15200( 3) - 06-Sep-2017 13:11:26 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 15200 Version: 3 Check-in Time: 06-Sep-2017 13:11:26 STScI Edit Number: 0 Title A case study of an extremely luminous, highly spatially extended starburst only 1.7Gyr after the Big Bang ------------------------------------------------------------------------------------ Type Cycle GO 25 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. Duncan Farrah Virginia Polytechnic Institute and State Y University CoI: Dr. David Clements Imperial College of Science Technology and N Medicine CoI: Dr. Ismael Perez-Fournon Instituto de Astrofisica de Canarias N CoI: Glen Petitpas Smithsonian Institution Astrophysical N Observatory CoI: Mr. Joshua Greenslade Imperial College of Science Technology and N Medicine ------------------------------------------------------------------------------------ Abstract Luminous starbursts, systems with SFRs exceeding ~1000Msun yr-1, are predicted to be extremely rare at z>3. However, recent observations find such systems at rates of tens to hundreds above predictions. This discrepancy is extremely difficult to explain. Case studies of such luminous starbursts are thus of profound importance to understand how star formation is triggered and quenched at z > 3, and help reconcile models with observations. Our group has been intensively studying the quasar SDSS J160705.16, at z = 3.65 (or 1.7Gyr after the Big Bang). This quasar is an excellent case study of luminous star formation at z > 3, and how AGN activity may affect such star formation. SDSS J160705.16 harbors both a broad-line, luminous quasar and an extremely high star formation rate, with an AGN luminosity of ~10^47 ergs s-1 and an SFR of ~2000 Msol yr-1. Sub-mm interferometry has further revealed that the star formation is highly spatially extended on scales up to 40kpc. Furthermore, VLA observations show an emerging ~4kpc radio jet. We here propose WFC3 imaging with the following goals: (1) to set precise constraints on any lensing magnification, (2) to determine the morphology and color structure of the extended star formation, (3) to compare the optical morphology of the star formation to that seen in the sub-mm data, and (4) to search for evidence that SDSS J160705.16 resides in a protocluster. ------------------------------------------------------------------------------------ Observations Description ------------------------ We observe with WFC3/IR as the high redshift of J160705 makes near-infrared observations optimal. Observations with e.g. F814W or shorter would be heavily contaminated by line emission, or sample below the Lyman break. We observe with two filters to estimate spatially resolved star formation rates and extinctions, and to use color gradient as a diagnostic of activity. At z=3.6, F110W and F160W sample rest-frame near-UV and U-band, respectively, and are 15200( 3) - 06-Sep-2017 13:11:26 - [ 2] both longward of the brightest ultraviolet emission lines, meaning that the morphologies and colors as a function of position can be translated into estimates of star formation rate and reddening straightforwardly. To determine the total exposure time we normalize a set of starburst SED templates for slightly to moderately obscured star formation to the flux in the extended submm emission. The median SED shape in this library corresponds approximately to that of the starburst galaxy M82, but includes systems as obscured as Arp220. We then extract the {\itshape maximum-likelihood} flux densities at observed-frame wavelengths corresponding to F110W and F160W, and then assume that this emission is distributed over a comparable spatial scale to the sub-mm emission. Doing so yields m_AB=24.9 arcsec^-2 