7306( 2) - 02/28/97 18:19 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 7306 Version: 2 Check-in Date: 28-Feb-1997 17:16:22 1.Proposal Title: Halo Microlens Source Systems and their Underlying Stellar Backgrounds ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Cycle STELLAR POPULATIONS GO 7 ------------------------------------------------------------------------------------ 5. Investigators Contact? PI: Kem Cook Lawrence Livermore National Laboratory CoI: Dave Bennett University of Notre Dame N CoI: Will Sutherland Oxford N CoI: Ken Freeman Mt. Stromlo and Siding Spring N Observatories CoI: Charles Alcock Lawrence Livermore National Laboratory N CoI: Robyn Allsman Australian National University N CoI: Kim Griest U.C. San Diego N CoI: Tim Axelrod Mt. Stromlo and Siding Spring N Observatories CoI: Dante Minniti Lawrence Livermore National Laboratory Y CoI: Stuart Marshall Lawrence Livermore National Laboratory N CoI: Bruce Peterson Mt. Stromlo and Siding Spring N Observatories CoI: Peter Quinn European Southern Observatory N CoI: Alex Rodgers Mt. Stromlo and Siding Spring N Observatories CoI: Chris Stubbs University of Washington N CoI: Doug Welch McMaster University N ------------------------------------------------------------------------------------ 6. Abstract The MACHO project has recently analyzed 2 years of LMC data, revealing 8 candidate microlensing events, and suggesting the existence of dark objects in the galactic halo. We propose to obtain medium-deep broadband images of 7 source stars for these events plus one additional star. This will allow us to determine a) which star was actually lensed, b) the amount of crowding in our ground-based frames, c) if the stars are normal in the CMD, and d) if they lie preferentially at the back of the LMC. This provides a clear test for microlensing by halo objects. ------------------------------------------------------------------------------------ 7306( 2) - 02/28/97 18:19 - [ 2] Observations Description ------------------------ We propose to image 8 fields in the LMC in order to determine the luminosity function, individual reddenings and the stellar types to about V=24.5 which is 3.5 magnitudes deeper than the Macho Project photometry. The observations will consist of 8 visits of 3 orbits to obtain observations of the source stars for microlensing events. This will allow us to assess the effects of the underlying stellar populations on our microlensing measurements. The spatial resolution of HST is required to resolve the source stars from nearby companions and allow accurate color determination as well as provide better template information for re-reducing the ground based photometry of the events. We will also gain knowledge of their position in th LMC and possible confusion with other sources such as a luminous lenses. We will obtain two color information in filters most closely matched to the Macho passbands, F555W and F675W, allowing us to determine deep luminosity functions for detection efficiency corrections. In addition, we will obtain data in F439W and F814W to most efficiently get color- color information on the microlensing sources. With these observations we will determine the probability of confusion caused color-color irregularities and compare this with the determined colors of the microlensing sources. We are not asking for CVZ observations because these objects are in the wings of the southern CVZ zone and past experience has shown this area hard to schedule as CVZ. The exposures necessary for this project consist of 1 x 20 second sets of F555W, F675W, F814W, and F439W exposures to tie to our ground based photometry (these tie frames do not need to be CR split) and 3 x 400 second sets of exposures in the F555W, F675W and F814W which will yield better than 5\\ require 2 orbits per star and allow VRI color-color discrimination at the 1 We will also obtain 4 x 600 seconds of F439W which will yield 1\\ photometry to V = 21 for 2\\ stars. The F439W observations will take an additional orbit per visit. For these calculations, we have used the WFPC2 ETC and assumed 22 mag per square arcsec background from the LMC. We will request dithering for optimum co-addition. The source will be placed on the PC for maximum spatial resolution, but the WF chips will provide useful information for the luminosity function measurements. Real Time Justification ----------------------- Describe continued macho observations?? Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ Data Distribution Media: ELECTRONIC Blocking Factor: 10 Ship To: PI_Address Ship Via: Email: ------------------------------------------------------------------------------------ 7306( 2) - 02/28/97 18:19 - [ 3] TARGET LIST a) Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 STAR-0517- EXT-STAR RA=05H 17M 14.6S +/-1S, DEC=-70D 2000 V=230 V = 20.0 7047 46' 59" +/- 1" B-V = 0.4 Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 2000 0.00 0.00 0.00 2 STAR-0517- EXT-STAR RA=05H 16M 41.1S +/-1S, DEC=-70D 2000 V=230 V = 20.7 7029 29' 18" +/- 1" B-V = 1.0 Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 2000 0.00 0.00 0.00 3 STAR-0526- EXT-STAR RA=05H 26M 14.0S +/-1S, DEC=-70D 2000 V=230 V = 19.6 7021 21' 15" +/- 1" B-V = 0.6 Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 2000 0.00 0.00 0.00 4 STAR-0504- EXT-STAR RA=05H 04M 03.4S +/-1S, DEC=-69D 2000 V=230 V = 20.7 6933 33' 19" +/- 1" B-V = 0.8 Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 2000 0.00 0.00 0.00 5 STAR-0525- EXT-STAR RA=05H 25M 09.4S +/-1S, DEC=-69D 2000 V=230 V = 20.1 6948 47' 54" +/- 1" B-V = 0.6 Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 2000 0.00 0.00 0.00 6 STAR-0520- EXT-STAR RA=05H 20M 20.3S +/-1S, DEC=-69D 2000 V=230 V = 19.3 6915 15' 12" +/- 1" B-V = 0.6 Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 2000 0.00 0.00 0.00 7 STAR-0501- EXT-STAR RA=05H 01M 16.0S +/-1S, DEC=-69D 2000 V=230 V = 19.4 6908 07' 33" +/- 1" B-V = 0.4 Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 2000 0.00 0.00 0.00 8 STAR-0534- EXT-STAR RA=05H 33M 51.7S +/-1S, DEC=-70D 2000 V=230 V = 21.5 7051 50' 59" +/- 1" B-V = 0.6 Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 2000 0.00 0.00 0.00 7306( 2) - 02/28/97 18:19 - [ 4] Visit: 01 Visit Requirements: 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 STAR-0517-7 WFPC2 IMAGE PC1 F439W DITHER-TYPE=BOX 1 400 S 047 ------------------------------------------------------------------------------------------------------------------------------------ 2 STAR-0517-7 WFPC2 IMAGE PC1 F439W 1 20 S 047 ------------------------------------------------------------------------------------------------------------------------------------ 3 STAR-0517-7 WFPC2 IMAGE PC1 F675W 1 20 S 047 ------------------------------------------------------------------------------------------------------------------------------------ 4 STAR-0517-7 WFPC2 IMAGE PC1 F675W DITHER-TYPE=LINE 1 400 S 047 ------------------------------------------------------------------------------------------------------------------------------------ 5 STAR-0517-7 WFPC2 IMAGE PC1 F814W DITHER-TYPE=LINE 1 500 S 047 ------------------------------------------------------------------------------------------------------------------------------------ 6 STAR-0517-7 WFPC2 IMAGE PC1 F814W 2 20 S 047 ------------------------------------------------------------------------------------------------------------------------------------ 7 STAR-0517-7 WFPC2 IMAGE PC1 F555W DITHER-TYPE=BOX 1 400 S 047 ------------------------------------------------------------------------------------------------------------------------------------ 8 STAR-0517-7 WFPC2 IMAGE PC1 F555W 1 20 S 047 ------------------------------------------------------------------------------------------------------------------------------------ 7306( 2) - 02/28/97 18:19 - [ 5] Visit: 02 Visit Requirements: 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 STAR-0517-7 WFPC2 IMAGE PC1 F439W DITHER-TYPE=BOX 1 400 S 029 ------------------------------------------------------------------------------------------------------------------------------------ 2 STAR-0517-7 WFPC2 IMAGE PC1 F439W 1 20 S 029 ------------------------------------------------------------------------------------------------------------------------------------ 3 STAR-0517-7 WFPC2 IMAGE PC1 F675W 1 20 S 029 ------------------------------------------------------------------------------------------------------------------------------------ 4 STAR-0517-7 WFPC2 IMAGE PC1 F675W DITHER-TYPE=LINE 1 400 S 029 ------------------------------------------------------------------------------------------------------------------------------------ 5 STAR-0517-7 WFPC2 IMAGE PC1 F814W DITHER-TYPE=LINE 1 500 S 029 ------------------------------------------------------------------------------------------------------------------------------------ 6 STAR-0517-7 WFPC2 IMAGE PC1 F814W 2 20 S 029 ------------------------------------------------------------------------------------------------------------------------------------ 7 STAR-0517-7 WFPC2 IMAGE PC1 F555W DITHER-TYPE=BOX 1 400 S 029 ------------------------------------------------------------------------------------------------------------------------------------ 8 STAR-0517-7 WFPC2 IMAGE PC1 F555W 1 20 S 029 ------------------------------------------------------------------------------------------------------------------------------------ 7306( 2) - 02/28/97 18:19 - [ 6] Visit: 03 Visit Requirements: 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 STAR-0526-7 WFPC2 IMAGE PC1 F439W DITHER-TYPE=BOX 1 400 S 021 ------------------------------------------------------------------------------------------------------------------------------------ 