13045( 4) - 06-Aug-2012 15:58:04 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 13045 Version: 4 Check-in Time: 06-Aug-2012 15:58:04 STScI Edit Number: 0 Title The Nature and Environment of a Luminous Starburst Galaxy During the Era of Reionization ------------------------------------------------------------------------------------ Type Cycle GO 20 ------------------------------------------------------------------------------------ Investigators Contact? PI: Prof. Asantha Roshan Cooray University of California - Irvine Y CoI: Dr. Julie Wardlow University of California - Irvine N CoI: Dr. Hai Fu University of California - Irvine N CoI: Dr. Dominik A. Riechers California Institute of Technology N CoI: Dr. Seb Oliver University of Sussex N CoI: Dr. Ismael Perez-Fournon Instituto de Astrofisica de Canarias N CoI: Dr. David Clements Imperial College of Science Technology and N Medicine CoI: Dr. Joaquin Vieira California Institute of Technology N CoI: Dr. Duncan Farrah University of Sussex N CoI: Dr. Lingyu Wang University of Sussex N CoI: Dr. Caitlin M. Casey University of Hawaii N CoI: Dr. Alexander Conley University of Colorado at Boulder N CoI: Prof. Scott C. Chapman University of Cambridge N CoI: Dr. Carrie Bridge California Institute of Technology N CoI: Prof. Douglas Scott University of British Columbia N CoI: Prof. Mark Halpern University of British Columbia N CoI: Dr. Georgios Magdis University of Oxford N ------------------------------------------------------------------------------------ Abstract We propose HST/WFC3 and ACS observations in 5 bands to characterize the nature and the environment of the most distant sub-mm galaxy (SMG) known today, FLS3, at a redshift of 6.337. The galaxy was discovered in Herschel-HerMES with redshift measured from mm-wave spectroscopy. It is IR luminous (3x10^13 L_sun), gas rich (10^11 M_sun), dusty and star-bursting. Deep optical and K-band ground-based imaging showed a near-by galaxy at 0.5 arcsecond from FLS3 with a measured redshift of 2.1. HST resolution imaging are needed to properly separate the two galaxies and constrain a lensing magnification of FLS3, if any. Previously known z < 4 SMGs are in dense proto-cluster environments. The discovery of FLS3 suggests that it may also be in a proto-cluster. The HST imaging is also aimed at identifying Lyman dropout samples at z~6.4 associated with FLS3. With proposed data we will complete the SED and determine the stellar mass of FLS at better than 30%, a key quantity needed to understand the nature of FLS3 when combined with its star-formation rate. We will also measure the UV slope-SFR relation for a galaxy at z > 6 and compare to measurements at z~0 to 3. With dropouts we will establish the presence of a proto-cluster and establish the dark matter halo mass scale of FLS3, a key ingredient needed to connect its evolution with massive elliptical and other galaxies seen today. ------------------------------------------------------------------------------------ Observations Description ------------------------ 13045( 4) - 06-Aug-2012 15:58:04 - [ 2] The program is related to a detection and characterization of a extremely luminous and massive dusty, starburst galaxy (hereafter FLS3) found with Herschel at z=6.34, during the epoch of reionization, and its environment. The galaxy is detected in a deep LGS-AO image with KeckII/NIRC2 in the K-band with a AB magnitude of 23.5. The most basic goals of this program involving deep WFC3 and ACS observations of FLS3 are (i) determine the rest-frame UV SED, (ii) determine the location and size of the foreground galaxy at 0.500 away for a lens model, and (iii) identify other z =6.3 galaxies to determine the FLS3 environment and estimate the proto-cluster, if there is one associated with FLS3. To measure stellar mass and other properties of FLS3 we make use of WFC3/F160W, F125W, and F105W filters. ACS/F814W observations are needed to look for z=6 dropouts and to characterize the foreground lensing galaxy. We have used the on-line calculator to estimate the exposure time necessary to detect the background source with a signal-to-noise ratio (SNR) >10 in the WFC3 bands. The expected depths are obtained after scaling a range of SED templates to the K-band detection. These SEDs are appropriate for dusty starbursts and range from Arp220 to the average sub-mm galaxy SED at z of 2 to 3. We take the lowest flux density expected and require 10 sigma detections. The total of 6 HST orbits are distributed to 3 WFC3 bands and 1 ACS/F814W band. The ACS band in the