGS operating in Transfer Function mode. We will use the Pupil filter to take advantage of the red spectra of the stars and the S20 response of the FGS photomultipliers, and the 2/3 aperture stop to achieve the best S/N ratio. The binaries are expected to have orbital periods of a few years so we request two observations per year, at the greatest interval set by guide star availability (see next section). We calculate the exposure time to reach adequate S/N for a V = 17 mag secondary and need an FGS scan of 1.5'' per axis to be certain to include the entire system. To satisfy these constraints we require 10 Transfer Function mode scans at 180 seconds/scan. In practice, we have found that we can fit ~ 2100 seconds of observation into an orbit and have obtained satisfactory data. Real Time Justification ----------------------- Since the stars are in the Taurus dark cloud region, guide star availability is, in principle, an intrinsic problem. HST has, however, observed each of the binaries requested for this program several times now. The guide stars and time - windows of observability have already been identified by Denise Taylor and the problem is not an issue for the targets we propose. Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ Data Distribution Media: DAT Blocking Factor: 10 Ship To: Dr. Michal Simon*Astronomy Program*SUNY*Stony Brook, NY 11794-2100 Ship Via: Email: ------------------------------------------------------------------------------------ 7487( 13) - 03/12/98 15:28 - [ 3] TARGET LIST a) Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 DF-TAU STAR, T Tauri Star RA=04H 27M 2.80S +/- 0.1S, J2000 V = 12.6+/-1.0 DEC=25D 42' 23.1" +/- 1.0", B-V = 0.9+/-0.2 PLATE-ID=000L Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 1983.0 0.0 -0.01 0.0 2 ZZ-TAU STAR, T Tauri Star RA=4H 30M 51.39S +/- 0.1S, J2000 V = 14.5+/-1.0 DEC=24D 42' 22.5" +/- 1.0", B-V = 1.5+/-0.2 PLATE-ID=000L Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 1983.0 0.0007 -0.014 0.0 3 HV-TAU STAR, T Tauri Star RA=4H 38M 35.27S +/- 0.1S, J2000 V = 14.5+/-1.0 DEC=26D 10' 38.9" +/- 1.0", B-V = 1.7+/-0.2 PLATE-ID=000L Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 1983.0 0.0004 -0.031 0.0 4 ELIAS-12 STAR, T Tauri Star RA=4H 33M 6.62S +/- 0.1S, DEC= J2000 V = 12.1+/-1.0 24D 9' 55.2" +/- 1.0", PLATE- B-V = 1.3 ID=000L Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 1983.0 0.0 0.0 0.0 7487( 13) - 03/12/98 15:28 - [ 4] Visit: 01 Visit Priority: Visit Requirements: BETWEEN 15-SEP-1997 AND 13-OCT-1997 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 DF-TAU FGS TRANS PRIME PUPIL STEP-SIZE=0.3,SCANS=14 1 2100 S ------------------------------------------------------------------------------------------------------------------------------------ 7487( 13) - 03/12/98 15:28 - [ 5] Visit: 02 Visit Priority: Visit Requirements: BETWEEN 1-FEB-1998 AND 31-MAR-1998 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 DF-TAU FGS TRANS PRIME PUPIL STEP-SIZE=0.3,SCANS=14 1 2100 S ------------------------------------------------------------------------------------------------------------------------------------ 7487( 13) - 03/12/98 15:28 - [ 6] Visit: 03 Visit Priority: Visit Requirements: BETWEEN 1-JAN-1998 AND 31-MAR-1998 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 ZZ-TAU FGS TRANS PRIME PUPIL STEP-SIZE=0.3,SCANS=14 1 2100 S GS ACQ SCENARIO SINGLE ------------------------------------------------------------------------------------------------------------------------------------ 7487( 13) - 03/12/98 15:28 - [ 7] Visit: 04 Visit Priority: Visit Requirements: AFTER 3 BY 175D TO 180D 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 ZZ-TAU FGS TRANS PRIME PUPIL STEP-SIZE=0.3,SCANS=14 1 2100 S GS ACQ SCENARIO SINGLE ------------------------------------------------------------------------------------------------------------------------------------ 7487( 13) - 03/12/98 15:28 - [ 8] Visit: 05 Visit Priority: Visit Requirements: BEFORE 15-SEP-1997 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 HV-TAU FGS TRANS PRIME PUPIL STEP-SIZE=0.3,SCANS=14 1 2100 S ------------------------------------------------------------------------------------------------------------------------------------ 7487( 13) - 03/12/98 15:28 - [ 9] Visit: 06 Visit Priority: Visit Requirements: BETWEEN 6-NOV-1997 AND 1-JAN-1998 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 HV-TAU FGS TRANS PRIME PUPIL STEP-SIZE=0.3,SCANS=14 1 2100 S ------------------------------------------------------------------------------------------------------------------------------------ 7487( 13) - 03/12/98 15:28 - [ 10] Visit: 07 Visit Priority: Visit Requirements: BETWEEN 1-JUL-1997 AND 15-AUG-1997 ORIENT 218D TO 258D On Hold Comments: Additional Comments: Adjust orient as in cycle 6 to schedule. Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 ELIAS-12 FGS TRANS PRIME PUPIL STEP-SIZE=0.3,SCANS=14 1 2100 S GS ACQ SCENARIO SINGLE ------------------------------------------------------------------------------------------------------------------------------------ 7487( 13) - 03/12/98 15:28 - [ 11] Visit: 08 Visit Priority: Visit Requirements: BETWEEN 1-NOV-1997 AND 1-JAN-1998 ORIENT 218D TO 258D On Hold Comments: Additional Comments: Adjust orient as in cycle 6 to schedule. Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 ELIAS-12 FGS TRANS PRIME PUPIL STEP-SIZE=0.3,SCANS=14 1 2100 S ------------------------------------------------------------------------------------------------------------------------------------ 7487( 13) - 03/12/98 15:28 - [ 12] Summary Form for Proposal 7487 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations FGS ------------------------------------------------------------------------------------------------------------------------------------ Opmodes TRANS ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters STEP-SIZE=0.3 SCANS=14 ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements BETWEEN 15-SEP-1997 AND 13-OCT-1997 BETWEEN 1-FEB-1998 AND 31-MAR-1998 BETWEEN 1-JAN-1998 AND 31-MAR-1998 GS ACQ SCENARIO SINGLE AFTER 3 BY 175D TO 180D BEFORE 15-SEP-1997 BETWEEN 6-NOV-1997 AND 1-JAN-1998 BETWEEN 1-JUL-1997 AND 15-AUG-1997 ORIENT 218D TO 258D BETWEEN 1-NOV-1997 AND 1-JAN-1998 ORIENT 218D TO 258D ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements PUPIL ------------------------------------------------------------------------------------------------------------------------------------ Target Names DF-TAU ZZ-TAU HV-TAU ELIAS-12 ------------------------------------------------------------------------------------------------------------------------------------