16027( 1) - 08-Oct-2019 15:35:29 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 16027 Version: 1 Check-in Time: 08-Oct-2019 15:35:29 STScI Edit Number: 1 Title Beyond MACS: A Snapshot Survey of the Most Massive Clusters of Galaxies at z>0.5 ------------------------------------------------------------------------------------ Type Cycle SNAP 26 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. Harald Ebeling University of Hawaii Y CoI: Prof. Jean-Paul Richard Kneib Ecole Polytechnique Federale de Lausanne N CoI: Dr. Alastair C. Edge Durham Univ. N CoI: Dr. Nick Kaiser Ecole Normale Superieure N CoI: Dr. Johan Pierre Richard Centre de Recherche Astrophysique de Lyon N CoI: Dr. Benjamin Clement Centre de Recherche Astrophysique de Lyon N CoI: Dr. Sune Toft University of Copenhagen, Niels Bohr N Institute CoI: Dr. Marceau Limousin Laboratoire d'Astrophysique de Marseille N CoI: Dr. Hakim Atek CNRS, Institut d'Astrophysique de Paris N CoI: Mr. Conor McPartland University of Hawaii N CoI: Mr. Andrew Repp University of Hawaii N ------------------------------------------------------------------------------------ Abstract Truly massive galaxy clusters play a pivotal role for a wealth of extragalactic and cosmological research topics, and SNAPshot observations of these systems are ideally suited to identify the most promising cluster targets for further, in-depth study. The power of this approach was demonstrated by ACS/WFC3 SNAPshots of X-ray selected MACS and eMACS clusters at z>0.3 obtained by us in previous Cycles (44 of them in all of F606W, F814W, F110W, and F140W). Based on these data, the CLASH MCT program selected 16 out of 25 of their targets to be MACS clusters. Similarly, all but one of the six most powerful cluster lenses selected for in-depth study by the HST Frontier Fields initiative are MACS detections, and so are 16 of the 29 z>0.3 clusters targeted by the RELICS legacy program. We propose to extend our spectacularly successful SNAPshot survey of the most X-ray luminous distant clusters to a redshift-mass regime that is poorly sampled by any other project. Targeting only extremely massive clusters at z>0.5 from the X-ray selected eMACS sample (median velocity dispersion: 1180 km/s), the proposed program will (a) identify the most powerful gravitational telescopes at yet higher redshift for the next generation of in-depth studies of the distant Universe with HST and JWST, (b) provide constraints on the mass distribution within these extreme systems, (c) help improve our understanding of the physical nature of galaxy-galaxy and galaxy-gas interactions in cluster cores, and (d) unveil Balmer Break Galaxies at z~2 and Lyman-break galaxies at z>6 as F814W dropouts. Acknowledging the broad community interest in our sample we waive our data rights for these observations. ------------------------------------------------------------------------------------ Observations Description ------------------------ 16027( 1) - 08-Oct-2019 15:35:29 - [ 2] We propose ACS and WFC3 SNAPshot observations of all eMACS clusters at z>0.5 not yet observed with HST in our program's four filters. Our targets are uniformly distributed over the high-Galactic latitude sky (|b|>20 deg), dec > -30 deg, making ours an ideal SNAPshot sample. Since all of our science goals require or greatly benefit from color information, we aim for three independent visits per cluster target (one each for ACS/F606W and F814W imaging, and a third one for SNAPshots with WFC3/F110W/F140W). Counting each visit as a separate target (as indicated in Section 3.3.3 of the CfP) but discounting visits already performed for some of our targets in previous SNAP programs, we are left with 174 distinct "targets". Some of these will be used as backup (we suspect the respective clusters to be less massive than suggested by the RASS X-ray luminosity). From the remainder, 166 visits will be selected to match the number of orbits awarded. ------------------------------------------------------------------------------------ 16027( 1) - 08-Oct-2019 15:35:29 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 35 EMACSJ1350.7 CLUSTER OF GALAXIES, RA=13H50M46.4350S, J2000 V = 20.0 -1055 HIGH REDSHIFT