17740( 2) - 16-Aug-2024 17:49:34 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 17740 Version: 2 Check-in Time: 16-Aug-2024 17:49:34 STScI Edit Number: 0 Title Gravitational-arc tomography of the circumgalactic medium at z~0.7: Identifying the host galaxies of three MgII absorbers ------------------------------------------------------------------------------------ Type Cycle GO 32 ------------------------------------------------------------------------------------ Investigators Contact? PI: Prof. Dawn K. Erb University of Wisconsin - Milwaukee Y CoI: Dr. Britt Lundgren University of North Carolina Asheville N CoI: Prof. Max Pettini University of Cambridge N CoI: Dr. Matthew Auger University of Cambridge N CoI: Lindsay Oldham Harvard University N CoI: Dr. Annalisa Citro University of Minnesota - Twin Cities N CoI: Dr. Bethan Lesley James Space Telescope Science Institute - ESA - N JWST CoI: Dr. Danielle Berg University of Texas at Austin N ------------------------------------------------------------------------------------ Abstract The dynamic circumgalactic medium (CGM) is the site of gas flows into, out of, and around galaxies, and thus plays a central role in regulating star formation over cosmic time. Many of its properties remain unconstrained, however, particularly on a spatially resolved basis. Extensive statistical studies of the gas around galaxies have been performed using the absorption it produces in background sources, usually quasars that probe a single line of sight. In particular, absorption from singly-ionized magnesium (MgII) has been shown to trace the outflow and accretion of cool, enriched gas surrounding galaxies. More recently, a handful of MgII-absorbing galaxies have been studied with gravitational-arc tomography, which uses the fortuitous alignment of an intermediate redshift galaxy and a background lensed arc to probe the gas around the foreground galaxy in unprecedented detail over tens of kpc. We here propose to use WFC3/IR grism spectroscopy to identify the galaxies responsible for spatially varying foreground MgII and FeII absorption observed at z~0.7-0.8 in Keck Cosmic Web Imager (KCWI) integral field spectroscopy of three gravitationally lensed galaxies. The proposed observations will provide spectroscopy at high spatial resolution of the entire field surrounding each arc, targeting H-alpha emission at the redshifts of the absorbers. Identification of the absorbing galaxies will enable measurement of the impact parameters of the absorption and the correlation of the strength, structure and kinematics of the absorption lines with the morphologies, star formation rates, and star formation rate surface densities of the absorbing galaxies. ------------------------------------------------------------------------------------ Observations Description ------------------------ The three target absorption systems are at z = 0.69, z = 0.83 and z = 0.65 for J1206+5142, J1514+3636 and J0918+5104 respectively, placing Halpha emission at 1.109, 1.201 and 1.083 um. We will therefore use the G102 grism with F098M direct images for the two lower redshift targets, J1206+5142 and J0918+5104, 17740( 2) - 16-Aug-2024 17:49:34 - [ 2] and the G141 grism with F140W direct images for J1514+3636. Orbits and exposures: ----------------- We observe each target for two orbits, and each visit consists of one orbit. In each orbit 2 dithered exposures with the grism will be obtained, along with short direct images taken at the same position, which are necessary for the wavelength calibration. We schedule the two orbits on each target as two different visits, with the roll angle of the second visit set to differ from that of the first visit by at least 20 degrees. We set ORIENT 20 TO 160 from the previous visit to the target, but ORIENT -20 to -160 is also acceptable. The purpose of using different roll angles for the two orbits is to improve our ability to account for contamination by overlapping spectra. This offset in the roll angle between visits to the same target will produce two sets of data with differing contamination properties, making the overall contamination for individual spectra easier to determine. We follow the simple pattern: direct, grism, offset, direct, grism Dithering strategy: --------------- We use POS-TARG offsets to enable rejection of hot/bad pixels and to improve sampling of the PSF. The pattern is: POS-TARG: (0, 0) (1.355, 0.424) pixels: (0, 0) (10.0, 3.5) This is a larger version of the standard WFC3-IR-DITHER-BOX-MIN pattern, which has only 1-2 pixel offsets between pointings. As some bad pixels come in clumps we prefer a slightly larger pattern. No attempt is made to dither over the "dead spot", as large dithers introduce large differential distortion. We use the same dither pattern for both visits to