Page 1 PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID 2938c Report Date: 09-May-96:17:38 Version: ********** Check-in Date: ********** 1.Proposal Title: UNSEEN AND PLANETARY COMPANIONS (BARNARD'S STAR) ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Proposal Type 5. Continuation ID STELLAR ASTROPHYSICS GTO/AST 3 Long Term yrs 1005 Sub Category ------------------------------------------------------------------------------------ 6. Principal Investigator Institution Country Telephone Dr. William H. Jefferys UNIVERSITY OF TEXAS AT AUSTI USA (512) 471-1455 PROFESSOR ------------------------------------------------------------------------------------ 7. Abstract With these HST observations we are initiating a systematic search for variable proper motion objects trying to discover low mass objects in orbit around red dwarfs. Using well established astrometric techniques we will secure relative positional measurements for selected objects over very long intervals of time looking for systematic perturbations to rectilinear motion. Within the Astrometric Data Reduction System (SDAS), such perturbations will be extracted and reduced further to provide the relevant mass and orbital parameters of the composents. The HST is an instrument, the engineering specifications of which, open up the opportunity to extend this astrometric discipline far beyond the present bounds of ground-based and other observations. ------------------------------------------------------------------------------------ 8. Scientific Key Words: UNSEEN COMPANIONS, PLANETRAY COMPANIONS, BLACK DWARFS ------------------------------------------------------------------------------------ 9. Est obs time (hours) pri: 12.00 par: 0 10. Num targs pri: 1 par: 0 ------------------------------------------------------------------------------------ 11. Instruments requested: FGS ------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------ Page 2 I. GENERAL FORM Proposal 2938c PI: Dr. William H. Jefferys Proposal Title: UNSEEN AND PLANETARY COMPANIONS (BARNARD'S STAR) ------------------------------------------------------------------------------------ 1. Proposers: Proposers Institution Country ESA ------------------------------------------------------------------------------------ Dr. William H. Jefferys UNIVERSITY OF TEXAS USA Dr. George F. Benedict UNIVERSITY OF TEXAS USA Dr. Raynor L. Duncombe UNIVERSITY OF TEXAS USA Dr. Paul D. Hemenway UNIVERSITY OF TEXAS USA Dr. Peter S. Shelus UNIVERSITY OF TEXAS USA Dr. Otto G. Franz LOWELL OBSERVATORY USA Dr. Laurence W. Fredrick UNIVERSITY OF VIRGINIA USA Dr. William F. Van Altena YALE UNIVERSITY USA ------------------------------------------------------------------------------------ 2. Scientific Justification. Similar to Bessell's study of Sirius and Procyon, which led to the discovery of previously unseen stellar companions, observatories having access to long focus astrometric instruments have established very-long-term systematic searches for variable proper motion objects as a part of their standard parallax programs. These efforts have been rewarded by the discovery of objects of extreme astrophysical interest. The objects which have aroused the greatest excitement are those of very low mass in orbit around late spectral type stars. On an ordinary mass-luminosity diagram many of these objects lie below the lower mass limit presently hypothesized for actual stellar objects. If such objects are found in orbit about other stars and yet have masses so small that they cannot physically be stars, can they be planetary type objects? With the HST, an instrument having the engineering specifications that it does, there opens up a magnificent opportunity to continue a vital astrometric discipline in ways not previously possible. With the use of the Fine Guidance Sensors (FGS) we are planning a series of observations to establish a two-pronged effort for seeking deviations of motion from that which is rectilinear. The first of these concerns objects which are at or near the limits of ground-based techniques; with these we would wish to firmly confirm or reject the actual existence of perturbations and allow for a smooth transition between ground- and space-based observations of this