0 Assigned ID: 509 ----- Attempting Submission 1 (Fri Apr 10 15:28:28 GMT 2015) ----- HST Phase I Proposal 509 (snprog.apt) successfully submitted. Receipt: # 509-1 ----- Attempting Submission 2 (Fri Apr 10 15:53:27 GMT 2015) ----- 0 ----- Attempting Submission 1 (Mon Jul 20 23:12:10 GMT 2015) ----- ----- Attempting Submission 2 (Wed Feb 10 21:49:39 GMT 2016) ----- ----- Attempting Submission 3 (Mon Mar 28 18:29:03 GMT 2016) ----- ----- Attempting Submission 4 (Fri Sep 23 15:55:18 GMT 2016) ----- ----- Attempting Submission 5 (Fri Sep 30 17:50:36 GMT 2016) ----- The Stellar Origins of Supernovae Supernovae (SNe) have a profound effect on galaxies, and have been used as precise cosmological probes, resulting in the Nobel-distinguished discovery of the accelerating Universe. They are clearly very important events deserving of intense study. Yet, even with over 6400 IAU-designated SNe, we know relatively little about the stars which give rise to these powerful explosions. The main limitation has been the lack of spatial resolution in pre-SN imaging data. However, our team has been at the vanguard of directly identifying SN progenitor stars in HST images. From this exciting line of study, we have learned that Type II-Plateau SNe appear to primarily arise from relatively low mass (8 to 20 Msun) red supergiants, leaving a puzzle as to what is happening to more massive stars. Additionally, evidence is accumulating that the progenitors of Type II-narrow SNe may be related to luminous blue variables. However, the nature of the progenitors of Type Ib/c SNe, a subset of which are associated with the amazing gamma-ray bursts, remains ambiguous. Furthermore, we remain in the continually embarrassing situation that we still do not yet know which progenitor systems explode as Type Ia SNe, which are being used for precision cosmology. In previous Cycles we have had great success with our approved ToO programs. As of this proposal deadline, we have had one trigger (SN 2014dt) completed so far and one pending (SN 2015G) with our Cycle 22 program. The compelling scientific questions lead us to continue this project to determine the identities of the progenitors of 4 SNe within, generally, about 20 Mpc, which we expect during Cycle 23, through ToO observations using WFC3/UVIS. We plan for four ToO triggers during Cycle 23. If we detect one or more candidate stellar objects within a 1-sigma positional uncertainty in ACS, WFPC2, or WFC3 pre-supernova archival image(s), we will request a trigger to pinpoint the location of the SN in the pre-SN images and attempt to confirm the progenitor candidate. Our plan is to image with WFC3/UVIS, to provide the highest possible spatial resolution. Our strategy, generally, is to acquire several short-exposure dithered images in V (F555W, 10-s) or I (F814W, 30-s), for the 3 core-collapse visits (which will likely best match with the available archival image data), and in U (F336W, 20-s) or B (F438W, 20-s) for a putative, nearby (<10 Mpc) SN Ia visit, since these SNe will likely be too bright in redder bands, but fade more rapidly in the blue. We will be using the UVIS2 1Kx1K subarray near amplifier C. Since the exposures are quite short, we will also be using post-flash with 12 e- for each exposure, in order to mitigate against CTE losses. The initial Phase II observations are meant to be representative of a typical trigger. Each of the four possible ToOs has an initial placeholder position of RA(J2000)=0, Dec(J2000)=0. We will likely request triggers when the SN is still fairly bright, depending on its age at discovery, but limit this, generally, to m >14 mag. We therefore may alter exposure times and bands, depending on the expected brightness of a given SN when it is scheduled and depending on the bands of the pre-SN images available for the SN site in the HST archive. This may also result in changes in the dither strategy for a given visit. The ToOs are not intended to be high-impact, and will be requested to occur after 2 to 3 weeks from discovery, so there should be no disruption of normal scheduling. RESOLVED STELLAR POPULATIONS 0 false false false false false false SUPPORTED EXT-STAR SUPERNOVA TYPE II J2000 J2000 EXT-STAR SUPERNOVA TYPE II J2000 J2000 EXT-STAR SUPERNOVA TYPE II J2000 J2000 EXT-STAR SUPERNOVA TYPE II J2000 J2000 WFC3/UVIS Imaging No No F555W WFC3/UVIS Imaging No No F555W WFC3/UVIS Imaging No No F555W WFC3/UVIS Imaging No No F336W POS-TARG DITHER 0.173 LINE 0.112 false false 81.785 4 23.884 WFC3-UVIS-DITHER-BOX 1 false POS-TARG DITHER 0.135 LINE false false 3 46.84 WFC3-UVIS-DITHER-LINE-3PT 2 false The scheduling data was generated by CASM 24.2. CASM was run in Phase II mode. 1456103938000 309.6306518108309 (Tic-Visit :proposal-id 14115 :visit-id "01" :proposal-version -1 :trans-version "20160601" :date "30-Sep-2016 10:49:33.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "29" :si-bright-earth-limb-angle 20.0 :data-volume 427792 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 14115 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 14115 :visit-id "01" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2797 :al-overhead-at-end 83 :internal-dur-at-end 504 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3307 :pcs-gap 0 ) true 1 0 Pending ToO activation. The scheduling data was generated by CASM 24.2. CASM was run in Phase II mode. 1460624871000 103.18966122332398 (Tic-Visit :proposal-id 14115 :visit-id "02" :proposal-version -1 :trans-version "20160601" :date "30-Sep-2016 10:49:37.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "29" :si-bright-earth-limb-angle 20.0 :data-volume 427792 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 14115 :visit-id "02" :obset-id "02" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 14115 :visit-id "02" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2479 :al-overhead-at-end 83 :internal-dur-at-end 504 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3307 :pcs-gap 0 ) true 1 0 The scheduling data was generated by CASM 24.2. CASM was run in Phase II mode. 1476059737000 346.7306490627095 (Tic-Visit :proposal-id 14115 :visit-id "03" :proposal-version -1 :trans-version "20160601" :date "30-Sep-2016 10:46:38.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "29" :si-bright-earth-limb-angle 20.0 :data-volume 427792 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 14115 :visit-id "03" :obset-id "03" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 14115 :visit-id "03" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2479 :al-overhead-at-end 83 :internal-dur-at-end 504 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3229 :pcs-gap 0 ) true 1 0 Pending ToO activation. The scheduling data was generated by CASM 24.2. CASM was run in Phase II mode. (Tic-Visit :proposal-id 14115 :visit-id "04" :proposal-version -1 :trans-version "20160601" :date "30-Sep-2016 10:25:11.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "29" :si-bright-earth-limb-angle 20.0 :data-volume 106960 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 14115 :visit-id "04" :obset-id "04" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 14115 :visit-id "04" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2910 :al-overhead-at-end 78 :internal-dur-at-end 153 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3245 :pcs-gap 0 ) true 1 0