optical allow a precise detection of the nearby z=2.1 galaxy about 0.5 arcseconds away from FLS3; at the shortest optical band, FLS3 is a dropout and we can measure the size and mass of the foreground galaxy accurately for a precise lensing model. A quantification of the lensing magnification is one of the goals of the approved HST program. The immediate environment of FLS3 will be characterized with a combination of F814W, F105W and F125W images. The extended environment of FLS3, overlapping with two other sources seen within 3 to 6 arcminutes from JCMT/SCUBA2 will be imaged with coordinated-parallel observations using ACS/F814W taken over 4 orbits. Real Time Justification ----------------------- To cover the interesting sub-mm/mm SCUBA2 detected targets within 3 to 6 arcminutes of FLS3 we request coordinated-parallel observations that involved WFC3 and ACS over 4 orbits. These observations require the orientation to be 10 and 120 degrees to maximize the ACS coverage of the intersting sources. The two orbits with ACS/F14W imaging that is mosacing the region around FLS3 also require a range of possible orientations. They range from 60 to 160 degrees and 240 to 340 degrees. Calibration Justification ------------------------- 13045( 4) - 06-Aug-2012 15:58:04 - [ 3] Additional Comments ------------------- ------------------------------------------------------------------------------------ 13045( 4) - 06-Aug-2012 15:58:04 - [ 4] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 HERMES-FLS03 GALAXY, HIGH REDSHIFT RA=17H06M47.7840S +/- 0.1", J2000 V = 29 +/- 0.1 K-band (2.146 microns) GALAXY, PROTOGALAXY DEC=+58D46'23.52" +/- 0.1" 1.46 muJy (23.5 AB) Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 13045( 4) - 06-Aug-2012 15:58:04 - [ 5] 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 ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 2 Primary_Pattern Secondary_Pattern Pattern_Type ACS-WFC-MOSAIC-LINE ACS-WFC-DITHER-LINE Pattern_Purpose MOSAIC DITHER Number_Of_Points 2 2 Point_Spacing 45.00 3.011 Line_Spacing Coordinate_Frame POS-TARG POS-TARG Pattern_Orient 90.0 85.28 Angle_Between_Sides Center_Pattern NO NO ------------------------------------------------------------------------------------------------------------------------------------ 13045( 4) - 06-Aug-2012 15:58:04 - [ 6] Visit: 01 Visit Requirements: ORIENT 10D TO 150 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 HERMES-FLS0 WFC3/IR MULTIAC IR F160W SAMP-SEQ=SPARS100, NSAMP=8 1 DEF PATTERN 1 1-9; PAR 5-9 3 CUM WITH 1-4 ------------------------------------------------------------------------------------------------------------------------------------ 2 HERMES-FLS0 WFC3/IR MULTIAC IR F125W SAMP-SEQ=SPARS100, NSAMP=12 1 DEF 3 CUM ------------------------------------------------------------------------------------------------------------------------------------ 3 HERMES-FLS0 WFC3/IR MULTIAC IR F105W SAMP-SEQ=SPARS100, NSAMP=10 1 DEF 3 CUM ------------------------------------------------------------------------------------------------------------------------------------ 4 HERMES-FLS0 WFC3/IR MULTIAC IR F105W SAMP-SEQ=SPARS25, NSAMP=14 1 DEF 3 CUM ------------------------------------------------------------------------------------------------------------------------------------ 5 HERMES-FLS0 ACS/WFC ACCUM WFC F814W 1 600 S 3 ------------------------------------------------------------------------------------------------------------------------------------ 6 HERMES-FLS0 ACS/WFC ACCUM WFC F814W 1 535 S 3 ------------------------------------------------------------------------------------------------------------------------------------ 7 HERMES-FLS0 ACS/WFC ACCUM WFC F814W 1 400 S 3 ------------------------------------------------------------------------------------------------------------------------------------ 8 HERMES-FLS0 ACS/WFC ACCUM WFC F625W 1 400 S 3 ------------------------------------------------------------------------------------------------------------------------------------ 9 HERMES-FLS0 ACS/WFC ACCUM WFC F625W 1 400 S 3 ------------------------------------------------------------------------------------------------------------------------------------ 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 | ------------------------------------------------------------------------------------------------------------------------------------ HERMES-FLS03 1 WFC3/IR MULTIAC IR F160W 1 none none none 1 N/A CUM HERMES-FLS03 1 WFC3/IR MULTIAC IR F160W 2 none none none 2 N/A CUM HERMES-FLS03 1 WFC3/IR MULTIAC