in F110W and m_AB=24.5 arcsec^-2 in F160W. Then, requiring an SN>4 per WFC3 pixel, leads to total required on-source times of 4000s in F110W and 4500s in F160W We arrange the observations so that the possibility of significant He contamination in the F110W exposures is minimized. In each orbit we observe with both F160W and F110W, "padding" the F110W observations with F160W observations so that the F110W observations do not occur at the start or end of the orbit. We also use SPARSE sampling so that the nucleus of the quasar cannot saturate. Since the submm structure is more than 0.5 arcsec from the quasar we do not request an observed PSF, but will instead construct a PSF from stars in the field, or use a Tinytim PSF. Using this strategy, the total on-source time is 4044s in F110W and 4888s in F160W. ------------------------------------------------------------------------------------ 15200( 3) - 06-Sep-2017 13:11:26 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 SDSSJ160705. GALAXY, HIGH REDSHIFT RA=16H07M5.1550S, J2000 Z = V = 18.93 15+533558.9 GALAXY, INTERACTING DEC=+53D35'58.58" 3.635288 GALAXY, PROTOGALAXY, QUASAR, ULTRALUMINOUS IR GAL Reference Frame: Other: SIMBAD Extended: YES Comments: This object was generated by the targetselector and retrieved from the SIMBAD database. ------------------------------------------------------------------------------------------------------------------------------------ 15200( 3) - 06-Sep-2017 13:11:26 - [ 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 0.572 Line_Spacing 0.365 Coordinate_Frame POS-TARG Pattern_Orient 18.528 Angle_Between_Sides 74.653 Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ 15200( 3) - 06-Sep-2017 13:11:26 - [ 5] Visit: 01 Visit Requirements: PCS MODE FINE; BETWEEN 02-SEP-2017:00:00:00 AND 21-NOV-2017:00:00:00; BETWEEN 18-DEC-2017:00:00:00 AND 30-SEP-2019:00:00:00 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 SDSSJ160705 WFC3/IR MULTIAC IR F110W NSAMP=15, SAMP-SEQ=SPARS50 1 DEF PATTERN 1 1-2; PAR 2 .15+533558. CUM (2811.754 WITH 1 9 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 ANY ACS/WFC ACCUM WFC F814W CR-SPLIT=NO, GAIN=2.0 1 530 S (2120 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 SDSSJ160705 WFC3/IR MULTIAC IR F160W NSAMP=15, SAMP-SEQ=SPARS50 1 DEF PATTERN 1 3-4; PAR 4 .15+533558. CUM (2811.754 WITH 3 9 S) ------------------------------------------------------------------------------------------------------------------------------------ 4 ANY ACS/WFC ACCUM WFC F814W CR-SPLIT=NO, GAIN=2.0 1 635 S (2540 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 | ------------------------------------------------------------------------------------------------------------------------------------ SDSSJ160705.15+5335 1 WFC3/IR MULTIAC IR F110W 1 none none none 1 N/A 58.9 CUM SDSSJ160705.15+5335 1 WFC3/IR MULTIAC IR F110W 2 none none none 1 N/A 58.9 CUM SDSSJ160705.15+5335 1 WFC3/IR MULTIAC IR F110W 3 none none none 1 N/A 58.9 CUM SDSSJ160705.15+5335 1 WFC3/IR MULTIAC IR F110W 4 none none none 1 N/A 58.9 CUM ANY 2 ACS/WFC ACCUM WFC F814W 1 none none none 1 N/A ANY 2 ACS/WFC ACCUM WFC F814W 2 none none none 1 N/A ANY 2 ACS/WFC ACCUM WFC F814W 3 none none none 1 N/A ANY 2 ACS/WFC ACCUM WFC F814W 4 none none none 1 N/A SDSSJ160705.15+5335 3 WFC3/IR MULTIAC IR F160W 1 none none none 2 N/A 58.9 CUM SDSSJ160705.15+5335 3 WFC3/IR MULTIAC IR F160W 2 none none none 2 N/A 58.9 CUM SDSSJ160705.15+5335 3 WFC3/IR MULTIAC IR F160W 3 none none none 2 N/A 58.9 CUM SDSSJ160705.15+5335 3 WFC3/IR MULTIAC IR F160W 4 none none none 2 N/A 58.9 CUM ANY 4 ACS/WFC ACCUM WFC F814W 1 none none none 2 N/A 15200( 3) - 06-Sep-2017 13:11:26 - [ 6] 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 | ------------------------------------------------------------------------------------------------------------------------------------ ANY 4 ACS/WFC ACCUM WFC F814W 2 none none none 2 N/A ANY 4 ACS/WFC ACCUM WFC F814W 3 none none none 2 N/A ANY 4 ACS/WFC ACCUM WFC F814W 4 none none none 2 N/A 15200( 3) - 06-Sep-2017 13:11:26 - [ 7] Visit: 02 Visit Requirements: PCS MODE FINE; BETWEEN 02-SEP-2017:00:00:00 AND 21-NOV-2017:00:00:00; BETWEEN 18-DEC-2017:00:00:00 AND 30-SEP-2019:00:00:00 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 SDSSJ160705 WFC3/IR MULTIAC IR F110W NSAMP=15, SAMP-SEQ=SPARS50 1 DEF PATTERN 1 1-2; PAR 2 .15+533558. CUM (2811.754 WITH 1 9 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 ANY ACS/WFC ACCUM WFC F814W CR-SPLIT=NO, GAIN=2.0 1 530 S (2120 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 SDSSJ160705 WFC3/IR MULTIAC IR F160W NSAMP=15, SAMP-SEQ=SPARS50 1 DEF PATTERN 1 3-4; PAR 4 .15+533558. CUM (2811.754 WITH 3 9 S) ------------------------------------------------------------------------------------------------------------------------------------ 4 ANY ACS/WFC ACCUM WFC F814W CR-SPLIT=NO, GAIN=2.0 1 635 S (2540 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 | ------------------------------------------------------------------------------------------------------------------------------------ SDSSJ160705.15+5335 1 WFC3/IR MULTIAC IR F110W 1 none none none 1 N/A 58.9 CUM SDSSJ160705.15+5335 1 WFC3/IR MULTIAC IR F110W 2 none none none 1 N/A 58.9 CUM SDSSJ160705.15+5335 1 WFC3/IR MULTIAC IR F110W 3 none none none 1 N/A 58.9 CUM SDSSJ160705.15+5335 1 WFC3/IR MULTIAC IR F110W 4 none none none 1 N/A 58.9 CUM ANY 2 ACS/WFC ACCUM WFC F814W 1 none none none 1 N/A ANY 2 ACS/WFC ACCUM WFC F814W 2 none none none 1 N/A ANY 2 ACS/WFC ACCUM WFC F814W 3 none none none 1 N/A ANY 2 ACS/WFC ACCUM WFC F814W 4 none none none 1 N/A SDSSJ160705.15+5335 3 WFC3/IR MULTIAC IR F160W 1 none none none 2 N/A 58.9 CUM SDSSJ160705.15+5335 3 WFC3/IR MULTIAC IR F160W 2 none none none 2 N/A 58.9 CUM SDSSJ160705.15+5335 3 WFC3/IR MULTIAC IR F160W 3 none none none 2 N/A 58.9 CUM SDSSJ160705.15+5335 3 WFC3/IR MULTIAC IR F160W 4 none none none 2 N/A 58.9 CUM ANY 4 ACS/WFC ACCUM WFC F814W 1 none none none 2 N/A 15200( 3) - 06-Sep-2017 13:11:26 - [ 8] 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 | ------------------------------------------------------------------------------------------------------------------------------------ ANY 4 ACS/WFC ACCUM WFC F814W 2 none none none 2 N/A ANY 4 ACS/WFC ACCUM WFC F814W 3 none none none 2 N/A ANY 4 ACS/WFC ACCUM WFC F814W 4 none none none 2 N/A 15200( 3) - 06-Sep-2017 13:11:26 - [ 9] Summary Form for Proposal 15200 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures IR, WFC ------------------------------------------------------------------------------------------------------------------------------------ Configurations ACS/WFC, WFC3/IR ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM, MULTIACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters CR-SPLIT=NO, GAIN=2.0, NSAMP=15, SAMP-SEQ=SPARS50 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements BETWEEN 02-SEP-2017:00:00:00 AND 21-NOV-2017:00:00:00, BETWEEN 18-DEC-2017:00:00:00 AND 30-SEP-2019:00:00:00, PAR 2 WITH 1, PAR 4 WITH 3, PATTERN 1 1-2, PATTERN 1 3-4, PCS MODE FINE ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F110W, F160W, F814W ------------------------------------------------------------------------------------------------------------------------------------ Target Names ANY, SDSSJ160705.15+533558.9 ------------------------------------------------------------------------------------------------------------------------------------