12561( 2) - 15-Jul-2011 16:36:33 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 12561 Version: 2 Check-in Time: 15-Jul-2011 16:36:33 STScI Edit Number: 0 Title The Weight-Watch Program for Subdwarfs ------------------------------------------------------------------------------------ Type Cycle GO 19 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. Wei-Chun Jao Georgia State University Research Foundation CoI: Dr. Todd J. Henry Georgia State University Research N Foundation CoI: Dr. Edmund Nelan Space Telescope Science Institute N CoI: Dr. Otto G. Franz Lowell Observatory N CoI: Dr. Lawrence H. Wasserman Lowell Observatory N ------------------------------------------------------------------------------------ Abstract The mass-luminosity relation (MLR) is one of the most important map in stellar astronomy. The empirical MLR for dwarfs has been done for many years, but we do not even have enough low metallicity stars, the counterpart of dwarfs, for their MLR. This project of "Weight-Watch Program for Subdwarfs" is to establish such empirical MLR for low metallicity stars. We propose to use HST/FGS1r to finish mapping the visual orbit of one important benchmark low metallicity binary, G006-026. We resolved this double-lined spectroscopic binary in our Cycle 15 HST/FGS program. By combining the SB2 data and our single-epoch HST/FGS1r result, we have estimated their masses and visual orbit, but with errors in excess of 10%. By combining that effort with four additional orbits proposed in Cycle 19, we will reduce the mass errors to 5% (or less) and finish this star's "Weight-Watch program". ------------------------------------------------------------------------------------ Observations Description ------------------------ We will use FGS1r in its high angular resolution observing "TRANS" mode to resolve the tight SB2 binary system G006-026. This system has a semi-major axis of only 23 mas. But given the eccentricity of ~1.5, a favorable viewing angle (little omega), and inclination, carefully timed FGS observations can be executed whereby the projected angular separation of the binary components will exceed a precisely measured ~13 mas on each FGS axis, thereby yielding an accurate component separation and position angle at each observing epoch. The dates of the observations are carefully set to achieve these results. Real Time Justification ----------------------- Calibration Justification ------------------------- Additional Comments 12561( 2) - 15-Jul-2011 16:36:33 - [ 2] ------------------- ------------------------------------------------------------------------------------ 12561( 2) - 15-Jul-2011 16:36:33 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 G006-026BC STAR, POPULATION II RA=03H39M34.9300S +/- 0.1", J2000 V = 12.71 DEC=+18D18'51.80" +/- 0.1" Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 12561( 2) - 15-Jul-2011 16:36:33 - [ 4] Visit: 01 Visit Requirements: ORIENT 260.0D TO 262.0 D; BETWEEN 29-OCT-2011 AND 03-NOV-2011 On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 G006-026BC FGS TRANS 1 F583W SCANS=30, STEP-SIZE=0.3 1 2000 S ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ G006-026BC 1 FGS TRANS 1 F583W none none none none 1 N/A 12561( 2) - 15-Jul-2011 16:36:33 - [ 5] Visit: 02 Visit Requirements: ORIENT 264.0D TO 268.0 D; BETWEEN 19-AUG-2012 AND 21-AUG-2012 On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 G006-026BC FGS TRANS 1 F583W SCANS=30, STEP-SIZE=0.3 1 2000 S ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ G006-026BC 1 FGS TRANS 1 F583W none none none none 1 N/A 12561( 2) - 15-Jul-2011 16:36:33 - [ 6] Visit: 04 Visit Requirements: ORIENT 70.0D TO 74.0 D; BETWEEN 29-JAN-2013 AND 03-FEB-2013 On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 G006-026BC FGS TRANS 1 F583W SCANS=30, STEP-SIZE=0.3 1 2000 S ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ G006-026BC 1 FGS TRANS 1 F583W none none none none 1 N/A 12561( 2) - 15-Jul-2011 16:36:33 - [ 7] Visit: 05 Visit Requirements: ORIENT 63.0D TO 67.0 D; BETWEEN 13-FEB-2013 AND 17-FEB-2013 On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 G006-026BC FGS TRANS 1 F583W SCANS=30, STEP-SIZE=0.3 1 2000 S ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ G006-026BC 1 FGS TRANS 1 F583W none none none none 1 N/A 12561( 2) - 15-Jul-2011 16:36:33 - [ 8] Summary Form for Proposal 12561 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures 1 ------------------------------------------------------------------------------------------------------------------------------------ Configurations FGS ------------------------------------------------------------------------------------------------------------------------------------ Opmodes TRANS ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters SCANS=30, STEP-SIZE=0.3 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements BETWEEN 13-FEB-2013 AND 17-FEB-2013, BETWEEN 19-AUG-2012 AND 21-AUG-2012, BETWEEN 29-JAN-2013 AND 03-FEB-2013, BETWEEN 29-OCT-2011 AND 03-NOV-2011, ORIENT 260.0D TO 262.0 D, ORIENT 264.0D TO 268.0 D, ORIENT 63.0D TO 67.0 D, ORIENT 70.0D TO 74.0 D ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F583W ------------------------------------------------------------------------------------------------------------------------------------ Target Names G006-026BC ------------------------------------------------------------------------------------------------------------------------------------