9329( 8) - 04/02/03 06:30 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 9329 Version: 8 Check-in Date: 02-Apr-2003 06:27:50 1.Proposal Title: The Masses and Luminosities of Population II Stars ------------------------------------------------------------------------------------ 2. Proposal For 3. Cycle GO 11 ------------------------------------------------------------------------------------ 4. Investigators Contact? PI: Elliott Horch Rochester Institute of Technology CoI: Prof. James Heasley University of Hawaii N CoI: Dr. Otto Franz Lowell Observatory N CoI: Dr. Lawrence Wasserman Lowell Observatory N ------------------------------------------------------------------------------------ 5. Abstract Very little is currently known concerning the mass-luminosity relation (MLR) of Population II stars. However, with the advent of the Hipparcos Catalogue, improved distances to many spectroscopic binaries known to be Pop II systems are now available. After surveying the literature and making reasonable estimates of the secondary masses, we find 13 systems whose minimum separation should be larger than the resolution limit of FGS1. Because of the expected magnitude differences and separations, it is not possible to resolve the systems from the ground. We therefore propose FGS observations of the sample. In combination with the known spectroscopic orbits and Hipparcos distances, these observations will yield up to 26 precise stellar mass determinations of metal-poor stars, if all systems are resolved and the relative orbits are determined. A combination of FGS data and ground-based observations will lead to component luminosities and effective temperatures. This program will allow for a significantly better understanding of the Pop II main sequence, which in turn will lead to better ages and distances of the galactic globular clusters, and a Pop II MLR will be constructed for the first time. ------------------------------------------------------------------------------------ 9329( 8) - 04/02/03 06:30 - [ 2] Observations Description ------------------------ The goal of this project is the robust determination of the relative orbit of each of the thirteen target binaries from 5 resolved observations over the course of the orbit. A minimum of three resolved observations is necessary per object to obtain a relative orbit, but the additional data points will provide significantly better constraints on the orbital parameters, and hence the masses. We feel that, especially considering the magnitude differences anticipated from these systems (3 to 5 in most cases), the overdetermination is entirely warranted for this program. These observations, used in combination with Hipparcos parallaxes and spectroscopic orbits, will yield individual masses for the components. FGS1 will also provide the magnitude difference, which together with the known system luminosities and other data will give individual component luminosity information. The precision of the magnitude differences obtained over the course of the program will be ~ 0.1 mag or better for each system. Each observation of each target will consist of approximately 60 consecutive TRANS scans through filter F5ND for stars brighter than V=8.0, and through F583W for the fainter targets. Co-addition of 60 cross-correlated scans will yield a signal-to-noise ratio (SNR) of approximately 10 for a target of V ~ 16, which is an approximate value for the faintest secondary that we anticipate. Such a companion- magnitude implies a component magnitude difference Delta m <=q 5 mag for 6 of our targets, and a maximum Delta m ~ 7.9 for the brightest target observable through the F583W filter. At Delta m ~ 5, previous experience with FGS indicates that it will be the goodness-of-fit for the bright component, i.e.\ the color calibration of the template and its match to the target color, and not the SNR that will begin to dominate the ability to detect a companion. However, we anticipate that this will be an issue only if a secondary is simultaneously very faint and very close to the primary. We propose to use 5 Cycle-10 visits for each of the 6 targets with period <=q 1 year, and 3 visits for each of the 7 targets of longer period, bringing our request of Cycle-10 to a total of 51 HST orbits. To analyze the TRANS observations of the targets, we will use ``single''-star TRANS scans from the FGS calibration data base as templates. For each of the 5 targets of orbital period in the range 1 <=q P <=q 3 years, we request 2 additional visits during Cycle-11. Four Cycle-12 visits will also be required to complete this work for the two targets with periods longer than 3 years. We plan to supplement the FGS observations with ground-based infrared photometry to constrain the values of rmT_ eff for the cool secondary stars. We will use the facility infrared cameras at the NASA-IRTF and/or the United Kingdom Infrared Telescope (UKIRT) on Mauna Kea for the L band photometry of our targets. The University of Hawaii, home institution of one of the co-investigators (J. H.), has access to both telescopes. In addition, we will obtain infrared spectroscopy of our single-lined systems in order to attempt to measure the radial velocities of the cool, red secondary stars. Mazeh et al.