Page 1 PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID 5711 Report Date: 18-Jul-95:17:53 Version: ********** Check-in Date: ********** 1.Proposal Title: BLACK HOLE BINARIES IN THE LMC ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Proposal Type 5. Continuation ID STELLAR ASTROPHYSICS GO/CAR 3489 Sub Category X-RAY BINARIES ------------------------------------------------------------------------------------ 6. Principal Investigator Institution Country Telephone John B Hutchings DOMINION ASTROPHYSICAL OBSER CANADA 604-363-0018 ------------------------------------------------------------------------------------ 7. Abstract The endpoints of stellar evolution - white dwarfs, neutron stars and black holes - can be most directly studied when they occur in binary systems such as cataclysmic variables and X-ray binaries. However, only a handful of black-hole candidates have been found, and thus very little is known about their physical properties and associated accretion disks. Two black-hole X-ray binaries, LMC X-3 and CAL 87, are particularly suitable for investigation in the UV, where important diagnostic emission lines are present and where the disk structure can be modelled from the continuum. LMC X-3 has recently been found to have a precessing accretion disk (P = 200 days) allowing different parts of the disk to be observed over a timescale of months. CAL 87 (P orb 10.6hr) is the only known eclipsing black hole, so that observation throughout the eclipse will yield detailed information about the disk structure, particularly very near the collapsed star itself. ------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------ 9. Est obs time (hours) pri: 13.30 par: 0.70 10. Num targs pri: 2 par: 2 ------------------------------------------------------------------------------------ 11. Instruments requested: HRS FOS WF/PC ------------------------------------------------------------------------------------ 12. Special sched req: Time Critical obs. ------------------------------------------------------------------------------------ Page 2 I. GENERAL FORM Proposal 5711 PI: John B Hutchings Proposal Title: BLACK HOLE BINARIES IN THE LMC ------------------------------------------------------------------------------------ 1. Proposers: Proposers Institution Country ESA ------------------------------------------------------------------------------------ Pi John B Hutchings DOMINION ASTROPHYSICAL CANADA OBSERVATORY Anne P Cowley ARIZONA STATE UNIVERSITY USA David Crampton DOMINION ASTROPHYSICAL CANADA OBSERVATORY Paul C Schmidke ARIZONA STATE UNIVERSITY USA ------------------------------------------------------------------------------------ 3. Description of proposed observations. For LMC X-3 we propose to obtain low dispersion GHRS spectra at two wavelength settings, to cover 1160-1750A at each observation. As the star is faint (17.5m), we will need to acquire by blind offset from a nearby brighter star, unless HST pointing improves. The observation will be repeated at five 200-day (disk precession) phases, at a fixed (1.7-day) orbital phase. If GHRS low dispersion observations are not possible, we would use the FOS with G130H and G190H gratings to cover the same spectral range. For FOS use, the target acquisition will be direct. For CAL 87, we propose to obtain FOS low dispersion (G160L) spectra at 6 binary phases, to model the continuum changes through the 10 hour orbit. We also propose to obtain FOS high dispersion (G130H) spectra of the C IV line at 3 binary phases, to measure the profile changes, and model the eclipse of the line- emitting region. We request parallel exposures with the PC to study the stellar population of the LMC in the neighbourhood of these binaries. ------------------------------------------------------------------------------------ 4. Justification of need for HST observations. For LMC X-3, we require minimum S/N of 20 per 2A (LSA resolution) with GHRS, and this leads to exposure estimates of 2 hours for the combined 2 grating settings, for each visit to the star. (This is true for observation with either GHRS or FOS, as throughput and efficiencies trade off roughly.) The UV flux of CAL 87 is not known (but will be after the cycle 1 GTO data are obtained). Best estimates require 10 minutes for the FOS low dispersion spectra to achieve a mean S/N of 10 over the UV continuum. The Si IV and C IV line data require a S/N of 20 per ~2A (1 arcsec aperture resolution) and we estimate exposures for this grating setting of 30 mins per visit. To sample the periods sufficiently, we require 5 or more visits to each system, making a total of ~14 hours integration time. ------------------------------------------------------------------------------------ 5. Description of special scheduling requirements. The proposal requires observations at specific binary and precession phases to accomplish its science goals. We will specify windows of these phases as widely as possible, to facilitate scheduling, but the timing is an essential requirement. ------------------------------------------------------------------------------------ 11. Address Information Name: JOHN B HUTCHINGS Category: PI Institution: DOMINION ASTROPHYSICAL OBSERVATOR Address: 5071 W. SAANICH RD City: VICTORIA State: BC Zip Code: V8X 4M6 Country: CANADA Telephone: 604-363-0018 Telex (or e-mail): 049-7295 NRC DAO VIC ------------------------------------------------------------------------------------ TARGET LIST a) Fixed Targets ID = 5711 [ 3] ------------------------------------------------------------------------------------------------------------------------------------ 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| | | | | | | | | ------------------------------------------------------------------------------------------------------------------------------------ 1 CAL87STAR A, 139 PLATE-ID=05ZW, 2000 1 V=12.3,TYPE=K0 RA=5H 46M 50.3S+/-1", DEC=-71D 10' 17.70"+/-1" ------------------------------------------------------------------------------------------------------------------------------------ 2 OFFSET-CAL87 A, 133 RA-OFF=-3.47S+/- 0.1S, 2000 1 V=19.0 +/- 0.4,TYPE=F DEC-OFF=82.6" +/- 0.3", FROM 1, PLATE-ID=05ZW Comments: UV FLUXES KNOWN FROM IUE. ------------------------------------------------------------------------------------------------------------------------------------ TARGET LIST c)Generic Targets ID = 5711 [ 4] ------------------------------------------------------------------------------------------------------------------------------------ 1 | 2 | 3 | 4 | 5 | 7 ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Selection Criteria |Acqui|FLX| Flux data No | Name | Description | |Prblm|REF| | | | | | | ------------------------------------------------------------------------------------------------------------------------------------ 3 FIELD-NEAR- LMC FIELD WFPC2 PARALLEL OBSERVATION CAL87 ------------------------------------------------------------------------------------------------------------------------------------ EXPOSURE LOGSHEET ID = 5711 [ 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 ------------------------------------------------------------------------------------------------------------------------------------ 30 CAL87STAR FOS/BL ACQ/ 4.3 MIRROR 1 3S 1 ONBOARD ACQ FOR BINARY 30.1 CYCLE 4 / 30-34 SEQ 30-32.1 NO GAP ------------------------------------------------------------------------------------------------------------------------------------ 30.1 CAL87STAR FOS/BL ACQ/ 0.3 MIRROR SCAN-STEP-X=0.1 1 3S 1 ONBOARD ACQ FOR PEAK SCAN-STEP-Y=0.1 30.5 SEARCH-SIZE-X=4 SEARCH-SIZE-Y=4 ------------------------------------------------------------------------------------------------------------------------------------ 30.5 OFFSET- FOS/BL ACQ/ 0.5 MIRROR SCAN-STEP-X=0.3 1 30S 1 ONBOARD ACQ FOR 31 CAL87 PEAK SCAN-STEP-Y=0.3 -32.1 SEARCH-SIZE-X=3 SEARCH-SIZE-Y=3 ------------------------------------------------------------------------------------------------------------------------------------ 31 OFFSET- FOS/BL ACCUM 1.0 G160L 1150- 1 30M 1 ZERO-PHASE CAL87 2510 JD2447506.80 +/- 0.02D PERIOD 0.44268D +/- 0.00001D PHASE 0.6 +/- 0.06 ------------------------------------------------------------------------------------------------------------------------------------ 32 OFFSET- FOS/BL ACCUM 1.0 G160L 1150- 6 38M 1 CAL87 2510 ------------------------------------------------------------------------------------------------------------------------------------ 32.1 OFFSET- FOS/BL ACCUM 1.0 G160L 1150- 1 30M 1 CAL87 2510 ------------------------------------------------------------------------------------------------------------------------------------ 33 FIELD-NEAR- WFPC2 IMAGE WFALL F469N 1 9320S 1 PAR CAL87 Comments: INTENDED TO BE PARALLEL WITH 32 ------------------------------------------------------------------------------------------------------------------------------------ 34 FIELD-NEAR- WFPC2 IMAGE WFALL F467M CR-SPLIT=NO 1 1700S 1 PAR CAL87 Comments: INTENDED TO BE PARALLEL WITH 31 ------------------------------------------------------------------------------------------------------------------------------------ Summary Form for Proposal 5711 [ 6] Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations FOS/BL WFPC2 ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACQ/BINARY ACQ/PEAK ACCUM IMAGE ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters SCAN-STEP-X=0.1 SCAN-STEP-Y=0.1 SEARCH-SIZE-X=4 SEARCH-SIZE-Y=4 SCAN-STEP-X=0.3 SCAN-STEP-Y=0.3 SEARCH-SIZE-X=3 SEARCH-SIZE-Y=3 CR-SPLIT=NO ------------------------------------------------------------------------------------------------------------------------------------ Proposal for GO/CAR ------------------------------------------------------------------------------------------------------------------------------------ S/C Hours 13.30 ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category STELLAR ASTROPHYSICS ------------------------------------------------------------------------------------------------------------------------------------ Scientific Sub-category X-RAY BINARIES ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ONBOARD ACQ FOR 30.1; CYCLE 4 / 30-34; SEQ 30-32.1 NO GAP; ONBOARD ACQ FOR 30.5; ONBOARD ACQ FOR 31-32.1; ZERO-PHASE JD2447506.80 +/- 0.02D; PERIOD 0.44268D +/- 0.00001D; PHASE 0.6 +/- 0.06 PAR ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements MIRROR G160L F469N F467M ------------------------------------------------------------------------------------------------------------------------------------ Target Names CAL87STAR OFFSET-CAL87 FIELD-NEAR-CAL87 ------------------------------------------------------------------------------------------------------------------------------------