each field, since the differing orientations will ensure that spectra of the same objects fall on different pixels. Additional requirements: ------------------- For J1206+5142, we additionally specify an ORIENT range of 117 to 28 degrees for the first visit, based on avoiding spectral contamination from the lens and arc for the most likely host galaxy. We place no ORIENT constraints on the first visit for the other two targets. ------------------------------------------------------------------------------------ 17740( 2) - 16-Aug-2024 17:49:34 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 J1206+5142 GALAXY, GRAVITATIONAL RA=12H06M2.0180S, J2000 V = 21 LENS, HIGH REDSHIFT DEC=+51D42'34.00" GALAXY Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 2 J1514+3636 GALAXY, GRAVITATIONAL RA=15H14M22.2670S, J2000 V = 21 LENS, HIGH REDSHIFT DEC=+36D36'25.46" GALAXY Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 3 J0918+5104 GALAXY, GRAVITATIONAL RA=09H18M59.2810S, J2000 V = 21 LENS, HIGH REDSHIFT DEC=+51D04'53.07" GALAXY Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 17740( 2) - 16-Aug-2024 17:49:34 - [ 4] Visit: 01 Visit Requirements: ORIENT 117D TO 28 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 J1206+5142 WFC3/IR MULTIAC IR F098M NSAMP=6, SAMP-SEQ=SPARS50 1 DEF CUM (252.935 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 J1206+5142 WFC3/IR MULTIAC GRISM1024 G102 NSAMP=11, SAMP-SEQ=SPARS100 1 DEF SAME POS AS 1 CUM (1002.936 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 J1206+5142 WFC3/IR MULTIAC IR F098M NSAMP=6, SAMP-SEQ=SPARS50 1 DEF POS TARG 1.355, 0.424 CUM (252.935 S) ------------------------------------------------------------------------------------------------------------------------------------ 4 J1206+5142 WFC3/IR MULTIAC GRISM1024 G102 NSAMP=11, SAMP-SEQ=SPARS100 1 DEF SAME POS AS 3 CUM (1002.936 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 | ------------------------------------------------------------------------------------------------------------------------------------ J1206+5142 1 WFC3/IR MULTIAC IR F098M none none none none 1 N/A CUM J1206+5142 2 WFC3/IR MULTIAC GRISM102 G102 none none none none 1 N/A CUM 4 J1206+5142 3 WFC3/IR MULTIAC IR F098M none none none none 1 N/A CUM J1206+5142 4 WFC3/IR MULTIAC GRISM102 G102 none none none none 1 N/A CUM 4 17740( 2) - 16-Aug-2024 17:49:34 - [ 5] Visit: 02 Visit Requirements: ORIENT 20D TO 160D FROM 01 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 J1206+5142 WFC3/IR MULTIAC IR F098M NSAMP=6, SAMP-SEQ=SPARS50 1 DEF CUM (252.935 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 J1206+5142 WFC3/IR MULTIAC GRISM1024 G102 NSAMP=11, SAMP-SEQ=SPARS100 1 DEF SAME POS AS 1 CUM (1002.936 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 J1206+5142 WFC3/IR MULTIAC IR F098M NSAMP=6, SAMP-SEQ=SPARS50 1 DEF POS TARG 1.355, 0.424 CUM (252.935 S) ------------------------------------------------------------------------------------------------------------------------------------ 4 J1206+5142 WFC3/IR MULTIAC GRISM1024 G102 NSAMP=11, SAMP-SEQ=SPARS100 1 DEF SAME POS AS 3 CUM (1002.936 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 | ------------------------------------------------------------------------------------------------------------------------------------ J1206+5142 1 WFC3/IR MULTIAC IR F098M none none none none 1 N/A CUM J1206+5142 2 WFC3/IR MULTIAC GRISM102 G102 none none none none 1 N/A CUM 4 J1206+5142 3 WFC3/IR MULTIAC IR F098M none none none none 1 N/A CUM J1206+5142 4 WFC3/IR MULTIAC GRISM102 G102 none none none none 1 N/A CUM 4 17740( 2) - 16-Aug-2024 17:49:34 - [ 6] Visit: 03 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 J0918+5104 WFC3/IR MULTIAC IR F098M NSAMP=6, SAMP-SEQ=SPARS50 1 DEF CUM (252.935 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 J0918+5104 WFC3/IR MULTIAC GRISM1024 G102 NSAMP=11, SAMP-SEQ=SPARS100 1 DEF SAME POS AS 1 CUM (1002.936 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 J0918+5104 WFC3/IR MULTIAC IR F098M NSAMP=6, SAMP-SEQ=SPARS50 1 DEF POS TARG 1.355, 0.424 CUM (252.935 S) ------------------------------------------------------------------------------------------------------------------------------------ 4 J0918+5104 WFC3/IR MULTIAC GRISM1024 G102 NSAMP=11, SAMP-SEQ=SPARS100 1 DEF SAME POS AS 3 CUM (1002.936 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 | ------------------------------------------------------------------------------------------------------------------------------------ J0918+5104 1 WFC3/IR MULTIAC IR F098M none none none none 1 N/A CUM J0918+5104 2 WFC3/IR MULTIAC GRISM102 G102 none none none none 1 N/A CUM 4 J0918+5104 3 WFC3/IR MULTIAC IR F098M none none none none 1 N/A CUM J0918+5104 4 WFC3/IR MULTIAC GRISM102 G102 none none none none 1 N/A