type. The second would be an effort to search for objects which are now beyond ground-based technologies. Requested dates of observation fpr Barnard's Star are: 09/06/93, 09/21/93, 10/06/93, 03/06/94, 03/21/94, 04/05/94, 06/14/94, 06/29/94, 09/09/94, 09/21/94, 10/06/94, 03/06/95, 03/21/95, 04/05/95, 06/14/95, 06/29/95 09/09/95, 09/21/95, 10/06/95, ------------------------------------------------------------------------------------ 3. Description of proposed observations. These position mode observations are to be made within +/- 5 days of the listed dates. Observations are planned at times of both maximum and minimum parallax factors. At maximum parallax factor observations will be most sensitive to parallax; at minimum parallax factor observations will be most sensitive to proper motion. Observation sequence: Acquire guide stars in the FGS units selected got guiding. Measure target, then referenec stars, then target. Use FGS unit designated as Astrometry Prime. ------------------------------------------------------------------------------------ 4. Justification of need for HST observations. Ground-based parallaxes in the very best of circumstances are limited to 0.002 seconds of arc, which are some 4 times poorer than that projected for HST observations. Of much more importance is the fact that this four-fold increase from the best of the ground-based accuracies will enhance the chances fror detecting orbital perturbations undetectable from the ground. Page 3 ------------------------------------------------------------------------------------ 5. Description of special scheduling requirements. All observations must be made within +/- 5 days of listed dates. ------------------------------------------------------------------------------------ 6. Description of special calibration exposures. All of the FGS observations shoueld be uninterrupted to minimize effects of thermal drifts. ------------------------------------------------------------------------------------ 7. Data reduction and analysis plans. Data reduction will be performed using the ADRS within the SDAS system at STScI with other reductions being performed in Austin. All data will be put into the ADRS format for analysis using the GAUSS module. All results, together with best- level estimates of their errors and their covariances will be made available, as needed. ------------------------------------------------------------------------------------ 8. Additional comments or special requests. N/A ------------------------------------------------------------------------------------ 9. Description of previous HST work. N/A ------------------------------------------------------------------------------------ 10. Resources to be supplied by investigator's institution(s). ADRS will be available in Austin. ------------------------------------------------------------------------------------ 11. Address Information Name: JEFFERYS Category: PI Institution: Address: City: State: Zip Code: Country: Telephone: Telex (or e-mail): ------------------------------------------------------------------------------------ Name: WILLIAM H. JEFFERYS Category: PI Institution: UNIVERSITY OF TEXAS Address: DEPARTMENT OF ASTRONOMY City: AUSTIN State: TX Zip Code: 78712 Country: USA Telephone: (512)471-1455 Telex (or e-mail): TEXASTRO ------------------------------------------------------------------------------------ Name: PETER J. SHELUS Category: CON Institution: UNIVERSITY OF TEXAS Address: DEPARTMENT OF ASTRONOMY City: AUSTIN State: TX Zip Code: 78712 Country: USA Telephone: (512)471-3339 Telex (or e-mail): ------------------------------------------------------------------------------------ TARGET LIST a) Fixed Targets ID = 2938c [ 4] ------------------------------------------------------------------------------------------------------------------------------------ 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial |Acqui|FLX| Flux data No | Name | Description | Position |Eqnx | Vel. |Prblm|REF| | | | | | | | | ------------------------------------------------------------------------------------------------------------------------------------ 29 BARNARDS- HIGHEST PROPER MOTION RA = 17H 55M 20.94S +/- 2", 1950.0 1 V = 9.54 +/- 0.02 STAR STAR DEC = +4D 39' 