13411( 3) - 19-Jun-2013 13:49:59 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 13411 Version: 3 Check-in Time: 19-Jun-2013 13:49:59 STScI Edit Number: 1 Title Dissecting the intensely star-forming clumps in a z ~ 2 Einstein Ring ------------------------------------------------------------------------------------ Type Cycle GO 21 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. Wiphu Rujopakarn University of Arizona Y CoI: Dr. George Rieke University of Arizona N CoI: Dr. Benjamin Weiner University of Arizona N CoI: Dr. Jane R. Rigby NASA Goddard Space Flight Center N CoI: Dr. Eiichi Egami University of Arizona N CoI: Dr. Johan Richard Centre de Recherche Astronomique de Lyon N CoI: Dr. Miroslava Dessauges-Zavadsky Observatoire de Geneve N CoI: Dr. Brenda L. Frye University of Arizona N CoI: Dr. Benjamin Clement University of Arizona N CoI: Gregory Walth University of Arizona N CoI: Ms. Kristina Erica Nyland New Mexico Institute of Mining and N Technology ------------------------------------------------------------------------------------ Abstract Clumps of star formation spreading widely in galactic disks are common features of star-forming galaxies at 1 < z < 3. This is the epoch when galaxy assembly activities peaked. These clumps could represent a pathway through which a majority of the stellar mass in the Universe was formed; understanding their formation and evolution is central to our understanding of galaxy evolution. However, the intensely star-forming clumps in disk galaxies at z ~ 2 have rarely been studied. Each of these clumps is forming stars in situ at a rate comparable to the most luminous merger-triggered starbursts in the local Universe. They are thus unique test cases to study the mechanism that drives intense star formation at z ~ 2. We propose WFC3 near-IR imaging and spatially-resolved spectroscopy of a gravitationally lensed, kinematically ordered, vigorously star-forming galaxy at z = 1.885 with physical resolutions up to 40 pc. This galaxy contains two luminous clumps that are forming stars at the rates of 100 solar mass/yr/clump. Spatially-resolved map of star formation from HST provides the most critical missing piece to interpret our existing observations of this galaxy in far-IR, CO emission lines, and radio continuum. We will probe the frontier research areas in z ~ 2 star formation, particularly the spatially-resolved star formation laws and dynamics of cold and ionized gases, which have never been probed at this spatial resolution. Our proposed observations will provide a benchmark against which to interpret the structures of vigorous star-forming clumps in general. This object can therefore have a unique impact on our understanding of the star-forming modes that dominate at z ~ 2. ------------------------------------------------------------------------------------ Observations Description ------------------------ We are observing a 2" Einstein ring image of a star-forming galaxy at z ~ 2 using WFC3 imaging and grism spectroscopy to obtain spatially-resolved color 13411( 3) - 19-Jun-2013 13:49:59 - [ 2] and H-beta/[OIII] variations, respectively. We set up this observation in two different ORIENT angles, each with 4.8 ks of G141 spectroscopy divided into 4 exposures (2 per orbit, 8 grism exposures total). Each G141 exposure is preceded by either F105W (6 exposures) or F140W (2 exposures) direct imaging (the target is fainter in F105W). We follow dithering strategy of program# 12177 (3D-HST, PI: van Dokkum), i.e., POS-TARG: (0, 0) (1.355, 0.424) (0.881, 1.212) (-0.474, 0.788) The narrow ORIENT requests (ORIENT-A = 237-249 deg, ORIENT-B = 165-185 deg) are to (1) avoid the 0th and 1st-order images from nearby bright objects, (2) avoid dispersing the elliptical lens galaxy onto the bright regions of the Einstein ring, and (3) avoid dispersing the bright regions of the Einstein ring onto themselves. Real Time Justification ----------------------- Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ 13411( 3) - 19-Jun-2013 13:49:59 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 A611RING GALAXY, EINSTEIN RING, RA=08H00M57.8600S, J2000 V = 24 F140W = 23.1 mag, F105W = 23.7 STARBURST, DEC=+36D14'13.35" mag ULTRALUMINOUS IR GAL Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 13411( 3) - 19-Jun-2013 13:49:59 - [ 4] Visit: 01 Visit Requirements: ORIENT 237D TO 249 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 A611RING WFC3/IR MULTIAC GRISM1024 F105W SAMP-SEQ=SPARS25, NSAMP=8 1 DEF POS TARG 0.0, 0.0; GS CUM (177.936 ACQ SCENARIO BASE1B3 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 A611RING WFC3/IR MULTIAC GRISM1024 G141 SAMP-SEQ=SPARS100, NSAMP=13 1 DEF SAME POS AS 1 CUM (1202.936 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 A611RING WFC3/IR MULTIAC GRISM1024 F105W SAMP-SEQ=SPARS25, NSAMP=9 1 DEF POS TARG 1.355, 0.424 CUM (202.936 S) ------------------------------------------------------------------------------------------------------------------------------------ 4 A611RING WFC3/IR MULTIAC GRISM1024 G141 SAMP-SEQ=SPARS100, NSAMP=13 1 DEF SAME POS AS 3 CUM (1202.936 S) ------------------------------------------------------------------------------------------------------------------------------------ 5 A611RING WFC3/IR MULTIAC GRISM1024 F140W SAMP-SEQ=SPARS25, NSAMP=10 1 DEF POS TARG 0.881, 1.212 CUM (227.937 S) ------------------------------------------------------------------------------------------------------------------------------------ 