CUM 4 17740( 2) - 16-Aug-2024 17:49:34 - [ 7] Visit: 04 Visit Requirements: ORIENT 20D TO 160D FROM 03 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 J0918+5104 WFC3/IR MULTIAC IR F098M NSAMP=6, SAMP-SEQ=SPARS50 1 DEF CUM (252.935 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 J0918+5104 WFC3/IR MULTIAC GRISM1024 G102 NSAMP=11, SAMP-SEQ=SPARS100 1 DEF SAME POS AS 1 CUM (1002.936 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 J0918+5104 WFC3/IR MULTIAC IR F098M NSAMP=6, SAMP-SEQ=SPARS50 1 DEF POS TARG 1.355, 0.424 CUM (252.935 S) ------------------------------------------------------------------------------------------------------------------------------------ 4 J0918+5104 WFC3/IR MULTIAC GRISM1024 G102 NSAMP=11, SAMP-SEQ=SPARS100 1 DEF SAME POS AS 3 CUM (1002.936 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 | ------------------------------------------------------------------------------------------------------------------------------------ J0918+5104 1 WFC3/IR MULTIAC IR F098M none none none none 1 N/A CUM J0918+5104 2 WFC3/IR MULTIAC GRISM102 G102 none none none none 1 N/A CUM 4 J0918+5104 3 WFC3/IR MULTIAC IR F098M none none none none 1 N/A CUM J0918+5104 4 WFC3/IR MULTIAC GRISM102 G102 none none none none 1 N/A CUM 4 17740( 2) - 16-Aug-2024 17:49:34 - [ 8] Visit: 05 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 J1514+3636 WFC3/IR MULTIAC IR F140W NSAMP=5, SAMP-SEQ=SPARS50 1 DEF CUM (202.934 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 J1514+3636 WFC3/IR MULTIAC GRISM1024 G141 NSAMP=11, SAMP-SEQ=SPARS100 1 DEF SAME POS AS 1 CUM (1002.936 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 J1514+3636 WFC3/IR MULTIAC IR F140W NSAMP=5, SAMP-SEQ=SPARS50 1 DEF POS TARG 1.355, 0.424 CUM (202.934 S) ------------------------------------------------------------------------------------------------------------------------------------ 4 J1514+3636 WFC3/IR MULTIAC GRISM1024 G141 NSAMP=11, SAMP-SEQ=SPARS100 1 DEF SAME POS AS 3 CUM (1002.936 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 | ------------------------------------------------------------------------------------------------------------------------------------ J1514+3636 1 WFC3/IR MULTIAC IR F140W none none none none 1 N/A CUM J1514+3636 2 WFC3/IR MULTIAC GRISM102 G141 none none none none 1 N/A CUM 4 J1514+3636 3 WFC3/IR MULTIAC IR F140W none none none none 1 N/A CUM J1514+3636 4 WFC3/IR MULTIAC GRISM102 G141 none none none none 1 N/A CUM 4 17740( 2) - 16-Aug-2024 17:49:34 - [ 9] Visit: 06 Visit Requirements: ORIENT 20D TO 160D FROM 05 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 J1514+3636 WFC3/IR MULTIAC IR F140W NSAMP=5, SAMP-SEQ=SPARS50 1 DEF CUM (202.934 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 J1514+3636 WFC3/IR MULTIAC GRISM1024 G141 NSAMP=11, SAMP-SEQ=SPARS100 1 DEF SAME POS AS 1 CUM (1002.936 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 J1514+3636 WFC3/IR MULTIAC IR F140W NSAMP=5, SAMP-SEQ=SPARS50 1 DEF POS TARG 1.355, 0.424 CUM (202.934 S) ------------------------------------------------------------------------------------------------------------------------------------ 4 J1514+3636 WFC3/IR MULTIAC GRISM1024 G141 NSAMP=11, SAMP-SEQ=SPARS100 1 DEF SAME POS AS 3 CUM (1002.936 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 | ------------------------------------------------------------------------------------------------------------------------------------ J1514+3636 1 WFC3/IR MULTIAC IR F140W none none none none 1 N/A CUM J1514+3636 2 WFC3/IR MULTIAC GRISM102 G141 none none none none 1 N/A CUM 4 J1514+3636 3 WFC3/IR MULTIAC IR F140W none none none none 1 N/A CUM J1514+3636 4 WFC3/IR MULTIAC GRISM102 G141 none none none none 1 N/A CUM 4 17740( 2) - 16-Aug-2024 17:49:34 - [ 10] Summary Form for Proposal 17740 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures GRISM1024, IR ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFC3/IR ------------------------------------------------------------------------------------------------------------------------------------ Opmodes MULTIACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters NSAMP=11, NSAMP=5, NSAMP=6, SAMP-SEQ=SPARS100, SAMP-SEQ=SPARS50 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ORIENT 117D TO 28 D, ORIENT 20D TO 160D FROM 01, ORIENT 20D TO 160D FROM 03, ORIENT 20D TO 160D FROM 05, POS TARG 1.355, 0.424, SAME POS AS 1, SAME POS AS 3 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F098M, F140W, G102, G141 ------------------------------------------------------------------------------------------------------------------------------------ Target Names J0918+5104, J1206+5142, J1514+3636 ------------------------------------------------------------------------------------------------------------------------------------