14876( 2) - 14-Dec-2016 14:58:25 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 14876 Version: 2 Check-in Time: 14-Dec-2016 14:58:25 STScI Edit Number: 0 Title Spectacular mergers at the cosmic dawn: a HST, ALMA, and JWST synergy ------------------------------------------------------------------------------------ Type Cycle GO 24 ------------------------------------------------------------------------------------ Investigators Contact? PI: Eduardo Banados Carnegie Institution of Washington Y CoI: Dr. Emanuele Paolo Farina Max-Planck-Institut fur Astronomie, N Heidelberg CoI: Ms. Chiara Giulia Mazzucchelli Max-Planck-Institut fur Astronomie, N Heidelberg CoI: Dr. Bram Venemans Max-Planck-Institut fur Astronomie, N Heidelberg CoI: Dr. Roberto Decarli Max-Planck-Institut fur Astronomie, N Heidelberg CoI: Dr. Fabian Walter Max-Planck-Institut fur Astronomie, N Heidelberg CoI: Prof. Xiaohui Fan University of Arizona N CoI: Dr. Hans-Walter R Rix Max-Planck-Institut fur Astronomie, N Heidelberg CoI: Prof. Frank Bertoldi Universitat Bonn, Argelander Institute for N Astronomy CoI: Dr. Dominik A. Riechers Cornell University N CoI: Dr. Michael A. Strauss Princeton University N CoI: Dr. Ran Wang Peking University N CoI: Dr. Chris Carilli Associated Universities, Inc. N CoI: Dr. Matthew Mechtley Arizona State University N ------------------------------------------------------------------------------------ Abstract How did the first massive galaxies in the universe form? Theoretical models predict that these form through mergers of gas-rich galaxies at very high-redshifts. These models are often invoked to explain the existence of massive `red and dead` galaxies by z~2. We have unexpectedly identified a sample of six z>6 QSOs with close, gas-rich companions at the same redshifts through our on-going ALMA survey of [CII] and dust emission in QSO host galaxies. This is the first unambiguous direct observational evidence of gravitational interactions within the first Gyr of the universe, supporting the aforementioned theoretical models. These newly discovered QSO-galaxy pairs are a unique sample to demonstrate key capabilities of JWST in early science, such as the multi-object and IFU modes of NIRSpec. Remarkably, three of these systems are separated by less than 10 kpc (<2 arcsec), which makes them prime targets to exploit the unparalleled IFU capabilities of JWST/NIRSpec in early science. Such observations will allow us to map the morphology and kinematics of these gravitational interactions as function of separation from the QSOs, which will enlighten our understanding of early black hole and galaxy growth. Thus, it is of critical importance to characterize the rest-frame UV/optical properties of these companions before the JWST launch. Here we propose deep WFC3/IR F140W observations to set the first firm constraints on their rest-frame UV properties, which can only be achieved by the sensitivity and resolution of HST. These timely HST observations 14876( 2) - 14-Dec-2016 14:58:25 - [ 2] will be essential to enable a plethora of JWST early science programs. ------------------------------------------------------------------------------------ Observations Description ------------------------ We aim to characterize the rest-frame UV properties of six faint (J>26) z>6 galaxies very close (<11 arcsec) to bright (J<21) QSOs at the same redshift. We will image each field for one orbit with WFC3/IR F140W to achieve an AB agnitude of ~27 at 5-sigma. These observations will allow us to clearly distinguish between blue, star-forming galaxies and red, obscured galaxies for the whole sample, providing clues to understand the general properties of these newly discovered