2 STAR-0526-7 WFPC2 IMAGE PC1 F439W 1 20 S 021 ------------------------------------------------------------------------------------------------------------------------------------ 3 STAR-0526-7 WFPC2 IMAGE PC1 F675W 1 20 S 021 ------------------------------------------------------------------------------------------------------------------------------------ 4 STAR-0526-7 WFPC2 IMAGE PC1 F675W DITHER-TYPE=LINE 1 400 S 021 ------------------------------------------------------------------------------------------------------------------------------------ 5 STAR-0526-7 WFPC2 IMAGE PC1 F814W DITHER-TYPE=LINE 1 500 S 021 ------------------------------------------------------------------------------------------------------------------------------------ 6 STAR-0526-7 WFPC2 IMAGE PC1 F814W 2 20 S 021 ------------------------------------------------------------------------------------------------------------------------------------ 7 STAR-0526-7 WFPC2 IMAGE PC1 F555W DITHER-TYPE=BOX 1 400 S 021 ------------------------------------------------------------------------------------------------------------------------------------ 8 STAR-0526-7 WFPC2 IMAGE PC1 F555W 1 20 S 021 ------------------------------------------------------------------------------------------------------------------------------------ 7306( 2) - 02/28/97 18:19 - [ 7] Visit: 04 Visit Requirements: 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 STAR-0504-6 WFPC2 IMAGE PC1 F439W DITHER-TYPE=BOX 1 400 S 933 ------------------------------------------------------------------------------------------------------------------------------------ 2 STAR-0504-6 WFPC2 IMAGE PC1 F675W 1 20 S 933 ------------------------------------------------------------------------------------------------------------------------------------ 3 STAR-0504-6 WFPC2 IMAGE PC1 F675W DITHER-TYPE=LINE 1 400 S 933 ------------------------------------------------------------------------------------------------------------------------------------ 4 STAR-0504-6 WFPC2 IMAGE PC1 F814W DITHER-TYPE=LINE 1 500 S 933 ------------------------------------------------------------------------------------------------------------------------------------ 5 STAR-0504-6 WFPC2 IMAGE PC1 F814W 1 20 S 933 ------------------------------------------------------------------------------------------------------------------------------------ 6 STAR-0504-6 WFPC2 IMAGE PC1 F555W DITHER-TYPE=BOX 1 400 S 933 ------------------------------------------------------------------------------------------------------------------------------------ 7 STAR-0504-6 WFPC2 IMAGE PC1 F555W 1 20 S 933 ------------------------------------------------------------------------------------------------------------------------------------ 7306( 2) - 02/28/97 18:19 - [ 8] Visit: 05 Visit Requirements: 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 STAR-0525-6 WFPC2 IMAGE PC1 F439W DITHER-TYPE=BOX 1 400 S 948 ------------------------------------------------------------------------------------------------------------------------------------ 2 STAR-0525-6 WFPC2 IMAGE PC1 F675W 1 20 S 948 ------------------------------------------------------------------------------------------------------------------------------------ 3 STAR-0525-6 WFPC2 IMAGE PC1 F675W DITHER-TYPE=LINE 1 400 S 948 ------------------------------------------------------------------------------------------------------------------------------------ 4 STAR-0525-6 WFPC2 IMAGE PC1 F814W DITHER-TYPE=LINE 1 500 S 948 ------------------------------------------------------------------------------------------------------------------------------------ 5 STAR-0525-6 WFPC2 IMAGE PC1 F814W 1 20 S 948 ------------------------------------------------------------------------------------------------------------------------------------ 6 STAR-0525-6 WFPC2 IMAGE PC1 F555W DITHER-TYPE=BOX 1 400 S 948 ------------------------------------------------------------------------------------------------------------------------------------ 7 STAR-0525-6 WFPC2 IMAGE PC1 F555W 1 20 S 948 ------------------------------------------------------------------------------------------------------------------------------------ 7306( 2) - 02/28/97 18:19 - [ 9] Visit: 06 Visit Requirements: 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 STAR-0520-6 WFPC2 IMAGE PC1 F439W DITHER-TYPE=BOX 1 400 S 915 ------------------------------------------------------------------------------------------------------------------------------------ 2 STAR-0520-6 WFPC2 IMAGE PC1 F675W 1 20 S 915 ------------------------------------------------------------------------------------------------------------------------------------ 3 STAR-0520-6 WFPC2 IMAGE PC1 F675W DITHER-TYPE=LINE 1 400 S 915 ------------------------------------------------------------------------------------------------------------------------------------ 