\ (2000) have illustrated the power of this technique for studying main-sequence binary stars and deriving some of the smallest mass ratios ever derived for spectroscopic binaries. We plan to carry out the infrared spectroscopy with the CSHELL and/or CGS4 spectrometers at the IRTF and UKIRT respectively. If we are able to determine the radial velocities of the secondary stars, these systems will be overconstrained in the same way as the double lined spectroscopic binary HD 157948 discussed above. Real Time Justification 9329( 8) - 04/02/03 06:30 - [ 3] ----------------------- For the most precise orbital determinations, it will be necessary to spread out our observations in orbital phase. In the event of a Phase 2 submittal for this proposal, care will be taken to specify time critical observing windows that will assure to the greatest extent possible optimal orbital coverage for each target. None. Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ 9329( 8) - 04/02/03 06:30 - [ 4] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 2 HD64606 STAR, Composite RA= 07H 54M 34.33S +/- .05S, J2000 V = 7.44 Spectral Type DEC=-01D 24' 43.6" +/- .5" B-V = 0.73 Coordinate Source: HIPPARCOS/TYCHO_CATALOGUE Comments: This is an SB1. Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 1991.25 -0.0168 -0.062 .052 3 HD106516 STAR, Composite RA= 12H 15M 10.54S +/- .05S, J2000 V = 6.11 Spectral Type DEC=-10D 18' 35.8" +/- .5" B-V = 0.46 Coordinate Source: HIPPARCOS/TYCHO_CATALOGUE Comments: This is an SB1. Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 1991.25 0.0022 -1.012 .044 6 HD157948 STAR, Composite RA= 17H 24M 42.47S +/- .05S, J2000 V = 8.10 Spectral Type DEC=+38D 02' 12.2" +/- .5" B-V = 0.76 Coordinate Source: HIPPARCOS/TYCHO_CATALOGUE Comments: This is an SB2. Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 1991.25 -0.0054 -0.196 .020 9 HD200580 STAR, Composite RA= 21H 04M 07.55S +/- .05S, J2000 V = 7.33 Spectral Type DEC=+02D 59' 43.4" +/- .5" B-V = 0.53 Coordinate Source: HIPPARCOS/TYCHO_CATALOGUE Comments: This is an SB1. Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 1991.25 -0.0182 -0.369 .018 11 G18-54 STAR, Composite RA= 22H 31M 36.19S +/- .05S, J2000 V = 10.75 Spectral Type DEC=+02D 09' 46.7" +/- .5" B-V = 0.49 Coordinate Source: HIPPARCOS/TYCHO_CATALOGUE Comments: This is an SB1. Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 1991.25 0.0035 -0.329 .009 12 HD218568 STAR, Composite RA= 23H 09M 03.91S +/- .05S, J2000 V = 9.27 Spectral Type DEC=-02D 33' 01.9" +/- .5" B-V = 0.65 Coordinate Source: HIPPARCOS/TYCHO_CATALOGUE Comments: This is an SB1. Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 1991.25 0.0157 0.029 .017 9329( 8) - 04/02/03 06:30 - [ 5] Visit: 01 Visit Priority: Visit Requirements: PCS MODE FINE BETWEEN 18-SEP-2002 AND 05-OCT-2002 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 ------------------------------------------------------------------------------------------------------------------------------------ 10 HD64606 FGS TRANS 1 F5ND SCANS=62,STEP-SIZE=1 1 1550 S POS TARG 0.0, 0.0 ------------------------------------------------------------------------------------------------------------------------------------ 9329( 8) - 04/02/03 06:30 - [ 6] Visit: 02 Visit Priority: Visit Requirements: PCS MODE FINE BETWEEN 25-MAY-2003 AND 06-JUN-2003 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 ------------------------------------------------------------------------------------------------------------------------------------ 10 HD64606 FGS TRANS 1 F5ND SCANS=58,STEP-SIZE=1 1 1450 S POS TARG 0.0, 0.0 ------------------------------------------------------------------------------------------------------------------------------------ 9329( 8) - 04/02/03 06:30 - [ 7] Visit: 03 Visit Priority: Visit Requirements: PCS MODE FINE BETWEEN 25-JAN-2003 AND 10-FEB-2003 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 ------------------------------------------------------------------------------------------------------------------------------------ 10 HD106516 FGS TRANS 1 F5ND SCANS=62,STEP-SIZE=1 1 1550 S POS TARG 0.0, 0.0 ------------------------------------------------------------------------------------------------------------------------------------ 9329( 8) - 04/02/03 06:30 - [ 8] Visit: 04 Visit Priority: Visit Requirements: PCS MODE FINE BETWEEN 15-DEC-2002 AND 31-DEC-2002 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 ------------------------------------------------------------------------------------------------------------------------------------ 