0 Assigned ID: 948 ----- Attempting Submission 1 (Fri Apr 10 22:28:30 GMT 2015) ----- 0 ----- Attempting Submission 1 (Sun Jul 12 10:07:46 GMT 2015) ----- Recent studies have used high spatial resolution HST observations of supernova (SN) sites to directly identify the progenitors of core-collapse SNe on pre-explosion images. These studies have set constraints about the nature of massive stars and their evolution just prior to their explosion as SNe. Now, at late-times when the SNe have faded sufficiently, it is possible to return to the sites of these core-collapse SNe to search for clues about the nature of their progenitors. We request time to conduct deep, late-time, high-resolution imaging with ACS WFC of the site of the core-collapse SN 2012ec. We aim to: 1) Confirm our original identification, made in pre-explosion HST images, by confirming that the progenitor is now missing; 2) Apply image subtraction techniques for this late-time imaging with our pre-explosion images to determine accurate photometry of the progenitor to constrain its temperature and luminosity; and 3) use the stellar population in the immediate vicinity of the SN to determine the reddening and extinction that affected the progenitor. HST provides the unique combination of high-resolution optical/IR imaging at very faint magnitudes that will facilitate this study. We require deep three colour observations of the site of SN 2012ec in the galaxy NGC 1084. The observations will use the ACS WFC, with a 1kx1k subarray (to minimise overheads due to readout time). We will use the F475W, F606W and F814W filters. For each filter we will use a four point box dither pattern, to aid the removal of hot pixels and cosmic rays and to provide improved sampling of the PSF. The coordinates for the target, SN 2012ec, were retrieved from the CfA SN list (http://www.cbat.eps.harvard.edu/lists/Supernovae.html). These observations are intended to reach limiting magnitudes of m_F435W = 27, m_F555W = 27 and m_F814W = 26.5 at 3sigma. HOT STARS 12 false false false false SUPPORTED EXT-STAR K III-I M III-I STAR FORMING REGION SUPERNOVA SUPERNOVA TYPE II NO This object was generated by the targetselector and retrieved from the SIMBAD database. J2000 J2000 ACS/WFC Imaging No No F475W ACS/WFC Imaging No No F606W ACS/WFC Imaging No No F814W POS-TARG DITHER 0.265 LINE 0.187 false false 69.05 4 20.67 ACS-WFC-DITHER-BOX 1 false 1436695343269 /Users/justyn/Documents/text/proposals/hst_cycle23/go/OP-cache/Phase2-iteration1-v01.xml The scheduling data was generated by CASM 23.2. CASM was run in Phase II mode. There is no particular urgency for these observations, but the later they occur the better (so we have provided a suggested timing constraint of after 1st March 2016). (Tic-Visit :proposal-id 14226 :visit-id "01" :proposal-version -1 :trans-version "20150609" :date "12-Jul-2015 11:02:22.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 2 :saa-model "27" :si-bright-earth-limb-angle 20.0 :data-volume 213328 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 14226 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 14226 :visit-id "01" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2877 :al-overhead-at-end 0 :internal-dur-at-end 0 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3213 :pcs-gap 0 ) (Tic-Orbit :proposal-id 14226 :visit-id "01" :orbit-number 2 :pcs-time 222 :si-vis-utilization 2989 :al-overhead-at-end 0 :internal-dur-at-end 270 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3213 :pcs-gap 0 ) true 2 0