4 STAR-0520-6 WFPC2 IMAGE PC1 F814W DITHER-TYPE=LINE 1 500 S 915 ------------------------------------------------------------------------------------------------------------------------------------ 5 STAR-0520-6 WFPC2 IMAGE PC1 F814W 1 20 S 915 ------------------------------------------------------------------------------------------------------------------------------------ 6 STAR-0520-6 WFPC2 IMAGE PC1 F555W DITHER-TYPE=BOX 1 400 S 915 ------------------------------------------------------------------------------------------------------------------------------------ 7 STAR-0520-6 WFPC2 IMAGE PC1 F555W 1 20 S 915 ------------------------------------------------------------------------------------------------------------------------------------ 7306( 2) - 02/28/97 18:19 - [ 10] Visit: 07 Visit Requirements: 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 STAR-0501-6 WFPC2 IMAGE PC1 F439W DITHER-TYPE=BOX 1 400 S 908 ------------------------------------------------------------------------------------------------------------------------------------ 2 STAR-0501-6 WFPC2 IMAGE PC1 F675W 1 20 S 908 ------------------------------------------------------------------------------------------------------------------------------------ 3 STAR-0501-6 WFPC2 IMAGE PC1 F675W DITHER-TYPE=LINE 1 400 S 908 ------------------------------------------------------------------------------------------------------------------------------------ 4 STAR-0501-6 WFPC2 IMAGE PC1 F814W DITHER-TYPE=LINE 1 500 S 908 ------------------------------------------------------------------------------------------------------------------------------------ 5 STAR-0501-6 WFPC2 IMAGE PC1 F814W 1 20 S 908 ------------------------------------------------------------------------------------------------------------------------------------ 6 STAR-0501-6 WFPC2 IMAGE PC1 F555W DITHER-TYPE=BOX 1 400 S 908 ------------------------------------------------------------------------------------------------------------------------------------ 7 STAR-0501-6 WFPC2 IMAGE PC1 F555W 1 20 S 908 ------------------------------------------------------------------------------------------------------------------------------------ 7306( 2) - 02/28/97 18:19 - [ 11] Visit: 08 Visit Requirements: 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 ------------------------------------------------------------------------------------------------------------------------------------ 1 STAR-0534-7 WFPC2 IMAGE PC1 F439W DITHER-TYPE=BOX 1 400 S 051 ------------------------------------------------------------------------------------------------------------------------------------ 2 STAR-0534-7 WFPC2 IMAGE PC1 F439W 1 20 S 051 ------------------------------------------------------------------------------------------------------------------------------------ 3 STAR-0534-7 WFPC2 IMAGE PC1 F675W 1 20 S 051 ------------------------------------------------------------------------------------------------------------------------------------ 4 STAR-0534-7 WFPC2 IMAGE PC1 F675W DITHER-TYPE=LINE 1 400 S 051 ------------------------------------------------------------------------------------------------------------------------------------ 5 STAR-0534-7 WFPC2 IMAGE PC1 F814W DITHER-TYPE=LINE 1 500 S 051 ------------------------------------------------------------------------------------------------------------------------------------ 6 STAR-0534-7 WFPC2 IMAGE PC1 F814W 2 20 S 051 ------------------------------------------------------------------------------------------------------------------------------------ 7 STAR-0534-7 WFPC2 IMAGE PC1 F555W DITHER-TYPE=BOX 1 400 S 051 ------------------------------------------------------------------------------------------------------------------------------------ 8 STAR-0534-7 WFPC2 IMAGE PC1 F555W 1 20 S 051 ------------------------------------------------------------------------------------------------------------------------------------ 7306( 2) - 02/28/97 18:19 - [ 12] Summary Form for Proposal 7306 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFPC2 ------------------------------------------------------------------------------------------------------------------------------------ Opmodes IMAGE ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters DITHER-TYPE=BOX DITHER-TYPE=LINE ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category STELLAR POPULATIONS ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F439W F675W F814W F555W ------------------------------------------------------------------------------------------------------------------------------------ Target Names STAR-0517-7047 STAR-0517-7029 STAR-0526-7021 STAR-0504-6933 STAR-0525-6948 STAR-0520-6915 STAR-0501-6908 STAR-0534-7051 ------------------------------------------------------------------------------------------------------------------------------------