8676( 2) - 05/08/00 16:48 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 8676 Version: 2 Check-in Date: 06-Mar-2000 09:10:05 1.Proposal Title: Halo Microlens Source Systems and their Backgrounds and Reddening ------------------------------------------------------------------------------------ 2. Proposal For 3. Cycle GO 9 ------------------------------------------------------------------------------------ 4. Investigators Contact? PI: Kem Cook Lawrence Livermore National Laboratory CoI: Cailin Nelson Lawrence Livermore National Laboratory N CoI: Dr. Piotr Popowski Lawrence Livermore National Laboratory N CoI: Dr. Charles Alcock Lawrence Livermore National Laboratory N ------------------------------------------------------------------------------------ 5. Abstract The MACHO project is about to release 5.7 years of LMC data revealing ~ 20 candidate microlensing events, and suggesting the existence of dark objects in the Galactic halo. We propose to obtain medium-deep broadband images of 8 of the new candidate source stars. 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. ------------------------------------------------------------------------------------ 8676( 2) - 05/08/00 16:48 - [ 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 ----------------------- Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ 8676( 2) - 05/08/00 16:48 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 STAR-0502- STAR, G III-I RA=05H 2M 16S +/- 1", DEC=-68D J2000 V = 19.112+/-0.5 6801 0' 52" +/- 1" V-R = 0.534 Coordinate Source: OTHER_SOURCE 2 STAR-0506- STAR, F3-F9 RA=05H 5M 46S +/- 1", DEC=-69D J2000 V = 21.351 6944 43' 51" +/- 1" V-R = 0.091 Coordinate Source: OTHER_SOURCE 3 STAR-0545- STAR, A4-A9 V-IV RA=05H 45M 21S +/- 1", DEC=-71D J2000 V = 19.580 7109 9' 12" +/- 1" V-R = 0.271 Coordinate Source: OTHER_SOURCE 4 STAR-0457- STAR, A4-A9 V-IV RA=04H 57M 14S +/- 1", DEC=-69D J2000 V = 20.142 6928 27' 48" +/- 1" V-R = 0.042 Coordinate Source: OTHER_SOURCE 5 STAR-0506- STAR, A4-A9 V-IV RA=05H 6M 17S +/- 1", DEC=-70D J2000 V = 20.311 7059 58' 47" +/- 1" V-R = 0.305 Coordinate Source: OTHER_SOURCE 6 STAR-0524- STAR, G V-IV RA=05H 24M 3S +/- 1", DEC=-68D J2000 V = 22.8 6849 49' 12" +/- 1" V-R = 0.393 Coordinate Source: OTHER_SOURCE 7 STAR-0454- STAR, F3-F9 RA=04H 54M 19S +/- 1", DEC=-70D J2000 V = 22.037 7002 2' 19" +/- 1" V-R = 0.295 Coordinate Source: OTHER_SOURCE 8 STAR-0506- STAR, K V-IV RA=05H 6M 35S +/- 1", DEC=-69D J2000 V = 25.946 6920 20' 48" +/- 1" V-R = 0.343 Coordinate Source: OTHER_SOURCE 8676( 2) - 05/08/00 16:48 - [ 4] Patterns ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 1 Primary_Pattern Secondary_Pattern Pattern_Type WFPC2-LINE Pattern_Purpose DITHER Number_Of_Points 3 Point_Spacing 0.3535 Coordinate_Frame POS-TARG Pattern_Orient 45 Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 2 Primary_Pattern Secondary_Pattern Pattern_Type WFPC2-LINE Pattern_Purpose DITHER Number_Of_Points 2 Point_Spacing 0.3535 Coordinate_Frame POS-TARG Pattern_Orient 45 Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 3 Primary_Pattern Secondary_Pattern Pattern_Type WFPC2-LINE Pattern_Purpose DITHER Number_Of_Points 5 Point_Spacing 0.3535 Coordinate_Frame POS-TARG Pattern_Orient 45 Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 4 Primary_Pattern Secondary_Pattern Pattern_Type WFPC2-LINE Pattern_Purpose DITHER Number_Of_Points 4 Point_Spacing 0.3535 Coordinate_Frame POS-TARG Pattern_Orient 45 Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ 8676( 2) - 05/08/00 16:48 - [ 5] Visit: 01 Visit Priority: 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-0502-6 WFPC2 IMAGE PC1 F555W 1 500 S PATTERN 1 1 801 ------------------------------------------------------------------------------------------------------------------------------------ 2 STAR-0502-6 WFPC2 IMAGE PC1 F555W 1 30 S PATTERN 2 2 801 ------------------------------------------------------------------------------------------------------------------------------------ 3 STAR-0502-6 WFPC2 IMAGE PC1 F675W 1 500 S PATTERN 1 3 801 ------------------------------------------------------------------------------------------------------------------------------------ 4 STAR-0502-6 WFPC2 IMAGE PC1 F675W 1 30 S PATTERN 2 4 801 ------------------------------------------------------------------------------------------------------------------------------------ 5 STAR-0502-6 WFPC2 IMAGE PC1 F814W 1 500 S PATTERN 1 5 801 ------------------------------------------------------------------------------------------------------------------------------------ 6 STAR-0502-6 WFPC2 IMAGE PC1 F814W 1 30 S PATTERN 2 6 801 ------------------------------------------------------------------------------------------------------------------------------------ 8676( 2) - 