10 HD157948 FGS TRANS 1 F583W SCANS=64,STEP-SIZE=1 1 1600 S POS TARG 0.0, 0.0 ------------------------------------------------------------------------------------------------------------------------------------ 9329( 8) - 04/02/03 06:30 - [ 9] Visit: 05 Visit Priority: Visit Requirements: PCS MODE FINE BETWEEN 19-NOV-2003 AND 25-NOV-2003 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 ------------------------------------------------------------------------------------------------------------------------------------ 10 HD157948 FGS TRANS 1 F583W SCANS=64,STEP-SIZE=1 1 1510 S POS TARG 0.0, 0.0 ------------------------------------------------------------------------------------------------------------------------------------ 9329( 8) - 04/02/03 06:30 - [ 10] Visit: 06 Visit Priority: Visit Requirements: PCS MODE FINE BETWEEN 1-DEC-2002 AND 20-DEC-2002 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 ------------------------------------------------------------------------------------------------------------------------------------ 10 HD200580 FGS TRANS 1 F5ND SCANS=62,STEP-SIZE=1 1 1550 S POS TARG 0.0, 0.0 ------------------------------------------------------------------------------------------------------------------------------------ 9329( 8) - 04/02/03 06:30 - [ 11] Visit: 07 Visit Priority: Visit Requirements: PCS MODE FINE BETWEEN 10-MAY-2003 AND 31-MAY-2003 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 ------------------------------------------------------------------------------------------------------------------------------------ 10 HD200580 FGS TRANS 1 F5ND SCANS=62,STEP-SIZE=1 1 1550 S POS TARG 0.0, 0.0 ------------------------------------------------------------------------------------------------------------------------------------ 9329( 8) - 04/02/03 06:30 - [ 12] Visit: 08 Visit Priority: Visit Requirements: PCS MODE FINE BETWEEN 1-OCT-2002 AND 15-OCT-2002 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 ------------------------------------------------------------------------------------------------------------------------------------ 10 G18-54 FGS TRANS 1 F583W SCANS=62,STEP-SIZE=1 1 1550 S POS TARG 0.0, 0.0 ------------------------------------------------------------------------------------------------------------------------------------ 9329( 8) - 04/02/03 06:30 - [ 13] Visit: 09 Visit Priority: Visit Requirements: PCS MODE FINE BETWEEN 15-JUN-2003 AND 30-JUN-2003 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 ------------------------------------------------------------------------------------------------------------------------------------ 10 G18-54 FGS TRANS 1 F583W SCANS=62,STEP-SIZE=1 1 1550 S POS TARG 0.0, 0.0 ------------------------------------------------------------------------------------------------------------------------------------ 9329( 8) - 04/02/03 06:30 - [ 14] Visit: 10 Visit Priority: Visit Requirements: PCS MODE FINE BETWEEN 01-SEP-2002 AND 30-SEP-2002 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 ------------------------------------------------------------------------------------------------------------------------------------ 10 HD218568 FGS TRANS 1 F583W SCANS=58,STEP-SIZE=1 1 1450 S POS TARG 0.0, 0.0 ------------------------------------------------------------------------------------------------------------------------------------ 9329( 8) - 04/02/03 06:30 - [ 15] Summary Form for Proposal 9329 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures 1 ------------------------------------------------------------------------------------------------------------------------------------ Configurations FGS ------------------------------------------------------------------------------------------------------------------------------------ Opmodes TRANS ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters SCANS=62 STEP-SIZE=1 SCANS=58 SCANS=64 ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements PCS MODE FINE BETWEEN 18-SEP-2002 AND 05-OCT-2002 POS TARG 0.0, 0.0 PCS MODE FINE BETWEEN 25-MAY-2003 AND 06-JUN-2003 PCS MODE FINE BETWEEN 25-JAN-2003 AND 10-FEB-2003 PCS MODE FINE BETWEEN 15-DEC-2002 AND 31-DEC-2002 PCS MODE FINE BETWEEN 19-NOV-2003 AND 25-NOV-2003 PCS MODE FINE BETWEEN 1-DEC-2002 AND 20-DEC-2002 PCS MODE FINE BETWEEN 10-MAY-2003 AND 31-MAY-2003 PCS MODE FINE BETWEEN 1-OCT-2002 AND 15-OCT-2002 PCS MODE FINE BETWEEN 15-JUN-2003 AND 30-JUN-2003 PCS MODE FINE BETWEEN 01-SEP-2002 AND 30-SEP-2002 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F5ND F583W ------------------------------------------------------------------------------------------------------------------------------------ Target Names HD64606 HD106516 HD157948 HD200580 G18-54 HD218568 ------------------------------------------------------------------------------------------------------------------------------------