16037( 3) - 27-Nov-2019 15:28:47 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 16037 Version: 3 Check-in Time: 27-Nov-2019 15:28:47 STScI Edit Number: 1 Title Securing a sample of exceptionally bright z>~9 galaxies to prepare for JWST and probe early galaxy assembly ------------------------------------------------------------------------------------ Type Cycle GO 27 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. Mauro Stefanon Universiteit Leiden Y CoI: Dr. Rychard Bouwens Universiteit Leiden N CoI: Prof. Pascal Oesch Observatoire de Geneve N CoI: Prof. Ivo Labbe Swinburne University of Technology N CoI: Dr. Renske Smit University of Cambridge N CoI: Prof. Garth D. Illingworth University of California - Santa Cruz N CoI: Ryan Endsley University of Arizona N CoI: Dr. Gabriel Brammer University of Copenhagen, Niels Bohr N Institute CoI: Dr. Themiya Nanayakkara Universiteit Leiden N CoI: Sander Schouws Sterrewacht Leiden N ------------------------------------------------------------------------------------ Abstract Especially massive galaxies are thought to be rare in the high-redshift universe, so the discovery of one very bright z=11.1 galaxy (GN-z11) within the original CANDELS program (0.25 sq. deg) was quite a surprise. Most theoretical models suggested a 10-50x larger area would be required to identify such a source. While such a discovery could suggest high-mass galaxies form particularly efficiently at early times, it could also be a "lucky" find. To determine which and to probe the properties of the most massive assembled galaxies in the early universe, we search a much larger volume for bright z>8.5 galaxies and discovered 4 very bright, high-probability z~9-10 candidate galaxies over that 6 square degree area with the deepest optical, near-IR, and Spitzer/IRAC data. The extreme luminosities of these sources demands that we urgently try to confirm their nature as secure z>8 galaxies with deeper follow-up observations given the implications for the formation efficiency of massive galaxies in the early universe and the proximity of the JWST cycle 1 deadline. With just 1 orbit of HST imaging data at 0.1 micron, these candidates would be detected at 10 sigma if at z<7, or be found to be secure >99.9999%-probability z>8 galaxies if undetected. Thanks to the very large volumes we search, we will likely confirm 1 of these extreme sources as robust, and potentially more if galaxy formation is especially efficient at early times. Our resultant sample of exceptionally bright z~9-10 galaxies should serve as high value targets for deep spectroscopy in the near future with JWST, ALMA, and also with the ELTs. ------------------------------------------------------------------------------------ Observations Description ------------------------ We observe 4 candidate ultrabright (mH~24-24.5 A) star-forming galaxies at z>8.5. Each source is observed during one visit for one orbit split between imaging in the F105W (~0.8 orbit) and F140W (~0.2 orbit) bands. We adopt a 4-point dither strategy in F105W (3-point for F140W), similar to the 16037( 3) - 27-Nov-2019 15:28:47 - [ 2] WFC3-IR-DITHER-BOX-MIN pattern, to improve spatial sampling and limit systematics from potential cosmetic defects and residual cosmic ray hits, and alternating observations in the F140W to those in the F105W band, to optimize the time available for integration. Furthermore, each orbit starts and ends with observations in the F140W, to limit the contamination from HeII emission that could affect the F105W band at low limb angles from earth. We minimized the sampling time of each integration to pursue optimal cosmic ray rejection. In the event of Reduced Gyro Mode, given the current short (17-20sec) unused time in each orbit, our observing strategy would need minor revision to accommodate the additional ~2minutes required for the initial target acquisition. ------------------------------------------------------------------------------------ 16037( 3) - 27-Nov-2019 15:28:47 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 246557 GALAXY, HIGH REDSHIFT RA=02H21M56.6693S, J2000 V = 35 H=24 AB GALAXY DEC=-04D42'44.17" Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 2 290767 GALAXY, HIGH REDSHIFT RA=02H28M36.6304S, J2000 V = 35 H=24 AB GALAXY DEC=-04D35'34.55" Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 3 104648 GALAXY, HIGH REDSHIFT RA=02H25M37.7299S, J2000 V = 35 H=24 AB GALAXY DEC=-05D06'53.44" Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 4 265881 GALAXY, HIGH REDSHIFT RA=02H28M23.0883S, J2000 V = 35 H=24 AB GALAXY DEC=-04D38'24.60" Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 16037( 3) - 27-Nov-2019 15:28:47 - [ 4] Visit: 01 (246557) 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 246557 WFC3/IR MULTIAC IR F140W SAMP-SEQ=SPARS25, NSAMP=9 1 DEF CUM (202.936 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 246557 WFC3/IR MULTIAC IR F105W SAMP-SEQ=SPARS50, NSAMP=10 1 DEF SAME POS AS 1 CUM (452.936 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 246557 WFC3/IR MULTIAC IR F105W SAMP-SEQ=SPARS50, NSAMP=11 1 DEF POS TARG 0.813000, CUM (502.937 0.423850 S) ------------------------------------------------------------------------------------------------------------------------------------ 4 246557 WFC3/IR MULTIAC IR F105W SAMP-SEQ=SPARS50, NSAMP=11 1 DEF POS TARG 0.609750, CUM (502.937 0.726600 S) ------------------------------------------------------------------------------------------------------------------------------------ 5 246557 WFC3/IR MULTIAC IR F140W SAMP-SEQ=SPARS25, NSAMP=7 1 DEF SAME POS AS 4 CUM (152.935 S) ------------------------------------------------------------------------------------------------------------------------------------ 6 246557 WFC3/IR MULTIAC IR F105W SAMP-SEQ=SPARS50, NSAMP=11 1 DEF POS TARG -0.474250, CUM (502.937 0.544950 S) ------------------------------------------------------------------------------------------------------------------------------------ 7 246557 WFC3/IR MULTIAC IR F140W SAMP-SEQ=SPARS25, NSAMP=7 1 DEF SAME POS AS 6 CUM (152.935 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 | ------------------------------------------------------------------------------------------------------------------------------------ 246557 1 WFC3/IR MULTIAC IR F140W none none none none 1 N/A CUM 246557 2 WFC3/IR MULTIAC IR F105W none none none none 1 N/A CUM 246557 3 WFC3/IR MULTIAC IR F105W none none none none 1 N/A CUM 246557 4 WFC3/IR MULTIAC IR F105W none none none none 1 N/A CUM 16037( 3) - 27-Nov-2019 15:28:47 - [ 5] 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 | ------------------------------------------------------------------------------------------------------------------------------------ 246557 5 WFC3/IR MULTIAC IR F140W none none none none 1 N/A CUM 246557 6 WFC3/IR MULTIAC IR F105W none none none none 1 N/A CUM 246557 7 WFC3/IR MULTIAC IR F140W none none none none 1 N/A CUM 16037( 3) - 27-Nov-2019 15:28:47 - [ 6] Visit: 02 (290767) 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 290767 WFC3/IR MULTIAC IR F140W SAMP-SEQ=SPARS25, NSAMP=9 1 DEF CUM (202.936 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 290767 WFC3/IR MULTIAC IR F105W SAMP-SEQ=SPARS50, NSAMP=10 1 DEF SAME POS AS 1 CUM (452.936 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 290767 WFC3/IR MULTIAC IR F105W SAMP-SEQ=SPARS50, NSAMP=11 1 DEF POS TARG 0.813000, CUM (502.937 0.423850 S) ------------------------------------------------------------------------------------------------------------------------------------ 4 290767 WFC3/IR MULTIAC IR F105W SAMP-SEQ=SPARS50, NSAMP=11 1 DEF POS TARG 0.609750, CUM (502.937 0.726600 S) ------------------------------------------------------------------------------------------------------------------------------------ 5 290767 WFC3/IR MULTIAC IR F140W SAMP-SEQ=SPARS25, NSAMP=7 1 DEF SAME POS AS 4 CUM (152.935 S) ------------------------------------------------------------------------------------------------------------------------------------ 6 290767 WFC3/IR MULTIAC IR F105W SAMP-SEQ=SPARS50, NSAMP=11 1 DEF POS TARG -0.474250, CUM (502.937 0.544950 S) ------------------------------------------------------------------------------------------------------------------------------------ 7 290767 WFC3/IR MULTIAC IR F140W SAMP-SEQ=SPARS25, NSAMP=7 1 DEF SAME POS AS 6 CUM (152.935 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 | ------------------------------------------------------------------------------------------------------------------------------------ 290767 1 WFC3/IR MULTIAC IR F140W none none none none 1 N/A CUM 290767 2 WFC3/IR MULTIAC IR F105W none none none none 1 N/A CUM 290767 3 WFC3/IR MULTIAC IR F105W none none none none 1 N/A CUM 290767 4 WFC3/IR MULTIAC IR F105W none none none none 1 N/A CUM 16037( 3) - 27-Nov-2019 15:28:47 - [ 7] 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 | ------------------------------------------------------------------------------------------------------------------------------------ 290767 5 WFC3/IR MULTIAC IR F140W none none none none 1 N/A CUM 290767 6 WFC3/IR MULTIAC IR F105W none none none none 1 N/A CUM 290767 7 WFC3/IR MULTIAC IR F140W none none none none 1 N/A CUM 16037( 3) - 27-Nov-2019 15:28:47 - [ 8] Visit: 03 (104648) 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 104648 WFC3/IR MULTIAC IR F140W SAMP-SEQ=SPARS25, NSAMP=9 1 DEF GS ACQ SCENARIO BASE1B3 CUM (202.936 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 104648 WFC3/IR MULTIAC IR F105W SAMP-SEQ=SPARS50, NSAMP=10 1 DEF SAME POS AS 1 CUM (452.936 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 104648 WFC3/IR MULTIAC IR F105W SAMP-SEQ=SPARS50, NSAMP=11 1 DEF POS TARG 0.813000, CUM (502.937 0.423850 S) ------------------------------------------------------------------------------------------------------------------------------------ 4 104648 WFC3/IR MULTIAC IR F105W SAMP-SEQ=SPARS50, NSAMP=11 