IR F160W 3 none none none 3 N/A CUM HERMES-FLS03 1 WFC3/IR MULTIAC IR F160W 4 none none none 4 N/A CUM 13045( 4) - 06-Aug-2012 15:58:04 - [ 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 | ------------------------------------------------------------------------------------------------------------------------------------ HERMES-FLS03 2 WFC3/IR MULTIAC IR F125W 1 none none none 1 N/A CUM HERMES-FLS03 2 WFC3/IR MULTIAC IR F125W 2 none none none 2 N/A CUM HERMES-FLS03 2 WFC3/IR MULTIAC IR F125W 3 none none none 3 N/A CUM HERMES-FLS03 2 WFC3/IR MULTIAC IR F125W 4 none none none 4 N/A CUM HERMES-FLS03 3 WFC3/IR MULTIAC IR F105W 1 none none none 1 N/A CUM HERMES-FLS03 3 WFC3/IR MULTIAC IR F105W 2 none none none 2 N/A CUM HERMES-FLS03 3 WFC3/IR MULTIAC IR F105W 3 none none none 3 N/A CUM HERMES-FLS03 3 WFC3/IR MULTIAC IR F105W 4 none none none 4 N/A CUM HERMES-FLS03 4 WFC3/IR MULTIAC IR F105W 1 none none none 1 N/A CUM HERMES-FLS03 4 WFC3/IR MULTIAC IR F105W 2 none none none 2 N/A CUM HERMES-FLS03 4 WFC3/IR MULTIAC IR F105W 3 none none none 3 N/A CUM HERMES-FLS03 4 WFC3/IR MULTIAC IR F105W 4 none none none 4 N/A CUM HERMES-FLS03 5 ACS/WFC ACCUM WFC F814W 1 none none none 1 N/A HERMES-FLS03 5 ACS/WFC ACCUM WFC F814W 2 none none none 2 N/A HERMES-FLS03 5 ACS/WFC ACCUM WFC F814W 3 none none none 3 N/A HERMES-FLS03 5 ACS/WFC ACCUM WFC F814W 4 none none none 4 N/A HERMES-FLS03 6 ACS/WFC ACCUM WFC F814W 1 none none none 1 N/A HERMES-FLS03 6 ACS/WFC ACCUM WFC F814W 2 none none none 2 N/A HERMES-FLS03 6 ACS/WFC ACCUM WFC F814W 3 none none none 3 N/A HERMES-FLS03 6 ACS/WFC ACCUM WFC F814W 4 none none none 4 N/A HERMES-FLS03 7 ACS/WFC ACCUM WFC F814W 1 none none none 1 N/A HERMES-FLS03 7 ACS/WFC ACCUM WFC F814W 2 none none none 2 N/A HERMES-FLS03 7 ACS/WFC ACCUM WFC F814W 3 none none none 3 N/A HERMES-FLS03 7 ACS/WFC ACCUM WFC F814W 4 none none none 4 N/A HERMES-FLS03 8 ACS/WFC ACCUM WFC F625W 1 none none none 1 N/A HERMES-FLS03 8 ACS/WFC ACCUM WFC F625W 2 none none none 2 N/A HERMES-FLS03 8 ACS/WFC ACCUM WFC F625W 3 none none none 3 N/A HERMES-FLS03 8 ACS/WFC ACCUM WFC F625W 4 none none none 4 N/A HERMES-FLS03 9 ACS/WFC ACCUM WFC F625W 1 none none none 1 N/A HERMES-FLS03 9 ACS/WFC ACCUM WFC F625W 2 none none none 2 N/A HERMES-FLS03 9 ACS/WFC ACCUM WFC F625W 3 none none none 3 N/A HERMES-FLS03 9 ACS/WFC ACCUM WFC F625W 4 none none none 4 N/A 13045( 4) - 06-Aug-2012 15:58:04 - [ 8] Visit: 02 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| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 HERMES-FLS0 ACS/WFC ACCUM WFC F814W 1 562 S PATTERN 2 1-2 3 ------------------------------------------------------------------------------------------------------------------------------------ 2 HERMES-FLS0 ACS/WFC ACCUM WFC F625W 1 616 S 3 ------------------------------------------------------------------------------------------------------------------------------------ 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 | ------------------------------------------------------------------------------------------------------------------------------------ HERMES-FLS03 1 ACS/WFC ACCUM WFC F814W 1 1 none none 1 N/A HERMES-FLS03 1 ACS/WFC ACCUM WFC F814W 1 2 none none 1 N/A HERMES-FLS03 1 ACS/WFC ACCUM WFC F814W 2 1 none none 2 N/A HERMES-FLS03 1 ACS/WFC ACCUM WFC F814W 2 2 none none 2 N/A HERMES-FLS03 2 ACS/WFC ACCUM WFC F625W 1 1 none none 1 N/A HERMES-FLS03 2 ACS/WFC ACCUM WFC F625W 1 2 none none 1 N/A HERMES-FLS03 2 ACS/WFC ACCUM WFC F625W 2 1 none none 2 N/A HERMES-FLS03 2 ACS/WFC ACCUM WFC F625W 2 2 none none 2 N/A 13045( 4) - 06-Aug-2012 15:58:04 - [ 9] Summary Form for Proposal 13045 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures IR, WFC ------------------------------------------------------------------------------------------------------------------------------------ Configurations ACS/WFC, WFC3/IR ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM, MULTIACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters NSAMP=10, NSAMP=12, NSAMP=14, NSAMP=8, SAMP-SEQ=SPARS100, SAMP-SEQ=SPARS25 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ORIENT 10D TO 150 D, PAR 5-9 WITH 1-4, PATTERN 1 1-9, PATTERN 2 1-2 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F105W, F125W, F160W, F625W, F814W ------------------------------------------------------------------------------------------------------------------------------------ Target Names HERMES-FLS03 ------------------------------------------------------------------------------------------------------------------------------------