6 A611RING WFC3/IR MULTIAC GRISM1024 G141 SAMP-SEQ=SPARS100, NSAMP=13 1 DEF SAME POS AS 5 CUM (1202.936 S) ------------------------------------------------------------------------------------------------------------------------------------ 7 A611RING WFC3/IR MULTIAC GRISM1024 F140W SAMP-SEQ=SPARS25, NSAMP=11 1 DEF POS TARG -0.474, 0.788 CUM (252.937 S) ------------------------------------------------------------------------------------------------------------------------------------ 8 A611RING WFC3/IR MULTIAC GRISM1024 G141 SAMP-SEQ=SPARS100, NSAMP=13 1 DEF SAME POS AS 7 CUM (1202.936 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 | ------------------------------------------------------------------------------------------------------------------------------------ A611RING 1 WFC3/IR MULTIAC GRISM102 F105W none none none none 1 N/A CUM 4 A611RING 2 WFC3/IR MULTIAC GRISM102 G141 none none none none 1 N/A CUM 4 13411( 3) - 19-Jun-2013 13:49:59 - [ 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 | ------------------------------------------------------------------------------------------------------------------------------------ A611RING 3 WFC3/IR MULTIAC GRISM102 F105W none none none none 1 N/A CUM 4 A611RING 4 WFC3/IR MULTIAC GRISM102 G141 none none none none 1 N/A CUM 4 A611RING 5 WFC3/IR MULTIAC GRISM102 F140W none none none none 2 N/A CUM 4 A611RING 6 WFC3/IR MULTIAC GRISM102 G141 none none none none 2 N/A CUM 4 A611RING 7 WFC3/IR MULTIAC GRISM102 F140W none none none none 2 N/A CUM 4 A611RING 8 WFC3/IR MULTIAC GRISM102 G141 none none none none 2 N/A CUM 4 13411( 3) - 19-Jun-2013 13:49:59 - [ 6] Visit: 03 Visit Requirements: ORIENT 165D TO 185 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 A611RING WFC3/IR MULTIAC GRISM1024 F105W SAMP-SEQ=SPARS25, NSAMP=8 1 DEF POS TARG 0.0, 0.0 CUM (177.936 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 A611RING WFC3/IR MULTIAC GRISM1024 G141 SAMP-SEQ=SPARS100, NSAMP=13 1 DEF SAME POS AS 1 CUM (1202.936 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 A611RING WFC3/IR MULTIAC GRISM1024 F105W SAMP-SEQ=SPARS25, NSAMP=9 1 DEF POS TARG 1.355, 0.424 CUM (202.936 S) ------------------------------------------------------------------------------------------------------------------------------------ 4 A611RING WFC3/IR MULTIAC GRISM1024 G141 SAMP-SEQ=SPARS100, NSAMP=13 1 DEF SAME POS AS 3 CUM (1202.936 S) ------------------------------------------------------------------------------------------------------------------------------------ 5 A611RING WFC3/IR MULTIAC GRISM1024 F105W SAMP-SEQ=SPARS25, NSAMP=10 1 DEF POS TARG 0.881, 1.212 CUM (227.937 S) ------------------------------------------------------------------------------------------------------------------------------------ 6 A611RING WFC3/IR MULTIAC GRISM1024 G141 SAMP-SEQ=SPARS100, NSAMP=13 1 DEF SAME POS AS 5 CUM (1202.936 S) ------------------------------------------------------------------------------------------------------------------------------------ 7 A611RING WFC3/IR MULTIAC GRISM1024 F105W SAMP-SEQ=SPARS25, NSAMP=11 1 DEF POS TARG -0.474, 0.788 CUM (252.937 S) ------------------------------------------------------------------------------------------------------------------------------------ 8 A611RING WFC3/IR MULTIAC GRISM1024 G141 SAMP-SEQ=SPARS100, NSAMP=13 1 DEF SAME POS AS 7 CUM (1202.936 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 | ------------------------------------------------------------------------------------------------------------------------------------ A611RING 1 WFC3/IR MULTIAC GRISM102 F105W none none none none 1 N/A CUM 4 A611RING 2 WFC3/IR MULTIAC GRISM102 G141 none none none none 1 N/A CUM 4 13411( 3) - 19-Jun-2013 13:49:59 - [ 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 | ------------------------------------------------------------------------------------------------------------------------------------ A611RING 3 WFC3/IR MULTIAC GRISM102 F105W none none none none 1 N/A CUM 4 A611RING 4 WFC3/IR MULTIAC GRISM102 G141 none none none none 1 N/A CUM 4 A611RING 5 WFC3/IR MULTIAC GRISM102 F105W none none none none 2 N/A CUM 4 A611RING 6 WFC3/IR MULTIAC GRISM102 G141 none none none none 2 N/A CUM 4 A611RING 7 WFC3/IR MULTIAC GRISM102 F105W none none none none 2 N/A CUM 4 A611RING 8 WFC3/IR MULTIAC GRISM102 G141 none none none none 2 N/A CUM 4 13411( 3) - 19-Jun-2013 13:49:59 - [ 8] Summary Form for Proposal 13411 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures GRISM1024 ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFC3/IR ------------------------------------------------------------------------------------------------------------------------------------ Opmodes MULTIACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters NSAMP=10, NSAMP=11, NSAMP=13, NSAMP=8, NSAMP=9, SAMP-SEQ=SPARS100, SAMP-SEQ=SPARS25 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements GS ACQ SCENARIO BASE1B3, ORIENT 165D TO 185 D, ORIENT 237D TO 249 D, POS TARG -0.474, 0.788, POS TARG 0.0, 0.0, POS TARG 0.881, 1.212, POS TARG 1.355, 0.424, SAME POS AS 1, SAME POS AS 3, SAME POS AS 5, SAME POS AS 7 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F105W, F140W, G141 ------------------------------------------------------------------------------------------------------------------------------------ Target Names A611RING ------------------------------------------------------------------------------------------------------------------------------------