CLUSTER DEC=-10D55'32.24" Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 16027( 1) - 08-Oct-2019 15:35:29 - [ 4] Patterns ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 1 Primary_Pattern Secondary_Pattern Pattern_Type ACS-WFC-DITHER-LINE Pattern_Purpose DITHER Number_Of_Points 3 Point_Spacing 3.011 Line_Spacing Coordinate_Frame POS-TARG Pattern_Orient 85.28 Angle_Between_Sides Center_Pattern YES ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 2 Primary_Pattern Secondary_Pattern Pattern_Type WFC3-IR-DITHER-LINE Pattern_Purpose DITHER Number_Of_Points 2 Point_Spacing 0.636 Line_Spacing Coordinate_Frame POS-TARG Pattern_Orient 41.788 Angle_Between_Sides Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ 16027( 1) - 08-Oct-2019 15:35:29 - [ 5] Visit: 1D 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| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 EMACSJ1350. WFC3/IR MULTIAC IR F110W SAMP-SEQ=SPARS25, NSAMP=15 1 DEF PATTERN 2 1 7-1055 CUM (705.879 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 EMACSJ1350. WFC3/IR MULTIAC IR F140W SAMP-SEQ=SPARS25, NSAMP=15 1 DEF PATTERN 2 2 7-1055 CUM (705.879 S) ------------------------------------------------------------------------------------------------------------------------------------ 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 | ------------------------------------------------------------------------------------------------------------------------------------ EMACSJ1350.7-1055 1 WFC3/IR MULTIAC IR F110W 1 none none none 1 N/A CUM EMACSJ1350.7-1055 1 WFC3/IR MULTIAC IR F110W 2 none none none 1 N/A CUM EMACSJ1350.7-1055 2 WFC3/IR MULTIAC IR F140W 1 none none none 1 N/A CUM EMACSJ1350.7-1055 2 WFC3/IR MULTIAC IR F140W 2 none none none 1 N/A CUM 16027( 1) - 08-Oct-2019 15:35:29 - [ 6] Visit: 31 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| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 EMACSJ1350. ACS/WFC ACCUM WFC F606W CR-SPLIT=NO 1 400 S PATTERN 1 1 7-1055 (1200 S) ------------------------------------------------------------------------------------------------------------------------------------ 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 | ------------------------------------------------------------------------------------------------------------------------------------ EMACSJ1350.7-1055 1 ACS/WFC ACCUM WFC F606W 1 none none none 1 N/A EMACSJ1350.7-1055 1 ACS/WFC ACCUM WFC F606W 2 none none none 1 N/A EMACSJ1350.7-1055 1 ACS/WFC ACCUM WFC F606W 3 none none none 1 N/A 16027( 1) - 08-Oct-2019 15:35:29 - [ 7] Visit: 84 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| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 EMACSJ1350. ACS/WFC ACCUM WFC F814W CR-SPLIT=NO 1 400 S PATTERN 1 1 7-1055 (1200 S) ------------------------------------------------------------------------------------------------------------------------------------ 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 | ------------------------------------------------------------------------------------------------------------------------------------ EMACSJ1350.7-1055 1 ACS/WFC ACCUM WFC F814W 1 none none none 1 N/A EMACSJ1350.7-1055 1 ACS/WFC ACCUM WFC F814W 2 none none none 1 N/A EMACSJ1350.7-1055 1 ACS/WFC ACCUM WFC F814W 3 none none none 1 N/A 16027( 1) - 08-Oct-2019 15:35:29 - [ 8] Summary Form for Proposal 16027 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures IR, WFC ------------------------------------------------------------------------------------------------------------------------------------ Configurations ACS/WFC, WFC3/IR ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM, MULTIACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters CR-SPLIT=NO, NSAMP=15, SAMP-SEQ=SPARS25 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements PATTERN 1 1, PATTERN 2 1, PATTERN 2 2 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F110W, F140W, F606W, F814W ------------------------------------------------------------------------------------------------------------------------------------ Target Names EMACSJ1350.7-1055 ------------------------------------------------------------------------------------------------------------------------------------