13392( 3) - 25-Jun-2013 10:30:46 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 13392 Version: 3 Check-in Time: 25-Jun-2013 10:30:46 STScI Edit Number: 0 Title Six in One Blow: Reconstructing the Circumstellar Environments of Supernovae in NGC 6946 with Light Echoes ------------------------------------------------------------------------------------ Type Cycle GO 21 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. Ben E. Sugerman Goucher College Y CoI: Dr. Jennifer Andrews University of Massachusetts - Amherst N CoI: Prof. Michael J. Barlow University College London N CoI: Dr. Geoffrey C. Clayton Louisiana State University and A & M N College CoI: Prof. Barbara Ercolano Universitats-Sternwarte Munchen N CoI: Dr. Joseph S. Gallagher University of Cincinnati-Raymond Walters N College CoI: Dr. Mikako Matsuura University College London N CoI: Dr. Margaret Meixner The Johns Hopkins University N CoI: Dr. Masaaki Otsuka Academia Sinica, Institute of Astronomy N and Astrophysics CoI: Prof. Nino Panagia Space Telescope Science Institute N CoI: Dr. Roger Wesson European Southern Observatory (ESO) N ------------------------------------------------------------------------------------ Abstract Reconstructing the circumstellar (CS) environment around a supernova (SN) is critical to studying the evolution and mass-loss mechanisms of massive stars, and in establishing the extent to which SNe and their progenitors contribute to the dust found in the early universe. Over the last decade, we have been performing all of these studies through imaging analyses and radiative-transfer modeling of HST optical and Spitzer mid-IR observations of the three SNe 1980K, 2002hh, and 2004et (all within "The Fireworks Galaxy" NGC 6946). These SNe all show evidence of optical and thermal echoes (see below) off of CS material. For each object, a variety of actual CS geometries fit the data equally well, since we have no recent optical images to disentangle important ambiguities in our analyses. Using 5 orbits of HST WFC3/UVIS and 1.6 hours of Spitzer, we propose to image these 3 SNe, which will provide crucial late-time data needed to complete our light-echo modeling. We will also attempt to recover the historic SNe 1917A and 1969P, and will continue our studies of the SN-imposter 2008S, all of which are in the same fields of view. Light echoes are one of the most powerful and efficient means to directly probe of the structure and composition of dust in CS environments, since echoes provide exact three-dimensional positions of dust while constraining its density, grain-size and chemical make-up. However, echoes pass through a given point only once, and since potential data are permanently lost for each epoch that echoes are not observed, most of the science we propose cannot be achieved if these observations are not taken this cycle. ------------------------------------------------------------------------------------ Observations Description ------------------------ 13392( 3) - 25-Jun-2013 10:30:46 - [ 2] This Phase 2 sequence is intended to image SNe 1980K and 2004et in one pointing, and SNe 1917A, 1969P, 2002hh, and 2008S in another pointing. The first pointing can image both targets using the UVIS1 chip and therefore has no restrictions on roll angle, however the second pointing requires that the full array be used, which eliminates roll angles 25-45 and 205-225 degrees. These restrictions have been coded into the visit roll-angle requirements. Also, please note that these HST observations must occur within 1 month of approved Spitzer observations of the same field. Given the restrictions on roll angle, and the fact that this field will be viewed by another Spitzer proposal in mid-to-late 2013, the best window for HST observations is 17 Feb 2014 to 7 Mar 2014. Each target needs to be imaged in a four-point sub-pixel dither pattern so that higher spatial resolution can be gained using drizzling. Each target requires exposure times of at least 1600 sec in F606W and F814W, and 2400 sec in F438W. We have allowed APT to resize the exposures to fill each of the 5 allotted orbits, giving slightly-higher observing times for each filter. Note that although these exposure times are much longer than strictly needed to reach S/N = 10 for a V = 25 point-source (roughly the level of our faintest targets), our previous programs have clearly demonstrated that these longer exposures dramatically reduce background noise, which is crucial when probing for very faint echoes or marginally-resolved sources. Real Time Justification ----------------------- Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ 13392( 3) - 25-Jun-2013 10:30:46 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 SN-2002HH-FI EXT-MEDIUM, EJECTA, RA=20H34M44.8078S +/- 0.1", J2000 V = 20 ELD REFLECTION NEBULA, SNR, DEC=+60D06'38.34" +/- 0.1" WIND Reference Frame: ICRS Comments: This object was generated by the targetselector and retrieved from the SIMBAD database. ------------------------------------------------------------------------------------------------------------------------------------ 2 SN-2004ET-FI EXT-MEDIUM, EJECTA, RA=20H35M27.8827S +/- 0.1", J2000 V = 20 ELD REFLECTION NEBULA, SNR, DEC=+60D06'50.97" +/- 0.1" WIND Reference Frame: ICRS Comments: This object was generated by the targetselector and retrieved from the SIMBAD