05/08/00 16:48 - [ 6] Visit: 02 Visit Priority: 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-0506-6 WFPC2 IMAGE PC1 F555W 1 500 S PATTERN 1 1 944 ------------------------------------------------------------------------------------------------------------------------------------ 2 STAR-0506-6 WFPC2 IMAGE PC1 F555W 1 30 S PATTERN 2 2 944 ------------------------------------------------------------------------------------------------------------------------------------ 3 STAR-0506-6 WFPC2 IMAGE PC1 F675W 1 500 S PATTERN 1 3 944 ------------------------------------------------------------------------------------------------------------------------------------ 4 STAR-0506-6 WFPC2 IMAGE PC1 F675W 1 30 S PATTERN 2 4 944 ------------------------------------------------------------------------------------------------------------------------------------ 5 STAR-0506-6 WFPC2 IMAGE PC1 F814W 1 500 S PATTERN 1 5 944 ------------------------------------------------------------------------------------------------------------------------------------ 6 STAR-0506-6 WFPC2 IMAGE PC1 F814W 1 30 S PATTERN 2 6 944 ------------------------------------------------------------------------------------------------------------------------------------ 8676( 2) - 05/08/00 16:48 - [ 7] Visit: 03 Visit Priority: 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-0545-7 WFPC2 IMAGE PC1 F555W 1 500 S PATTERN 1 1 109 ------------------------------------------------------------------------------------------------------------------------------------ 2 STAR-0545-7 WFPC2 IMAGE PC1 F555W 1 30 S PATTERN 2 2 109 ------------------------------------------------------------------------------------------------------------------------------------ 3 STAR-0545-7 WFPC2 IMAGE PC1 F675W 1 500 S PATTERN 1 3 109 ------------------------------------------------------------------------------------------------------------------------------------ 4 STAR-0545-7 WFPC2 IMAGE PC1 F675W 1 30 S PATTERN 2 4 109 ------------------------------------------------------------------------------------------------------------------------------------ 5 STAR-0545-7 WFPC2 IMAGE PC1 F814W 1 500 S PATTERN 1 5 109 ------------------------------------------------------------------------------------------------------------------------------------ 6 STAR-0545-7 WFPC2 IMAGE PC1 F814W 1 30 S PATTERN 2 6 109 ------------------------------------------------------------------------------------------------------------------------------------ 8676( 2) - 05/08/00 16:48 - [ 8] Visit: 04 Visit Priority: 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-0457-6 WFPC2 IMAGE PC1 F555W 1 500 S PATTERN 1 1 928 ------------------------------------------------------------------------------------------------------------------------------------ 2 STAR-0457-6 WFPC2 IMAGE PC1 F555W 1 30 S PATTERN 2 2 928 ------------------------------------------------------------------------------------------------------------------------------------ 3 STAR-0457-6 WFPC2 IMAGE PC1 F675W 1 500 S PATTERN 1 3 928 ------------------------------------------------------------------------------------------------------------------------------------ 4 STAR-0457-6 WFPC2 IMAGE PC1 F675W 1 30 S PATTERN 2 4 928 ------------------------------------------------------------------------------------------------------------------------------------ 5 STAR-0457-6 WFPC2 IMAGE PC1 F814W 1 500 S PATTERN 1 5 928 ------------------------------------------------------------------------------------------------------------------------------------ 6 STAR-0457-6 WFPC2 IMAGE PC1 F814W 1 30 S PATTERN 2 6 928 ------------------------------------------------------------------------------------------------------------------------------------ 8676( 2) - 05/08/00 16:48 - [ 9] Visit: 05 Visit Priority: 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-0506-7 WFPC2 IMAGE PC1 F555W 1 500 S PATTERN 1 1 059 ------------------------------------------------------------------------------------------------------------------------------------ 2 STAR-0506-7 WFPC2 IMAGE PC1 F555W 1 30 S PATTERN 2 2 059 ------------------------------------------------------------------------------------------------------------------------------------ 3 STAR-0506-7 WFPC2 IMAGE PC1 F675W 1 500 S PATTERN 1 3 059 ------------------------------------------------------------------------------------------------------------------------------------ 4 STAR-0506-7 WFPC2 IMAGE PC1 F675W 1 30 S PATTERN 2 4 059 ------------------------------------------------------------------------------------------------------------------------------------ 5 STAR-0506-7 WFPC2 IMAGE PC1 F814W 1 500 S PATTERN 1 5 059 ------------------------------------------------------------------------------------------------------------------------------------ 