Science Keywords: Select from 2 to 5 items. Science Keywords is a required field. 0 Assigned ID: 1611 ----- Attempting Submission 1 (Wed Nov 15 16:42:48 GMT 2017) ----- Joint NRAO 0 ----- Attempting Submission 1 (Wed Dec 13 20:12:31 GMT 2017) ----- Understanding the Origin of Large Gas Reservoirs in Recently-Quenched Galaxies The physical mechanisms that quench star formation, turning disky star-forming galaxies into quiescent elliptical galaxies, remain hotly debated. Post-starburst galaxies present a fascinating laboratory in which to study how star formation is suppressed, especially at z>~0.5 when these galaxies can be identified immediately after their primary star-forming epoch. We recently detected large molecular gas reservoirs in massive post-starburst galaxies at z~0.7 with ALMA-- much more gas than expected given their SFR. However, to fully interpret these remarkable ALMA results we must understand the roles of highly obscured star formation and merging in these galaxies. Here, we propose to use the VLA to obtain 1.4GHz-based SFRs for our three ALMA targets; these data are essential to determine whether these objects are truly as quiescent as they appear. Non-detections would prove that these objects are among the least efficient known star-formers. We also have hints that mergers may be important in quenching these galaxies, but existing imaging does not resolve the galaxies: we therefore propose to use complementary HST imaging to study the morphology of these galaxies and search for merger signatures. Obtaining both VLA and HST data will also allow us to place these galaxies on the classical Kennicutt-Schmidt relation. For each of three z~0.6 bright post-starburst galaxy targets (i_AB ~ 15) we will perform a one-orbit observation of about 50 minutes. Each integration will be divided into five on-source integrations, plus 10 minutes for acquisition and dithers. We will take four dithers using the WFC3-IR-DITHER-BOX in order to properly sample the PSF. To maximize our dynamic range, we will use STEP50 with NSAMP=15. We take an additional exposure using STEP50 and NSAMP=15 at our last dither position to fill the orbit. The 10.6 min of overheads are divided into 6 min of acquisition, 0.3 x 4 for dithers, and 0.8 min of readout per exposure. We will observe with the WFC3-IR/F110W filter. For the given exposure time, we will reach a surface brightness in F110W_AB of 25.9 (at 5sigma) in an aperture of 5 by 5 pixels. Given an average total magnitude of 19 and an approximate scale length of 0.4", we derive that we will observe the galaxies out to 3-4 scale lengths. With radial binning we will reach ~2 magnitudes deeper. Galaxies and the IGM 6 false false false false false false SUPPORTED GALAXY ELLIPTICAL LENTICULAR STARBURST UNDESIGNATED J2000 J2000 u_AB = 20.91 +/- 0.09, g_AB = 20.37 +/- 0.03, r_AB = 19.59 +/- 0.02, i_AB = 18.64 +/- 0.01, z_AB = 18.40 +/- 0.03 GALAXY ELLIPTICAL LENTICULAR STARBURST UNDESIGNATED J2000 J2000 u_AB = 21.99 +/- 0.19, g_AB = 20.75 +/- 0.03, r_AB = 19.38 +/- 0.02, i_AB = 18.54 +/- 0.01, z_AB = 18.25 +/- 0.03 GALAXY ELLIPTICAL LENTICULAR STARBURST UNDESIGNATED J2000 J2000 u_AB = 22.01 +/- 0.28, g_AB = 20.95 +/- 0.05, r_AB = 19.26 +/- 0.02, i_AB = 18.57 +/- 0.01, z_AB = 18.32 +/- 0.04 WFC3/IR Imaging No No F110W WFC3/IR Imaging No No F110W WFC3/IR Imaging No No F110W POS-TARG DITHER 1.420 LINE 0.919 false false 76.301 4 17.370 WFC3-IR-DITHER-BOX-MIN 1 false The scheduling data was generated by CASM 25.2. CASM was run in Phase II mode. (Tic-Visit :proposal-id 15436 :visit-id "01" :proposal-version -1 :trans-version "20171009" :date "12-Dec-2017 10:58:49.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "30" :si-bright-earth-limb-angle 20.0 :data-volume 1392704 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 15436 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 15436 :visit-id "01" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2787 :al-overhead-at-end 0 :internal-dur-at-end 538 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3216 :pcs-gap 0 ) true 1 0 The scheduling data was generated by CASM 25.2. CASM was run in Phase II mode. (Tic-Visit :proposal-id 15436 :visit-id "02" :proposal-version -1 :trans-version "20171009" :date "12-Dec-2017 10:44:40.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "30" :si-bright-earth-limb-angle 20.0 :data-volume 1392704 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 15436 :visit-id "02" :obset-id "02" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 15436 :visit-id "02" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2787 :al-overhead-at-end 0 :internal-dur-at-end 538 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3202 :pcs-gap 0 ) false 1 0 The scheduling data was generated by CASM 25.2. CASM was run in Phase II mode. (Tic-Visit :proposal-id 15436 :visit-id "03" :proposal-version -1 :trans-version "20171009" :date "12-Dec-2017 10:59:50.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "30" :si-bright-earth-limb-angle 20.0 :data-volume 1392704 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 15436 :visit-id "03" :obset-id "03" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 15436 :visit-id "03" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2787 :al-overhead-at-end 0 :internal-dur-at-end 538 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3202 :pcs-gap 0 ) true 1 0