sources in a statistical manner. We will use the default 4-step box dither pattern (WFC3-IR-DITHER-BOX-MIN) since 1) it gives adequate subpixel sampling to reconstruct nyquist-sampled (2pix/FWHM) images, and 2) it is a commonly-used pattern, which facilitates finding a PSF reference with the same sampling for PSF subtraction purposes. We decided to increase the dither steps to avoid possible self-persistence issues due to the bright quasars. We have restricted the orientations for P167-13 to avoid contamination from difraction spikes from bright stars close to our target. ------------------------------------------------------------------------------------ 14876( 2) - 14-Dec-2016 14:58:25 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 P231-20 GALAXY, HIGH REDSHIFT RA=15H26M37.8410S, J2000 Z = V = 35 +/- 1 expected J>26 GALAXY, INTERACTING DEC=-20D50'0.66" 6.5855 GALAXY, QSO, QUASAR Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 2 P167-13 GALAXY, HIGH REDSHIFT RA=11H10M33.9760S, J2000 Z = V = 35 +/- 1 expected J>26 GALAXY, INTERACTING DEC=-13D29'45.60" 6.5152 GALAXY, QSO, QUASAR Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 3 P308-21 GALAXY, HIGH REDSHIFT RA=20H32M9.9960S, J2000 Z = V = 35 +/- 1 expected J>26 GALAXY, INTERACTING DEC=-21D14'2.31" 6.2430 GALAXY, QSO, QUASAR Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 4 J0842+1218 GALAXY, HIGH REDSHIFT RA=08H42M29.4290S, J2000 Z = V = 35 +/- 1 expected J>26 GALAXY, INTERACTING DEC=+12D18'50.50" 6.0758 GALAXY, QSO, QUASAR Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 5 J2100-1715 GALAXY, HIGH REDSHIFT RA=21H00M54.6160S, J2000 Z = V = 35 +/- 1 expected J>26 GALAXY, INTERACTING DEC=-17D15'22.50" 6.0870 GALAXY, QSO, QUASAR Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 6 J2211-3206 GALAXY, HIGH REDSHIFT RA=22H11M12.3910S, J2000 Z = V = 35 +/- 1 expected J>26 GALAXY, INTERACTING DEC=-32D06'12.94" 6.3360 GALAXY, QSO, QUASAR Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 14876( 2) - 14-Dec-2016 14:58:25 - [ 4] Patterns ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 1 Primary_Pattern Secondary_Pattern Pattern_Type WFC3-IR-DITHER-BOX-MIN Pattern_Purpose DITHER Number_Of_Points 4 Point_Spacing 4.004 Line_Spacing 4.015 Coordinate_Frame POS-TARG Pattern_Orient 18.528 Angle_Between_Sides 74.653 Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ 14876( 2) - 14-Dec-2016 14:58:25 - [ 5] Visit: 01 (P231-20) 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 P231-20 WFC3/IR MULTIAC IR F140W NSAMP=14, SAMP-SEQ=SPARS50 1 DEF PATTERN 1 1 CUM (2611.753 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 | ------------------------------------------------------------------------------------------------------------------------------------ P231-20 1 WFC3/IR MULTIAC IR F140W 1 none none none 1 N/A CUM P231-20 1 WFC3/IR MULTIAC IR F140W 2 none none none 1 N/A CUM P231-20 1 WFC3/IR MULTIAC IR F140W 3 none none none 1 N/A CUM P231-20 1 WFC3/IR MULTIAC IR F140W 4 none none none 1 N/A CUM 14876( 2) - 14-Dec-2016 14:58:25 - [ 6] Visit: 02 (P167-13) Visit Requirements: ORIENT 340D TO 10 D; ORIENT 250D TO 290 D; ORIENT 160D TO 190 D; ORIENT 70D TO 100 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| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 P167-13 WFC3/IR MULTIAC IR F140W NSAMP=14, SAMP-SEQ=SPARS50 1 DEF PATTERN 1 1 CUM (2611.753 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 | ------------------------------------------------------------------------------------------------------------------------------------ P167-13 1 WFC3/IR MULTIAC IR F140W 1 none none none 1 N/A CUM P167-13 1 WFC3/IR MULTIAC IR F140W 2 none none none 1 N/A CUM P167-13 1 WFC3/IR