12561( 3) - 18-Nov-2013 14:26:13 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 12561 Version: 3 Check-in Time: 18-Nov-2013 14:26:13 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 Y 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. We have updated the phase2 proposal with a change to the observations to be executed in Jan 2014. Using the "coron" option, we have split the orbit into two visits, each with it own "orient", and a relative roll between the visits of 44 degrees. Combining the data from the two different spacecraft orientations should lead to a reliable determination of the binary position angle and angular separation, which has eluded previous visits since the binary was resolved only along one FGS axis, which left the PA and separations with unusable large errors. 12561( 3) - 18-Nov-2013 14:26:13 - [ 2] Real Time Justification ----------------------- Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ 12561( 3) - 18-Nov-2013 14:26:13 - [ 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( 3) - 18-Nov-2013 14:26:13 - [ 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| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 G006-026BC FGS TRANS 1 F583W SCANS=30, STEP-SIZE=0.3 1 2000 S (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( 3) - 18-Nov-2013 14:26:13 - [ 5] Visit: 02 Visit Requirements: ORIENT 54.0D TO 55.0 D; BETWEEN 26-DEC-2013 AND 16-JAN-2014; VISIBILITY INTERVAL CORON On Hold Comments: Additional Comments: visit 02 and visit 06 are intended to execute within the same HST orbit. Each has its own orient, so there is a roll change between the visits. Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 G006-026BC FGS TRANS 1 F583W SCANS=10, STEP-SIZE=0.6 1 300 S (300 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( 3) - 18-Nov-2013 14:26:13 - [ 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| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 G006-026BC FGS TRANS 1 F583W SCANS=30, STEP-SIZE=0.3 1 2000 S (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( 3) - 18-Nov-2013 14:26:13 - [ 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| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 G006-026BC FGS TRANS 1 F583W SCANS=30, STEP-SIZE=0.3 1 2000 S (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( 3) - 18-Nov-2013 14:26:13 - [ 8] Visit: 06 Visit Requirements: ORIENT 96.0D TO 98.0 D; AFTER 02 BY 0 Orbits TO 1 Orbits; GROUP 06, 02 WITHIN 1H; VISIBILITY INTERVAL CORON 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| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 G006-026BC FGS TRANS 1 F583W SCANS=10, STEP-SIZE=0.6 1 300 S (300 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( 3) - 18-Nov-2013 14:26:13 - [ 9] Summary Form for Proposal 12561 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures 1 ------------------------------------------------------------------------------------------------------------------------------------ Configurations FGS ------------------------------------------------------------------------------------------------------------------------------------ Opmodes TRANS ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters SCANS=10, SCANS=30, STEP-SIZE=0.3, STEP-SIZE=0.6 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements AFTER 02 BY 0 Orbits TO 1 Orbits, BETWEEN 13-FEB-2013 AND 17-FEB-2013, BETWEEN 26-DEC-2013 AND 16-JAN-2014, BETWEEN 29-JAN-2013 AND 03-FEB-2013, BETWEEN 29-OCT-2011 AND 03-NOV-2011, GROUP 06, 02 WITHIN 1H, ORIENT 260.0D TO 262.0 D, ORIENT 54.0D TO 55.0 D, ORIENT 63.0D TO 67.0 D, ORIENT 70.0D TO 74.0 D, ORIENT 96.0D TO 98.0 D, VISIBILITY INTERVAL CORON ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F583W ------------------------------------------------------------------------------------------------------------------------------------ Target Names G006-026BC ------------------------------------------------------------------------------------------------------------------------------------