21.40" +/- 2" Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) B 1985.50 -0.0500 +/- 0.0007 10.3100 +/- 0.0100 0.5520 +/- 0.0050 ------------------------------------------------------------------------------------------------------------------------------------ 30 BARNARD-75- REFERENCE STAR FOR RA = 269.436264D +/- 2000.0 1 V = 16.84 +/- 0.6 REF BARNARDS STAR 0.0003D, DEC = +4.690059D +/- 0.0003D ------------------------------------------------------------------------------------------------------------------------------------ 31 BARNARD-76- REFERENCE STAR FOR RA = 269.47687D +/- 0.0003D, 2000.0 1 V = 13.26 +/- 0.6 REF BARNARDS STAR DEC = +4.680570D +/- 0.0003D ------------------------------------------------------------------------------------------------------------------------------------ 32 BARNARD-77- REFERENCE STAR FOR RA = 269.478272D +/- 2000.0 1 V = 16.84 +/- 0.6 REF BARNARDS STAR 0.0003D, DEC = +4.677535D +/- 0.0003D ------------------------------------------------------------------------------------------------------------------------------------ 33 BARNARD-81- REFERENCE STAR FOR RA = 269.437087D +/- 2000.0 1 V = 15.5 +/- 0.6 REF BARNARDS STAR 0.0003D, DEC = +4.679343D +/- 0.0003D ------------------------------------------------------------------------------------------------------------------------------------ 34 BARNARD-90- REFERENCE STAR FOR RA = 269.42924D +/- 0.0003D, 2000.0 1 V = 15.5 +/- 0.6 REF BARNARDS STAR DEC = +4.666314D +/- 0.0003D ------------------------------------------------------------------------------------------------------------------------------------ 35 BARNARD-91- REFERENCE STAR FOR RA = 269.456590D +/- 2000.0 1 V = 14.52 +/- 0.6 REF BARNARDS STAR 0.0003D, DEC = +4.706910D +/- 0.0003D ------------------------------------------------------------------------------------------------------------------------------------ 36 BARNARD-93- REFERENCE STAR FOR RA = 269.457916D +/- 2000.0 1 V = 16.54 +/- 0.6 REF BARNARDS STAR 0.0003D, DEC = +4.674444D +/- 0.0003D ------------------------------------------------------------------------------------------------------------------------------------ 37 BARNARD-94- REFERENCE STAR FOR RA = 269.466480D +/- 2000.0 1 V = 11.18 +/- 0.6 REF BARNARDS STAR 0.0003D, DEC = +4.705630D +/- 0.0003D ------------------------------------------------------------------------------------------------------------------------------------ 38 BARNARD-110- REFERENCE STAR FOR RA = 269.427218D +/- 2000.0 1 V = 15.64 +/- 0.6 REF BARNARDS STAR 0.0003D, DEC = +4.646727D +/- 0.0003D ------------------------------------------------------------------------------------------------------------------------------------ EXPOSURE LOGSHEET ID = 2938c [ 5] ------------------------------------------------------------------------------------------------------------------------------------ 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 |10 | 11 | 12 |13 |14| 15 ------------------------------------------------------------------------------------------------------------------------------------ Line | Seq | Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | S/N |Flx|Pr| Special Number | Name | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| |Rel. Time|Ref| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 20 DEFINE BARNARDS- FGS POS PRIME F583W DATA-RATE=32 1 52S 10 1 1 SEQ 20-22 NON-INT SEQ21 STAR GUID TOL 0.007" GROUP-FGS 20-22 WITHIN 30M Comments: AVOID TERMINATOR CROSSING IF THE VISIBILITY PERIOD IS LESS THAN 30M, PLEASE CONTACT PETE SHELUS. IF IT IS MORE THAN 30M, THEN GROUP-FGS CAN BE TAILORED TO FIT. ------------------------------------------------------------------------------------------------------------------------------------ 21 DEFINE BARNARD-75- ^ ^ ^ ^ ^ ^ ^ ^ ^ DO FOR TARG 30-38 SEQ21 REF Comments: OBSERVE ONLY THOSE REFERENCE STARS WITHIN THE ASTROMETRY PICKLE ------------------------------------------------------------------------------------------------------------------------------------ 22 DEFINE BARNARDS- ^ ^ ^ ^ ^ ^ ^ ^ ^ SEQ21 STAR ------------------------------------------------------------------------------------------------------------------------------------ 23 USE AT 06-SEP-93 +/- SEQ21 5D REPEAT 23 EVERY 15D +/- 1D FOR 