6 STAR-0506-7 WFPC2 IMAGE PC1 F814W 1 30 S PATTERN 2 6 059 ------------------------------------------------------------------------------------------------------------------------------------ 8676( 2) - 05/08/00 16:48 - [ 10] Visit: 06 Visit Priority: 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-0524-6 WFPC2 IMAGE PC1 F555W 1 500 S PATTERN 1 1 849 ------------------------------------------------------------------------------------------------------------------------------------ 2 STAR-0524-6 WFPC2 IMAGE PC1 F555W 1 30 S PATTERN 2 2 849 ------------------------------------------------------------------------------------------------------------------------------------ 3 STAR-0524-6 WFPC2 IMAGE PC1 F675W 1 500 S PATTERN 1 3 849 ------------------------------------------------------------------------------------------------------------------------------------ 4 STAR-0524-6 WFPC2 IMAGE PC1 F675W 1 30 S PATTERN 2 4 849 ------------------------------------------------------------------------------------------------------------------------------------ 5 STAR-0524-6 WFPC2 IMAGE PC1 F814W 1 500 S PATTERN 1 5 849 ------------------------------------------------------------------------------------------------------------------------------------ 6 STAR-0524-6 WFPC2 IMAGE PC1 F814W 1 30 S PATTERN 2 6 849 ------------------------------------------------------------------------------------------------------------------------------------ 8676( 2) - 05/08/00 16:48 - [ 11] Visit: 07 Visit Priority: 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-0454-7 WFPC2 IMAGE PC1 F555W 1 500 S PATTERN 1 1 002 ------------------------------------------------------------------------------------------------------------------------------------ 2 STAR-0454-7 WFPC2 IMAGE PC1 F555W 1 30 S PATTERN 2 2 002 ------------------------------------------------------------------------------------------------------------------------------------ 3 STAR-0454-7 WFPC2 IMAGE PC1 F675W 1 500 S PATTERN 1 3 002 ------------------------------------------------------------------------------------------------------------------------------------ 4 STAR-0454-7 WFPC2 IMAGE PC1 F675W 1 30 S PATTERN 2 4 002 ------------------------------------------------------------------------------------------------------------------------------------ 5 STAR-0454-7 WFPC2 IMAGE PC1 F814W 1 500 S PATTERN 1 5 002 ------------------------------------------------------------------------------------------------------------------------------------ 6 STAR-0454-7 WFPC2 IMAGE PC1 F814W 1 30 S PATTERN 2 6 002 ------------------------------------------------------------------------------------------------------------------------------------ 8676( 2) - 05/08/00 16:48 - [ 12] Visit: 08 Visit Priority: 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-0506-6 WFPC2 IMAGE PC1 F555W 1 30 S PATTERN 2 1 920 ------------------------------------------------------------------------------------------------------------------------------------ 2 STAR-0506-6 WFPC2 IMAGE PC1 F555W 1 500 S PATTERN 3 2 920 ------------------------------------------------------------------------------------------------------------------------------------ 3 STAR-0506-6 WFPC2 IMAGE PC1 F814W 1 400 S 920 ------------------------------------------------------------------------------------------------------------------------------------ 4 STAR-0506-6 WFPC2 IMAGE PC1 F814W 1 500 S PATTERN 4 4 920 ------------------------------------------------------------------------------------------------------------------------------------ 5 STAR-0506-6 WFPC2 IMAGE PC1 F814W 1 30 S PATTERN 2 5 920 ------------------------------------------------------------------------------------------------------------------------------------ 8676( 2) - 05/08/00 16:48 - [ 13] Summary Form for Proposal 8676 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures PC1 ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFPC2 ------------------------------------------------------------------------------------------------------------------------------------ Opmodes IMAGE ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements PATTERN 1 1 PATTERN 2 2 PATTERN 1 3 PATTERN 2 4 PATTERN 1 5 PATTERN 2 6 PATTERN 2 1 PATTERN 3 2 PATTERN 4 4 PATTERN 2 5 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F555W F675W F814W ------------------------------------------------------------------------------------------------------------------------------------ Target Names STAR-0502-6801 STAR-0506-6944 STAR-0545-7109 STAR-0457-6928 STAR-0506-7059 STAR-0524-6849 STAR-0454-7002 STAR-0506-6920 ------------------------------------------------------------------------------------------------------------------------------------