15410( 2) - 15-Dec-2017 20:28:37 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 15410 Version: 2 Check-in Time: 15-Dec-2017 20:28:37 STScI Edit Number: 0 Title The Nature of the Host Galaxies of Damped Lyman-alpha Absorbers at z~4 ------------------------------------------------------------------------------------ Type Cycle GO 25 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. Marcel Neeleman University of California - Santa Cruz Y CoI: Dr. Nissim Kanekar National Centre for Radio Astrophysics, N TIFR CoI: Dr. Jason X. Prochaska University of California - Santa Cruz N ------------------------------------------------------------------------------------ Abstract Absorption-selected galaxies, specifically those associated with damped Ly-alpha absorbers (DLAs), provide a unique opportunity to study the gas in 'typical' galaxies at high redshifts. We have recently used ALMA to detect the [CII] 158 micron line from four of five targeted DLAs at z > 4, and have also used the VLA to detect CO (2-1) emission from one of these systems, obtaining a large molecular gas mass. We propose to continue this successful ALMA+VLA project, by complementing the ALMA [CII] 158 micron observations with (1) a VLA Q-band search for CO(2-1) emission from the 3 remaining [CII] 158 micron detections at z~4.2-4.4, and (2) an HST-WFC3 imaging of the 4 DLA host galaxies with ALMA+VLA observations in the F160W filter. The VLA observations will yield molecular gas masses for the 3 galaxies, while the HST-WFC3 observations will measure the dust-unobscured star formation rates; the combination of ALMA, VLA and HST data will allow us to obtain the most complete picture of high-z DLA host galaxies to date, and to directly test whether such galaxies might have been missed in emission-selected samples due to dust obscuration. We request 35.75 hours of VLA Q-band time and 4 orbits of HST time. ------------------------------------------------------------------------------------ Observations Description ------------------------ We will image 4 galaxies associated with z~4 DLAs in the near-infrared with the F160W filter on the WFC3 camera. The four targets were selected from a sample of DLA host galaxies which have been observed with ALMA (see Neeleman et al. , 2017). The target galaxies all have been detected in [CII] 158 micron line emission, confirming their association with the DLAs (including redshift), and yielding solid measurements of the angular separation between the host galaxy and the quasar sightline. As this is a joint proposal with the VLA, we will also obtain information on the molecular content of the galaxy through the observation of the CO(2-1) emission line from the 4 galaxies associated with these DLAs. The primary goal of the HST observations is a measurement of the rest-frame NUV flux from the galaxies in order to determine the unobscured SFR. SFR estimates from the ALMA observations (i.e., from dust-processed light) are on average 20 Msun/year. One orbit with the WFC3/F160W camera/filter combination will yield a 3sigma detection limit of 26.5 AB, where we have assumed that the light is emitted from a centrally located source with a radius of 0.25''. This is 15410( 2) - 15-Dec-2017 20:28:37 - [ 2] consistent with the ALMA observations, which have synthesized beams of 0.5'' full width at half maximum, and only the highest star-forming galaxy is barely resolved. The proposed flux limit of 26.5 AB corresponds to a 3sigma SFR of 2 Msun/year (Kennicutt & Evans (2012)), and will allow us to determine the amount of dust extinction in these galaxies. In case of a detection, we will further be able to determine the extent of the emission, and compare this to the emission seen in [CII] and the possible CO molecular line emission. This allows us to ascertain if all of the emission is co-spatial or arises from different parts of the galaxy. We will apply four dither positions for each of the targets. This will provide sub-pixel sampling of the PSF, and due to the multiple non-destructive reads with WFC3/IR, is ample to remove cosmic rays and create clean images. ------------------------------------------------------------------------------------ 15410( 2) - 15-Dec-2017 20:28:37 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 J0834+2140 GALAXY, HIGH REDSHIFT RA=08H34M29.4500S, J2000 Z = V = 27 GALAXY DEC=+21D40'24.79" 4.3900 Reference Frame: ICRS Comments: V-magnitude is an estimate as no optical information is available for this galaxy ------------------------------------------------------------------------------------------------------------------------------------ 