1 DEF POS TARG 0.609750, CUM (502.937 0.726600 S) ------------------------------------------------------------------------------------------------------------------------------------ 5 104648 WFC3/IR MULTIAC IR F140W SAMP-SEQ=SPARS25, NSAMP=7 1 DEF SAME POS AS 4 CUM (152.935 S) ------------------------------------------------------------------------------------------------------------------------------------ 6 104648 WFC3/IR MULTIAC IR F105W SAMP-SEQ=SPARS50, NSAMP=11 1 DEF POS TARG -0.474250, CUM (502.937 0.544950 S) ------------------------------------------------------------------------------------------------------------------------------------ 7 104648 WFC3/IR MULTIAC IR F140W SAMP-SEQ=SPARS25, NSAMP=7 1 DEF SAME POS AS 6 CUM (152.935 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 | ------------------------------------------------------------------------------------------------------------------------------------ 104648 1 WFC3/IR MULTIAC IR F140W none none none none 1 N/A CUM 104648 2 WFC3/IR MULTIAC IR F105W none none none none 1 N/A CUM 104648 3 WFC3/IR MULTIAC IR F105W none none none none 1 N/A CUM 104648 4 WFC3/IR MULTIAC IR F105W none none none none 1 N/A CUM 16037( 3) - 27-Nov-2019 15:28:47 - [ 9] 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 | ------------------------------------------------------------------------------------------------------------------------------------ 104648 5 WFC3/IR MULTIAC IR F140W none none none none 1 N/A CUM 104648 6 WFC3/IR MULTIAC IR F105W none none none none 1 N/A CUM 104648 7 WFC3/IR MULTIAC IR F140W none none none none 1 N/A CUM 16037( 3) - 27-Nov-2019 15:28:47 - [ 10] Visit: 04 (265881) 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 265881 WFC3/IR MULTIAC IR F140W SAMP-SEQ=SPARS25, NSAMP=9 1 DEF CUM (202.936 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 265881 WFC3/IR MULTIAC IR F105W SAMP-SEQ=SPARS50, NSAMP=10 1 DEF SAME POS AS 1 CUM (452.936 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 265881 WFC3/IR MULTIAC IR F105W SAMP-SEQ=SPARS50, NSAMP=11 1 DEF POS TARG 0.813000, CUM (502.937 0.423850 S) ------------------------------------------------------------------------------------------------------------------------------------ 4 265881 WFC3/IR MULTIAC IR F105W SAMP-SEQ=SPARS50, NSAMP=11 1 DEF POS TARG 0.609750, CUM (502.937 0.726600 S) ------------------------------------------------------------------------------------------------------------------------------------ 5 265881 WFC3/IR MULTIAC IR F140W SAMP-SEQ=SPARS25, NSAMP=7 1 DEF SAME POS AS 4 CUM (152.935 S) ------------------------------------------------------------------------------------------------------------------------------------ 6 265881 WFC3/IR MULTIAC IR F105W SAMP-SEQ=SPARS50, NSAMP=11 1 DEF POS TARG -0.474250, CUM (502.937 0.544950 S) ------------------------------------------------------------------------------------------------------------------------------------ 7 265881 WFC3/IR MULTIAC IR F140W SAMP-SEQ=SPARS25, NSAMP=7 1 DEF SAME POS AS 6 CUM (152.935 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 | ------------------------------------------------------------------------------------------------------------------------------------ 265881 1 WFC3/IR MULTIAC IR F140W none none none none 1 N/A CUM 265881 2 WFC3/IR MULTIAC IR F105W none none none none 1 N/A CUM 265881 3 WFC3/IR MULTIAC IR F105W none none none none 1 N/A CUM 265881 4 WFC3/IR MULTIAC IR F105W none none none none 1 N/A CUM 16037( 3) - 27-Nov-2019 15:28:47 - [ 11] 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 | ------------------------------------------------------------------------------------------------------------------------------------ 265881 5 WFC3/IR MULTIAC IR F140W none none none none 1 N/A CUM 265881 6 WFC3/IR MULTIAC IR F105W none none none none 1 N/A CUM 265881 7 WFC3/IR MULTIAC IR F140W none none none none 1 N/A CUM 16037( 3) - 27-Nov-2019 15:28:47 - [ 12] Summary Form for Proposal 16037 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures IR ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFC3/IR ------------------------------------------------------------------------------------------------------------------------------------ Opmodes MULTIACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters NSAMP=10, NSAMP=11, NSAMP=7, NSAMP=9, SAMP-SEQ=SPARS25, SAMP-SEQ=SPARS50 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements GS ACQ SCENARIO BASE1B3, POS TARG 0.813000, 0.423850, POS TARG -0.474250, 0.544950, POS TARG 0.609750, 0.726600, SAME POS AS 1, SAME POS AS 4, SAME POS AS 6 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F105W, F140W ------------------------------------------------------------------------------------------------------------------------------------ Target Names 104648, 246557, 265881, 290767 ------------------------------------------------------------------------------------------------------------------------------------