10407( 3) - 10/27/04 14:45 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 10407 Version: 3 Check-in Date: 27-Oct-2004 18:43:50 1.Proposal Title: When did M31's disk form? ------------------------------------------------------------------------------------ 2. Proposal For 3. Cycle 4. Parallel Pointing Tolerance GO 13 ------------------------------------------------------------------------------------ 5. Investigators Contact? PI: Dr. Heather Morrison Case Western Reserve University CoI: Dr. Nelson C. Caldwell Smithsonian Institution Astrophysical N Observatory CoI: Dr. James Rose University of North Carolina at Chapel N Hill CoI: Dr. Paul Harding Case Western Reserve University N CoI: Dr. Ricardo Schiavon The University of Virginia N ------------------------------------------------------------------------------------ 6. Abstract The recent discovery of THIN disk globular clusters in M31 provides a unique opportunity to determine the age of M31's disk. The globular cluster kinematics imply that the disk has not been significantly heated or destroyed by a merger since they were formed. Thus the cluster ages provide a lower limit to the disk age. This limit will complement the high-redshift data, where few disk galaxies are currently known because of their relatively low surface brighness. We propose to obtain BV ACS imaging of seven disk clusters to below the level of the horizontal branch (HB) to determine the distribution of evolved stars in the color-magnitude diagram. The contribution of evolved stars, particularly blue HB stars, is crucial to estimating the age of the globular cluster from both color-magnitude diagrams and the high S/N integrated spectra which we will obtain from the ground. ------------------------------------------------------------------------------------ 10407( 3) - 10/27/04 14:45 - [ 2] Observations Description ------------------------ We aim to obtain color-magnitude diagrams of the M31 clusters with 5% photometric accuracy in both F435W and F606W at V_0=25.5, just below the horizontal branch. The clusters have reddening values varying from E(B-V)=0.05 to 0.20, which changes required exposures, as does the background level from M31's disk, which all clusters are projected on. We will make small dithers (2 arcsec in x and y, in a linear pattern) to deal with bad pixels and cosmic rays. We have placed the primary targets on the ACS field so that we can also obtain CMDs for another 14 M31 medium-to-bright globular clusters, giving a total of 21 instead of 7 objects. Real Time Justification ----------------------- Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ 10407( 3) - 10/27/04 14:45 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 B366-G291 EXT-CLUSTER, GLOBULAR RA=00H44M46.9200S +/- 1", J2000 V = 25.8 CLUSTER DEC=+42D04'41.33" +/- 1" E(B-V)=0.09 BHB stars (main target) have B-V between 0 and 0.2 Coordinate Source: PPM_STAR_CATALOGUE 2 B224-G279 EXT-CLUSTER, GLOBULAR RA=00H44M24.1000S +/- 1", J2000 V = 25.9 CLUSTER DEC=+41D29'50.00" +/- 1" BHB stars (main target) have B-V between 0 and 0.2; E(B-V)=0.12 Coordinate Source: PPM_STAR_CATALOGUE 3 B171-G222 EXT-CLUSTER, GLOBULAR RA=00H43M29.2000S +/- 1", J2000 V = 25.9 CLUSTER DEC=+41D15'7.43" +/- 1" BHB stars (main target) have B-V between 0 and 0.2; E(B-V)=0.14 Coordinate Source: PPM_STAR_CATALOGUE 4 B234-G290 EXT-CLUSTER, GLOBULAR RA=00H44M45.1000S +/- 1", J2000 V = 25.9 CLUSTER DEC=+41D28'40.70" +/- 1" BHB stars (main target) have B-V between 0 and 0.2; E(B-V)=0.16 Coordinate Source: PPM_STAR_CATALOGUE 5 B206-G257 EXT-CLUSTER, GLOBULAR RA=00H43M57.1600S +/- 1", J2000 V = 25.8 CLUSTER DEC=+41D31'21.40" +/- 1" BHB stars (main target) have B-V between 0 and 0.2 E(B-V)=0.10 Coordinate Source: PPM_STAR_CATALOGUE 6 B057-G118 EXT-CLUSTER, GLOBULAR RA=00H41M47.2900S +/- 1", J2000 