2 MORE TIMES Comments: MAXIMUM NEGATIVE PARALLAX CYCLE 3 FACTOR ------------------------------------------------------------------------------------------------------------------------------------ 24 USE AT 06-MAR-94 +/- SEQ21 5D REPEAT 24 EVERY 15D +/- 1D FOR 2 MORE TIMES Comments: MAXIMUM POSITIVE PARALLAX CYCLE 3 FACTOR ------------------------------------------------------------------------------------------------------------------------------------ 25 USE AT 14-JUN-94 +/- SEQ21 5D REPEAT 25 EVERY 15D +/- 1D FOR 1 MORE TIMES Comments: ZERO PARALLAX FACTOR CYCLE 3 ------------------------------------------------------------------------------------------------------------------------------------ EXPOSURE LOGSHEET ID = 2938c [ 6] ------------------------------------------------------------------------------------------------------------------------------------ 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 |10 | 11 | 12 |13 |14| 15 ------------------------------------------------------------------------------------------------------------------------------------ Line | Seq | Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | S/N |Flx|Pr| Special Number | Name | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| |Rel. Time|Ref| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 26 USE AT 06-SEP-94 +/- SEQ21 5D REPEAT 26 EVERY 15D +/- 1D FOR 2 MORE TIMES Comments: MAXIMUM NEGATIVE PARALLAX CYCLE 3 FACTOR ------------------------------------------------------------------------------------------------------------------------------------ 27 USE AT 06-MAR-95 +/- SEQ21 5D REPEAT 27 EVERY 15D +/- 1D FOR 2 MORE TIMES Comments: MAXIMUM POSITIVE PARALLAX CYCLE 3 FACTOR ------------------------------------------------------------------------------------------------------------------------------------ 28 USE AT 14-JUN-95 +/- SEQ21 5D REPEAT 28 EVERY 15D +/- 1D FOR 1 MORE TIMES Comments: ZERO PARALLAX FACTOR CYCLE 3 ------------------------------------------------------------------------------------------------------------------------------------ 29 USE AT 06-SEP-95 +/- SEQ21 5D REPEAT 29 EVERY 15D +/- 1D FOR 2 MORE TIMES Comments: MAXIMUM NEGATIVE PARALLAX CYCLE 3 FACTOR ------------------------------------------------------------------------------------------------------------------------------------ Summary Form for Proposal 2938c [ 7] Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations FGS ^ ------------------------------------------------------------------------------------------------------------------------------------ Opmodes POS ^ ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters DATA-RATE=32 ------------------------------------------------------------------------------------------------------------------------------------ Proposal for GTO/AST ------------------------------------------------------------------------------------------------------------------------------------ S/C Hours 12.00 ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category STELLAR ASTROPHYSICS ------------------------------------------------------------------------------------------------------------------------------------ Scientific Sub-category ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements SEQ 20-22 NON-INT; GUID TOL 0.007"; GROUP-FGS 20-22 WITHIN 30M; DO FOR TARG 30-38; AT 06-SEP-93 +/- 5D; REPEAT 23 EVERY 15D +/- 1D FOR 2 MORE TIMES; CYCLE 3; AT 06-MAR-94 +/- 5D; REPEAT 24 EVERY 15D +/- 1D FOR 2 MORE AT 14-JUN-94 +/- 5D; REPEAT 25 EVERY 15D +/- 1D FOR 1 MORE AT 06-SEP-94 +/- 5D; REPEAT 26 EVERY 15D +/- 1D FOR 2 MORE AT 06-MAR-95 +/- 5D; REPEAT 27 EVERY 15D +/- 1D FOR 2 MORE AT 14-JUN-95 +/- 5D; REPEAT 28 EVERY 15D +/- 1D FOR 1 MORE AT 06-SEP-95 +/- 5D; REPEAT 29 EVERY 15D +/- 1D FOR 2 MORE ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F583W ^ ------------------------------------------------------------------------------------------------------------------------------------ Target Names BARNARDS-STAR BARNARD-75-REF BARNARD-76-REF BARNARD-77-REF BARNARD-81-REF BARNARD-90-REF BARNARD-91-REF BARNARD-93-REF BARNARD-94-REF BARNARD-110-REF ------------------------------------------------------------------------------------------------------------------------------------