12755( 3) - 11-Oct-2011 18:08:27 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 12755 Version: 3 Check-in Time: 11-Oct-2011 18:08:27 STScI Edit Number: 1 Title Chandra Observations of the Brightest Sunyaev-Zeldovich Effect Cluster ------------------------------------------------------------------------------------ Type Cycle GO 19 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. John P. Hughes Rutgers the State University of New Jersey CoI: Dr. Felipe Menanteau Rutgers the State University of New Jersey N CoI: Dr. Leopoldo Infante Pontificia Universidad Catolica de Chile N CoI: Prof. L Felipe Barrientos Pontificia Universidad Catolica de Chile N CoI: Dr. Rachel Mandelbaum Institute For Advanced Study N ------------------------------------------------------------------------------------ Abstract We propose deep Chandra observations of ACT-CL J0102-4915, the brightest Sunyaev-Zeldovich effect cluster discovered by the Atacama Cosmology Telescope and South Pole Telescope surveys. These surveys covered approximately 3000 square degrees and are essentially complete to high redshift. Our recent Chandra and VLT optical data reveal ACL-CL J0102-4915 to be undergoing a major merger. It is likely a high redshift (z=0.870) counterpart to the famous ÔÔbulletÕÕ cluster. New Chandra data will determine the properties of the merger shock and the HST/ACS data will provide a weak lensing mass map. ------------------------------------------------------------------------------------ Observations Description ------------------------ The target is a rich cluster of galaxies at a redshift of 0.87. The observation goals are to obtain a weak lensing mass measurement and to map the dark matter distribution for comparison with Chandra X-ray data. The cluster is clearly undergoing a major merger and there are two main galaxy distributions separated by 1.2 arcminutes. We will perform a 2 point mosaic in order to cover both galaxy distributions and most of the extent of the X-ray emission. Each pointing is approximately centered on a peak in the galaxy distribution which also allows for a significant region of overlap between the 2 pointings. As clearly stated in our proposal, the alignment of the two galaxy peaks requires us to restrict the orientation angle of the WFC/ACS pointings. The required values are 324 deg for the NW pointing and 322 deg for the SE pointing with an acceptable range of +/- 5 degrees. The given "Fixed Targets" coordinates were optimised for these roll angles. At each point in the mosaic we use one orbit per filter (F625W, F773W, and F850LP). To ensure optimal overlap between these images for color segregation of the galaxies, we schedule each pointing as a separate visit consisting of 3 orbits. We use a 4-point box dither pattern intended to perform 1/2 subpixel sampling and cover the chip gaps of ACS/WFC. 12755( 3) - 11-Oct-2011 18:08:27 - [ 2] Real Time Justification ----------------------- Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ 12755( 3) - 11-Oct-2011 18:08:27 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 ACTJ0102-491 CLUSTER OF GALAXIES, RA=01H02M50.9000S +/- 0.1", J2000 V = 26 5-NW GRAVITATIONAL LENS, DEC=-49D14'25.40" +/- 0.1" HIGH REDSHIFT CLUSTER, RICH CLUSTER Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 2 ACTJ0102-491 CLUSTER OF GALAXIES, RA=01H03M3.1100S +/- 0.1", J2000 V = 26 5-SE GRAVITATIONAL LENS, DEC=-49D16'52.46" +/- 0.1" HIGH REDSHIFT CLUSTER, RICH CLUSTER Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 12755( 3) - 11-Oct-2011 18:08:27 - [ 4] Patterns ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 1 Primary_Pattern Secondary_Pattern Pattern_Type ACS-WFC-DITHER-BOX Pattern_Purpose DITHER Number_Of_Points 4 Point_Spacing 5.943 Line_Spacing 3.077 Coordinate_Frame POS-TARG Pattern_Orient 91.429 Angle_Between_Sides 166.993 Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ 12755( 3) - 11-Oct-2011 18:08:27 - [ 5] Visit: 01 Visit Requirements: ORIENT 319D TO 329 D 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 ACTJ0102-49 ACS/WFC ACCUM WFCENTER F625W 1 586 S GS ACQ SCENARIO SINGLE; 15-NW PATTERN 1 1 ------------------------------------------------------------------------------------------------------------------------------------ 2 ACTJ0102-49 ACS/WFC ACCUM WFCENTER F850LP 1 629 S PATTERN 1 2 15-NW ------------------------------------------------------------------------------------------------------------------------------------ 3 ACTJ0102-49 ACS/WFC ACCUM WFCENTER F775W 1 628 S PATTERN 1 3 15-NW ------------------------------------------------------------------------------------------------------------------------------------ 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 | ------------------------------------------------------------------------------------------------------------------------------------ ACTJ0102-4915-NW 1 ACS/WFC ACCUM WFCENTER F625W 1 none none none 1 N/A ACTJ0102-4915-NW 1 ACS/WFC ACCUM WFCENTER F625W 2 none none none 1 N/A ACTJ0102-4915-NW 1 ACS/WFC ACCUM WFCENTER F625W 3 none none none 1 N/A ACTJ0102-4915-NW 1 ACS/WFC ACCUM WFCENTER F625W 4 none none none 1 N/A ACTJ0102-4915-NW 2 ACS/WFC ACCUM WFCENTER F850LP 1 none none none 2 N/A ACTJ0102-4915-NW 2 ACS/WFC ACCUM WFCENTER F850LP 2 none none none 2 N/A ACTJ0102-4915-NW 2 ACS/WFC ACCUM WFCENTER F850LP 3 none none none 2 N/A ACTJ0102-4915-NW 2 ACS/WFC ACCUM WFCENTER F850LP 4 none none none 2 N/A ACTJ0102-4915-NW 3 ACS/WFC ACCUM WFCENTER F775W 1 none none none 3 N/A ACTJ0102-4915-NW 3 ACS/WFC ACCUM WFCENTER F775W 2 none none none 3 N/A ACTJ0102-4915-NW 3 ACS/WFC ACCUM WFCENTER F775W 3 none none none 3 N/A ACTJ0102-4915-NW 3 ACS/WFC ACCUM WFCENTER F775W 4 none none none 3 N/A 12755( 3) - 11-Oct-2011 18:08:27 - [ 6] Visit: 02 Visit Requirements: ORIENT 317D TO 327 D 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 ACTJ0102-49 ACS/WFC ACCUM WFCENTER F625W 1 586 S PATTERN 1 1 15-SE ------------------------------------------------------------------------------------------------------------------------------------ 2 ACTJ0102-49 ACS/WFC ACCUM WFCENTER F850LP 1 629 S PATTERN 1 2 15-SE ------------------------------------------------------------------------------------------------------------------------------------ 3 ACTJ0102-49 ACS/WFC ACCUM WFCENTER F775W 1 628 S PATTERN 1 3 15-SE ------------------------------------------------------------------------------------------------------------------------------------ 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 | ------------------------------------------------------------------------------------------------------------------------------------ ACTJ0102-4915-SE 1 ACS/WFC ACCUM WFCENTER F625W 1 none none none 1 N/A ACTJ0102-4915-SE 1 ACS/WFC ACCUM WFCENTER F625W 2 none none none 1 N/A ACTJ0102-4915-SE 1 ACS/WFC ACCUM WFCENTER F625W 3 none none none 1 N/A ACTJ0102-4915-SE 1 ACS/WFC ACCUM WFCENTER F625W 4 none none none 1 N/A ACTJ0102-4915-SE 2 ACS/WFC ACCUM WFCENTER F850LP 1 none none none 2 N/A ACTJ0102-4915-SE 2 ACS/WFC ACCUM WFCENTER F850LP 2 none none none 2 N/A ACTJ0102-4915-SE 2 ACS/WFC ACCUM WFCENTER F850LP 3 none none none 2 N/A ACTJ0102-4915-SE 2 ACS/WFC ACCUM WFCENTER F850LP 4 none none none 2 N/A ACTJ0102-4915-SE 3 ACS/WFC ACCUM WFCENTER F775W 1 none none none 3 N/A ACTJ0102-4915-SE 3 ACS/WFC ACCUM WFCENTER F775W 2 none none none 3 N/A ACTJ0102-4915-SE 3 ACS/WFC ACCUM WFCENTER F775W 3 none none none 3 N/A ACTJ0102-4915-SE 3 ACS/WFC ACCUM WFCENTER F775W 4 none none none 3 N/A 12755( 3) - 11-Oct-2011 18:08:27 - [ 7] Summary Form for Proposal 12755 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures WFCENTER ------------------------------------------------------------------------------------------------------------------------------------ Configurations ACS/WFC ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements GS ACQ SCENARIO SINGLE, ORIENT 317D TO 327 D, ORIENT 319D TO 329 D, PATTERN 1 1, PATTERN 1 2, PATTERN 1 3 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F625W, F775W, F850LP ------------------------------------------------------------------------------------------------------------------------------------ Target Names ACTJ0102-4915-NW, ACTJ0102-4915-SE ------------------------------------------------------------------------------------------------------------------------------------