V = 25.7 CLUSTER DEC=+40D51'7.70" +/- 1" BHB stars (main target) have B-V between 0 and 0.2 E(B-V)=0.05 Coordinate Source: PPM_STAR_CATALOGUE 7 B008-G60 EXT-CLUSTER, GLOBULAR RA=00H40M30.3200S +/- 1", J2000 V = 26.2 CLUSTER DEC=+41D15'6.20" +/- 1" BHB stars (main target) have B-V between 0 and 0.2; E(B-V)=0.21 Coordinate Source: PPM_STAR_CATALOGUE 10407( 3) - 10/27/04 14:45 - [ 4] Patterns ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 1 Primary_Pattern Secondary_Pattern Pattern_Type ACS-WFC-DITHER-LINE Pattern_Purpose DITHER Number_Of_Points 3 Point_Spacing 0.145 Line_Spacing Coordinate_Frame POS-TARG Pattern_Orient 47.23 Angle_Between_Sides Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 2 Primary_Pattern Secondary_Pattern Pattern_Type ACS-WFC-DITHER-LINE Pattern_Purpose DITHER Number_Of_Points 4 Point_Spacing 0.145 Line_Spacing Coordinate_Frame POS-TARG Pattern_Orient 47.23 Angle_Between_Sides Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ 10407( 3) - 10/27/04 14:45 - [ 5] Visit: 01 Visit Priority: Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 B366-G291 ACS/WFC ACCUM WFC F606W CR-SPLIT=NO 1 620 S PATTERN 1 1-2 see below ------------------------------------------------------------------------------------------------------------------------------------ 2 B366-G291 ACS/WFC ACCUM WFC F435W CR-SPLIT=NO 1 930 S see below ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ B366-G291 1 ACS/WFC ACCUM WFC F606W 1 none none none 1 N/A B366-G291 1 ACS/WFC ACCUM WFC F606W 2 none none none 1 N/A B366-G291 1 ACS/WFC ACCUM WFC F606W 3 none none none 2 610.0 S B366-G291 2 ACS/WFC ACCUM WFC F435W 1 none none none 1 1100.0 S B366-G291 2 ACS/WFC ACCUM WFC F435W 2 none none none 2 910.0 S B366-G291 2 ACS/WFC ACCUM WFC F435W 3 none none none 2 910.0 S 10407( 3) - 10/27/04 14:45 - [ 6] Visit: 02 Visit Priority: Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 B224-G279 ACS/WFC ACCUM WFC F606W CR-SPLIT=NO 1 620 S PATTERN 1 1-2 ------------------------------------------------------------------------------------------------------------------------------------ 2 B224-G279 ACS/WFC ACCUM WFC F435W CR-SPLIT=NO 1 930 S see below ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ B224-G279 1 ACS/WFC ACCUM WFC F606W 1 none none none 1 N/A B224-G279 1 ACS/WFC ACCUM WFC F606W 2 none none none 1 N/A B224-G279 1 ACS/WFC ACCUM WFC F606W 3 none none none 2 N/A B224-G279 2 ACS/WFC ACCUM WFC F435W 1 none none none 1 1100.0 S B224-G279 2 ACS/WFC ACCUM WFC F435W 2 none none none 2 910.0 S B224-G279 2 ACS/WFC ACCUM WFC F435W 3 none none none 2 900.0 S 10407( 3) - 10/27/04 14:45 - [ 7] Visit: 03 Visit Priority: Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 B171-G222 ACS/WFC ACCUM WFC F606W CR-SPLIT=NO 1 900 S PATTERN 1 1-2 see below ------------------------------------------------------------------------------------------------------------------------------------ 2 B171-G222 ACS/WFC ACCUM WFC F435W CR-SPLIT=NO 1 1260 S see below ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ B171-G222 1 ACS/WFC ACCUM WFC F606W 1 none none none 1 1104.0 S B171-G222 1 ACS/WFC ACCUM WFC F606W 2 none none none 2 1146.0 S B171-G222 1 ACS/WFC ACCUM WFC F606W 3 none none none 3 1146.0 S B171-G222 2 ACS/WFC ACCUM WFC F435W 1 none none none 1 1464.0 S B171-G222 2 ACS/WFC ACCUM WFC F435W 2 none none none 2 1506.0 S B171-G222 2 ACS/WFC ACCUM WFC F435W 3 none none none 3 1506.0 S 10407( 3) - 10/27/04 14:45 - [ 8] Visit: 04 Visit Priority: Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 B234-G290 ACS/WFC ACCUM WFC F606W CR-SPLIT=NO 1 700 S PATTERN 1 1-2 see below ------------------------------------------------------------------------------------------------------------------------------------ 2 B234-G290 ACS/WFC ACCUM WFC F435W CR-SPLIT=NO 1 1115 S see below ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ B234-G290 1 ACS/WFC ACCUM WFC F606W 1 none none none 1 1077.0 S B234-G290 1 ACS/WFC ACCUM WFC F606W 2 none none none 2 1119.0 S B234-G290 1 ACS/WFC ACCUM WFC F606W 3 none none none 3 1119.0 S B234-G290 2 ACS/WFC ACCUM WFC F435W 1 none none none 1 1492.0 S B234-G290 2 ACS/WFC ACCUM WFC F435W 2 none none none 2 1534.0 S B234-G290 2 ACS/WFC ACCUM WFC F435W 3 none none none 3 1534.0 S 10407( 3) - 10/27/04 14:45 - [ 9] Visit: 05 Visit Priority: Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 B206-G257 ACS/WFC ACCUM WFC F606W CR-SPLIT=NO 1 620 S PATTERN 1 1-2 see below ------------------------------------------------------------------------------------------------------------------------------------ 2 B206-G257 ACS/WFC ACCUM WFC F435W CR-SPLIT=NO 1 920 S see below ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ B206-G257 1 ACS/WFC ACCUM WFC F606W 1 none none none 1 N/A B206-G257 1 ACS/WFC ACCUM WFC F606W 2 none none none 1 N/A B206-G257 1 ACS/WFC ACCUM WFC F606W 3 none none none 2 600.0 S B206-G257 2 ACS/WFC ACCUM WFC F435W 1 none none none 1 1100.0 S B206-G257 2 ACS/WFC ACCUM WFC F435W 2 none none none 2 905.0 S B206-G257 2 ACS/WFC ACCUM WFC F435W 3 none none none 2 N/A 10407( 3) - 10/27/04 14:45 - [ 10] Visit: 06 Visit Priority: Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 B057-G118 ACS/WFC ACCUM WFC F606W CR-SPLIT=NO 1 600 S PATTERN 1 1-2 see below ------------------------------------------------------------------------------------------------------------------------------------ 2 B057-G118 ACS/WFC ACCUM WFC F435W CR-SPLIT=NO 1 800 S see below ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ B057-G118 1 ACS/WFC ACCUM WFC F606W 1 none none none 1 716.0 S B057-G118 1 ACS/WFC ACCUM WFC F606W 2 none none none 1 716.0 S B057-G118 1 ACS/WFC ACCUM WFC F606W 3 none none none 2 678.0 S B057-G118 2 ACS/WFC ACCUM WFC F435W 1 none none none 1 916.0 S B057-G118 2 ACS/WFC ACCUM WFC F435W 2 none none none 2 878.0 S B057-G118 2 ACS/WFC ACCUM WFC F435W 3 none none none 2 878.0 S 10407( 3) - 10/27/04 14:45 - [ 11] Visit: 07 Visit Priority: Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 B008-G60 ACS/WFC ACCUM WFC F606W CR-SPLIT=NO 1 800 S PATTERN 2 1-2 see below ------------------------------------------------------------------------------------------------------------------------------------ 2 B008-G60 ACS/WFC ACCUM WFC F435W CR-SPLIT=NO 1 1800 S see below ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ B008-G60 1 ACS/WFC ACCUM WFC F606W 1 none none none 1 N/A B008-G60 1 ACS/WFC ACCUM WFC F606W 2 none none none 2 850.0 S B008-G60 1 ACS/WFC ACCUM WFC F606W 3 none none none 3 N/A B008-G60 1 ACS/WFC ACCUM WFC F606W 4 none none none 4 N/A B008-G60 2 ACS/WFC ACCUM WFC F435W 1 none none none 1 1760.0 S B008-G60 2 ACS/WFC ACCUM WFC F435W 2 none none none 2 N/A B008-G60 2 ACS/WFC ACCUM WFC F435W 3 none none none 3 1850.0 S B008-G60 2 ACS/WFC ACCUM WFC F435W 4 none none none 4 1850.0 S 10407( 3) - 10/27/04 14:45 - [ 12] Summary Form for Proposal 10407 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures WFC ------------------------------------------------------------------------------------------------------------------------------------ Configurations ACS/WFC ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters CR-SPLIT=NO ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements PATTERN 1 1-2 PATTERN 2 1-2 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F606W F435W ------------------------------------------------------------------------------------------------------------------------------------ Target Names B366-G291 B224-G279 B171-G222 B234-G290 B206-G257 B057-G118 B008-G60 ------------------------------------------------------------------------------------------------------------------------------------