8203( 13) - 02/10/00 16:56 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 8203 Version: 13 Check-in Date: 10-Feb-2000 16:55:50 1.Proposal Title: Dwarf busting in Abell 868 ------------------------------------------------------------------------------------ 2. Proposal For 3. Cycle GO 8 ------------------------------------------------------------------------------------ 4. Investigators Contact? PI: Simon Driver University of St. Andrews CoI: A/Prof Warrick Couch University of New South Wales N CoI: Prof Rogier Windhorst Arizona State University N CoI: Dr Steve Phillipps University of Bristol N CoI: Dr Steve Odewahn Arizona State University N ------------------------------------------------------------------------------------ 5. Abstract We request 24 orbits to obtain a deep mosaic (6 * 4-orbit pointings) of the central region of A868, a rich Abell cluster which we have imaged comprehensively from the ground. The objective is to identify and characterise the morphological nature of the dwarf galaxy population(s) responsible for the steep upturn seen in this cluster's luminosity function. While similar upturns have been reported in many clusters, the specifics of the dwarf population remain unknown as these objects cannot be resolved from the ground. What type of dwarf galaxies are they ? Is there more than one population contributing ? How are they clustered ? By obtaining deep high-resolution HST WFPC2 imaging over a central field roughly 7.5' * 3.75' we will be able to measure morphologies, light- profiles and the clustering properties of the dwarf population(s) down to M_I = -16 mags (H_o=75kms^-1Mpc^-1). Although we shall primarily concentrate on the dwarf galaxies, we will also recover the cluster's morphological luminosity distributions for elliptical, spirals and irregulars over a broad absolute magnitude range (-24 < M_I < -16 mags) as well as the more quantitative bivariate brightness distribution (- 24 < M_I < -16 mags, 17.0 < mu_e^I < 25 mags per sq arcsec). Comparing these results to those recently derived for the general field will provide an insight into the environmental influences on morphology and surface brightness. ------------------------------------------------------------------------------------ 8203( 13) - 02/10/00 16:56 - [ 2] Observations Description ------------------------ 12 orbits have been allocated specifically in F606W. This results in 6 * 2- orbit pointings (half the requested quota). We intend to image two rows of 3 WFPC2 fields, using the same ORIENT for all six visits. The cD galaxy of A868 will be placed near the center of the PC in visit 1 for later high resolution studies. Real Time Justification ----------------------- The schedulability requirements are not stringent for this mosaic scheme. Calibration Justification ------------------------- Normal photometric calibration data is required Additional Comments ------------------- ------------------------------------------------------------------------------------ Data Distribution Paper Products: YES Media: DAT Blocking Factor: 10 Ship To: PI_Address Ship Via: Email: ------------------------------------------------------------------------------------ 8203( 13) - 02/10/00 16:56 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 ABELL0868- CLUSTER OF GALAXIES, RA=09H 45M 24.9S +/- 0.1", DEC=- J2000 B = 20.0+/-0.5 WNW RICH CLUSTER 08D 39' 18" +/- 1" 2 ABELL0868-N CLUSTER OF GALAXIES, RA=09H 45M 31.8S +/- 0.1", DEC=- J2000 B = 20.0+/-0.1 RICH CLUSTER 08D 38' 56" +/- 1" 3 ABELL0868- CLUSTER OF GALAXIES, RA=09H 45M 38.7S +/- 0.1", DEC=- J2000 B = 20.0+/-0.1 ENE RICH CLUSTER 08D 38' 33" +/- 1" 4 ABELL0868- CLUSTER OF GALAXIES, RA=09H 45M 23.5S +/- 0.1", DEC=- J2000 B = 20.0+/-0.1 WSW RICH CLUSTER 08D 42' 08" +/- 1" 5 ABELL0868-S CLUSTER OF GALAXIES, RA=09H 45M 30.4S +/- 0.1", DEC=- J2000 B = 20.0+/-0.1 RICH CLUSTER 08D 41' 45" +/- 1" 6 ABELL0868- CLUSTER OF GALAXIES, RA=09H 45M 37.3S +/- 0.1", DEC=- J2000 B = 20.0+/-0.1 ESE RICH CLUSTER 08D 41' 23" +/- 1" 8203( 13) - 