MULTIAC IR F140W 3 none none none 1 N/A CUM P167-13 1 WFC3/IR MULTIAC IR F140W 4 none none none 1 N/A CUM 14876( 2) - 14-Dec-2016 14:58:25 - [ 7] Visit: 03 (P308-21) 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 P308-21 WFC3/IR MULTIAC IR F140W NSAMP=14, SAMP-SEQ=SPARS50 1 DEF PATTERN 1 1 CUM (2611.753 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 | ------------------------------------------------------------------------------------------------------------------------------------ P308-21 1 WFC3/IR MULTIAC IR F140W 1 none none none 1 N/A CUM P308-21 1 WFC3/IR MULTIAC IR F140W 2 none none none 1 N/A CUM P308-21 1 WFC3/IR MULTIAC IR F140W 3 none none none 1 N/A CUM P308-21 1 WFC3/IR MULTIAC IR F140W 4 none none none 1 N/A CUM 14876( 2) - 14-Dec-2016 14:58:25 - [ 8] Visit: 04 (J0842+1218) 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 J0842+1218 WFC3/IR MULTIAC IR F140W NSAMP=14, SAMP-SEQ=SPARS50 1 DEF PATTERN 1 1 CUM (2611.753 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 | ------------------------------------------------------------------------------------------------------------------------------------ J0842+1218 1 WFC3/IR MULTIAC IR F140W 1 none none none 1 N/A CUM J0842+1218 1 WFC3/IR MULTIAC IR F140W 2 none none none 1 N/A CUM J0842+1218 1 WFC3/IR MULTIAC IR F140W 3 none none none 1 N/A CUM J0842+1218 1 WFC3/IR MULTIAC IR F140W 4 none none none 1 N/A CUM 14876( 2) - 14-Dec-2016 14:58:25 - [ 9] Visit: 05 (J2100-1715) 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 J2100-1715 WFC3/IR MULTIAC IR F140W NSAMP=14, SAMP-SEQ=SPARS50 1 DEF PATTERN 1 1 CUM (2611.753 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 | ------------------------------------------------------------------------------------------------------------------------------------ J2100-1715 1 WFC3/IR MULTIAC IR F140W 1 none none none 1 N/A CUM J2100-1715 1 WFC3/IR MULTIAC IR F140W 2 none none none 1 N/A CUM J2100-1715 1 WFC3/IR MULTIAC IR F140W 3 none none none 1 N/A CUM J2100-1715 1 WFC3/IR MULTIAC IR F140W 4 none none none 1 N/A CUM 14876( 2) - 14-Dec-2016 14:58:25 - [ 10] Visit: 06 (J2211-3206) 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 J2211-3206 WFC3/IR MULTIAC IR F140W NSAMP=14, SAMP-SEQ=SPARS50 1 DEF PATTERN 1 1 CUM (2611.753 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 | ------------------------------------------------------------------------------------------------------------------------------------ J2211-3206 1 WFC3/IR MULTIAC IR F140W 1 none none none 1 N/A CUM J2211-3206 1 WFC3/IR MULTIAC IR F140W 2 none none none 1 N/A CUM J2211-3206 1 WFC3/IR MULTIAC IR F140W 3 none none none 1 N/A CUM J2211-3206 1 WFC3/IR MULTIAC IR F140W 4 none none none 1 N/A CUM 14876( 2) - 14-Dec-2016 14:58:25 - [ 11] Summary Form for Proposal 14876 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures IR ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFC3/IR ------------------------------------------------------------------------------------------------------------------------------------ Opmodes MULTIACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters NSAMP=14, SAMP-SEQ=SPARS50 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ORIENT 160D TO 190 D, ORIENT 250D TO 290 D, ORIENT 340D TO 10 D, ORIENT 70D TO 100 D, PATTERN 1 1 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F140W ------------------------------------------------------------------------------------------------------------------------------------ Target Names J0842+1218, J2100-1715, J2211-3206, P167-13, P231-20, P308-21 ------------------------------------------------------------------------------------------------------------------------------------