2 J1101+0531 GALAXY, HIGH REDSHIFT RA=11H01M34.3600S, J2000 Z = V = 27 GALAXY DEC=+05D31'34.12" 4.3446 Reference Frame: ICRS Comments: V-magnitude is an estimate as no optical information is available for this galaxy ------------------------------------------------------------------------------------------------------------------------------------ 3 J1443+2724 GALAXY, HIGH REDSHIFT RA=14H43M31.1700S, J2000 V = 27 GALAXY DEC=+27D24'36.73" Reference Frame: ICRS Comments: V-magnitude is an estimate as no optical information is available for this galaxy ------------------------------------------------------------------------------------------------------------------------------------ 4 J0817+1351 GALAXY, HIGH REDSHIFT RA=08H17M40.5300S, J2000 V = 27.0 GALAXY DEC=+13D51'34.60" Reference Frame: ICRS Comments: V-magnitude is an estimate as no optical information is available for this galaxy ------------------------------------------------------------------------------------------------------------------------------------ 15410( 2) - 15-Dec-2017 20:28:37 - [ 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 ------------------------------------------------------------------------------------------------------------------------------------ 15410( 2) - 15-Dec-2017 20:28:37 - [ 5] Visit: 01 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 J0834+2140 WFC3/IR MULTIAC IR F160W 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 | ------------------------------------------------------------------------------------------------------------------------------------ J0834+2140 1 WFC3/IR MULTIAC IR F160W 1 none none none 1 N/A CUM J0834+2140 1 WFC3/IR MULTIAC IR F160W 2 none none none 1 N/A CUM J0834+2140 1 WFC3/IR MULTIAC IR F160W 3 none none none 1 N/A CUM J0834+2140 1 WFC3/IR MULTIAC IR F160W 4 none none none 1 N/A CUM 15410( 2) - 15-Dec-2017 20:28:37 - [ 6] 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| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 J1101+0531 WFC3/IR MULTIAC IR F160W 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 | ------------------------------------------------------------------------------------------------------------------------------------ J1101+0531 1 WFC3/IR MULTIAC IR F160W 1 none none none 1 N/A CUM J1101+0531 1 WFC3/IR MULTIAC IR F160W 2 none none none 1 N/A CUM J1101+0531 1 WFC3/IR MULTIAC IR F160W 3 none none none 1 N/A CUM J1101+0531 1 WFC3/IR MULTIAC IR F160W 4 none none none 1 N/A CUM 15410( 2) - 15-Dec-2017 20:28:37 - [ 7] 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 J1443+2724 WFC3/IR MULTIAC IR F160W 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 | ------------------------------------------------------------------------------------------------------------------------------------ J1443+2724 1 WFC3/IR MULTIAC IR F160W 1 none none none 1 N/A CUM J1443+2724 1 WFC3/IR MULTIAC IR F160W 2 none none none 1 N/A CUM J1443+2724 1 WFC3/IR MULTIAC IR F160W 3 none none none 1 N/A CUM J1443+2724 1 WFC3/IR MULTIAC IR F160W 4 none none none 1 N/A CUM 15410( 2) - 15-Dec-2017 20:28:37 - [ 8] Visit: 04 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 J0817+1351 WFC3/IR MULTIAC IR F160W 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 | ------------------------------------------------------------------------------------------------------------------------------------ J0817+1351 1 WFC3/IR MULTIAC IR F160W 1 none none none 1 N/A CUM J0817+1351 1 WFC3/IR MULTIAC IR F160W 2 none none none 1 N/A CUM J0817+1351 1 WFC3/IR MULTIAC IR F160W 3 none none none 1 N/A CUM J0817+1351 1 WFC3/IR MULTIAC IR F160W 4 none none none 1 N/A CUM 15410( 2) - 15-Dec-2017 20:28:37 - [ 9] Summary Form for Proposal 15410 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures IR ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFC3/IR ------------------------------------------------------------------------------------------------------------------------------------ Opmodes MULTIACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters NSAMP=14, SAMP-SEQ=SPARS50 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements PATTERN 1 1 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F160W ------------------------------------------------------------------------------------------------------------------------------------ Target Names J0817+1351, J0834+2140, J1101+0531, J1443+2724 ------------------------------------------------------------------------------------------------------------------------------------