database. ------------------------------------------------------------------------------------------------------------------------------------ 13392( 3) - 25-Jun-2013 10:30:46 - [ 4] Patterns ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 1 Primary_Pattern Secondary_Pattern Pattern_Type WFC3-UVIS-DITHER-BOX Pattern_Purpose DITHER Number_Of_Points 4 Point_Spacing 0.173 Line_Spacing 0.112 Coordinate_Frame POS-TARG Pattern_Orient 23.884 Angle_Between_Sides 81.785 Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ 13392( 3) - 25-Jun-2013 10:30:46 - [ 5] Visit: 01 Visit Requirements: ORIENT 45D TO 205 D; ORIENT 225D TO 25 D; BETWEEN 17-FEB-2014:00:00:00 AND 07-MAR-2014:00:00:00 On Hold Comments: Additional Comments: This proposal included 1.6 hours of Spitzer time to image the same fields with IRAC bands 1-2 (PID 10002). The Spitzer observation needs to happen within 1 month of the HST observation, and preferably as close as possible. The Spitzer visibility window is 02 Aug 2013 to 04 Apr 2014. Given the restrictions on roll angle, and the fact that this field will be viewed by another Spitzer proposal in mid-to-late 2013, the best window for HST observations is 17 Feb 2014 to 7 Mar 2014. We have put this in as a timing constraint in this proposal and the coordinated Spitzer AORs. 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 SN-2004ET-F WFC3/UVI ACCUM UVIS1 F438W FLASH=8 1 692 S PATTERN 1 1 IELD S (2768 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 SN-2004ET-F WFC3/UVI ACCUM UVIS1 F606W 1 436 S PATTERN 1 2 IELD S (1744 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 SN-2004ET-F WFC3/UVI ACCUM UVIS1 F814W 1 436 S PATTERN 1 3 IELD S (1744 S) ------------------------------------------------------------------------------------------------------------------------------------ 4 SN-2002HH-F WFC3/UVI ACCUM UVIS-CENT F814W 1 460 S PATTERN 1 4 IELD S ER (1840 S) ------------------------------------------------------------------------------------------------------------------------------------ 5 SN-2002HH-F WFC3/UVI ACCUM UVIS-CENT F606W 1 550 S PATTERN 1 5 IELD S ER (2200 S) ------------------------------------------------------------------------------------------------------------------------------------ 6 SN-2002HH-F WFC3/UVI ACCUM UVIS-CENT F438W FLASH=8 1 719 S PATTERN 1 6 IELD S ER (2876 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 | ------------------------------------------------------------------------------------------------------------------------------------ SN-2004ET-FIELD 1 WFC3/UVI ACCUM UVIS1 F438W 1 none none none 1 N/A S SN-2004ET-FIELD 1 WFC3/UVI ACCUM UVIS1 F438W 2 none none none 1 N/A S SN-2004ET-FIELD 1 WFC3/UVI ACCUM UVIS1 F438W 3 none none none 1 N/A S SN-2004ET-FIELD 1 WFC3/UVI ACCUM UVIS1 F438W 4 none none none 1 N/A S SN-2004ET-FIELD 2 WFC3/UVI ACCUM UVIS1 F606W 1 none none none 2 N/A S 13392( 3) - 25-Jun-2013 10:30:46 - [ 6] 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 | ------------------------------------------------------------------------------------------------------------------------------------ SN-2004ET-FIELD 2 WFC3/UVI ACCUM UVIS1 F606W 2 none none none 2 N/A S SN-2004ET-FIELD 2 WFC3/UVI ACCUM UVIS1 F606W 3 none none none 2 N/A S SN-2004ET-FIELD 2 WFC3/UVI ACCUM UVIS1 F606W 4 none none none 2 N/A S SN-2004ET-FIELD 3 WFC3/UVI ACCUM UVIS1 F814W 1 none none none 2 N/A S SN-2004ET-FIELD 3 WFC3/UVI ACCUM UVIS1 F814W 2 none none none 2 N/A S SN-2004ET-FIELD 3 WFC3/UVI ACCUM UVIS1 F814W 3 none none none 3 N/A S SN-2004ET-FIELD 3 WFC3/UVI ACCUM UVIS1 F814W 4 none none none 3 N/A S SN-2002HH-FIELD 4 WFC3/UVI ACCUM UVIS-CEN F814W 1 none none none 3 N/A S TER SN-2002HH-FIELD 4 WFC3/UVI ACCUM UVIS-CEN F814W 2 none none none 3 N/A S TER SN-2002HH-FIELD 4 WFC3/UVI ACCUM UVIS-CEN F814W 3 none none none 3 N/A S TER SN-2002HH-FIELD 4 WFC3/UVI ACCUM UVIS-CEN F814W 4 none none none 4 N/A S TER SN-2002HH-FIELD 5 WFC3/UVI ACCUM UVIS-CEN F606W 1 none none none 4 N/A S TER SN-2002HH-FIELD 5 WFC3/UVI ACCUM UVIS-CEN F606W 2 none none none 4 N/A S TER SN-2002HH-FIELD 5 WFC3/UVI ACCUM UVIS-CEN F606W 3 none none none 4 N/A S TER SN-2002HH-FIELD 5 WFC3/UVI ACCUM UVIS-CEN F606W 4 none none none 4 N/A S TER SN-2002HH-FIELD 6 WFC3/UVI ACCUM UVIS-CEN F438W 1 none none none 5 N/A S TER SN-2002HH-FIELD 6 WFC3/UVI ACCUM UVIS-CEN F438W 2 none none none 5 N/A S TER SN-2002HH-FIELD 6 WFC3/UVI ACCUM UVIS-CEN F438W 3 none none none 5 N/A S TER SN-2002HH-FIELD 6 WFC3/UVI ACCUM UVIS-CEN F438W 4 none none none 5 N/A S TER 13392( 3) - 25-Jun-2013 10:30:46 - [ 7] Summary Form for Proposal 13392 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures UVIS-CENTER, UVIS1 ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFC3/UVIS ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters FLASH=8 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements BETWEEN 17-FEB-2014:00:00:00 AND 07-MAR-2014:00:00:00, ORIENT 225D TO 25 D, ORIENT 45D TO 205 D, PATTERN 1 1, PATTERN 1 2, PATTERN 1 3, PATTERN 1 4, PATTERN 1 5, PATTERN 1 6 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F438W, F606W, F814W ------------------------------------------------------------------------------------------------------------------------------------ Target Names SN-2002HH-FIELD, SN-2004ET-FIELD ------------------------------------------------------------------------------------------------------------------------------------