02/10/00 16:56 - [ 4] Visit: 01 Visit Priority: Visit Requirements: ORIENT 78.00D TO 78.10D 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 ------------------------------------------------------------------------------------------------------------------------------------ 10 ABELL0868-W WFPC2 IMAGE PC1-FIX F606W CR-SPLIT=NO,DITHER-TYPE=BOX 1 1100 S LOW-SKY NO SPLIT SW ------------------------------------------------------------------------------------------------------------------------------------ 8203( 13) - 02/10/00 16:56 - [ 5] Visit: 02 Visit Priority: Visit Requirements: SAME ORIENT AS 01 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 ------------------------------------------------------------------------------------------------------------------------------------ 10 ABELL0868-S WFPC2 IMAGE PC1-FIX F606W CR-SPLIT=NO,DITHER-TYPE=BOX 1 1100 S LOW-SKY NO SPLIT ------------------------------------------------------------------------------------------------------------------------------------ 8203( 13) - 02/10/00 16:56 - [ 6] Visit: 03 Visit Priority: Visit Requirements: SAME ORIENT AS 01 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 ------------------------------------------------------------------------------------------------------------------------------------ 10 ABELL0868-E WFPC2 IMAGE PC1-FIX F606W CR-SPLIT=NO,DITHER-TYPE=BOX 1 1100 S LOW-SKY NO SPLIT SE ------------------------------------------------------------------------------------------------------------------------------------ 8203( 13) - 02/10/00 16:56 - [ 7] Visit: 04 Visit Priority: Visit Requirements: SAME ORIENT AS 01 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 ------------------------------------------------------------------------------------------------------------------------------------ 10 ABELL0868-W WFPC2 IMAGE PC1-FIX F606W CR-SPLIT=NO,DITHER-TYPE=BOX 1 1100 S LOW-SKY NO SPLIT NW ------------------------------------------------------------------------------------------------------------------------------------ 8203( 13) - 02/10/00 16:56 - [ 8] Visit: 05 Visit Priority: Visit Requirements: SAME ORIENT AS 01 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 ------------------------------------------------------------------------------------------------------------------------------------ 10 ABELL0868-N WFPC2 IMAGE PC1-FIX F606W CR-SPLIT=NO,DITHER-TYPE=BOX 1 1100 S LOW-SKY NO SPLIT ------------------------------------------------------------------------------------------------------------------------------------ 8203( 13) - 02/10/00 16:56 - [ 9] Visit: 06 Visit Priority: Visit Requirements: SAME ORIENT AS 01 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 ------------------------------------------------------------------------------------------------------------------------------------ 10 ABELL0868-E WFPC2 IMAGE PC1-FIX F606W CR-SPLIT=NO,DITHER-TYPE=BOX 1 1100 S LOW-SKY NO SPLIT NE ------------------------------------------------------------------------------------------------------------------------------------ 8203( 13) - 02/10/00 16:56 - [ 10] Summary Form for Proposal 8203 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures PC1-FIX ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFPC2 ------------------------------------------------------------------------------------------------------------------------------------ Opmodes IMAGE ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters CR-SPLIT=NO DITHER-TYPE=BOX ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ORIENT 78.00D TO 78.10D LOW-SKY NO SPLIT SAME ORIENT AS 01 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F606W ------------------------------------------------------------------------------------------------------------------------------------ Target Names ABELL0868-WSW ABELL0868-S ABELL0868-ESE ABELL0868-WNW ABELL0868-N ABELL0868-ENE ------------------------------------------------------------------------------------------------------------------------------------