12785( 2) - 14-Dec-2011 13:46:48 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 12785 Version: 2 Check-in Time: 14-Dec-2011 13:46:48 STScI Edit Number: 0 Title The Strange Supernova or Supernova Impostor SN2011ht ------------------------------------------------------------------------------------ Type Cycle GO/DD 19 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. Roberta M. Humphreys University of Minnesota - Twin Cities CoI: Dr. Kris Davidson University of Minnesota - Twin Cities N CoI: Dr. Jose Luis Prieto Princeton University N CoI: Dr. Peter Roming The Pennsylvania State University N CoI: Dr. Krzysztof Z. Stanek The Ohio State University N CoI: Dr. C. S. Kochanek The Ohio State University N ------------------------------------------------------------------------------------ Abstract SN2011ht may be a peculiar supernova or new type of supernova impostor. In either case, the dramatic increase in its UV flux, combined with its exotic visual spectrum and strong blue continuum, are remarkable and not easy to explain. This object has a supernova-like luminosity with a spectrum that resembles a hot, dense wind, but its steep continuum slope and UV flux are not characteristic of a dense wind, even a very hot one. If the wind is opaque, how can it produce such a steep continuum, and if it isn't, what produces the continuum with the SN-like brightness? To solve the paradox of SN2011ht's spectrum and peculiar eruption, we must look where it is emitting most of its energy, the ultraviolet. Emission and absorption lines in the near-UV will provide badly needed diagnostics on its temperature and other parameters. We are requesting one orbit of Director's Discretionary time to obtain a UV spectrum of SN2011ht. ------------------------------------------------------------------------------------ Observations Description ------------------------ TBD Real Time Justification ----------------------- Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ 12785( 2) - 14-Dec-2011 13:46:48 - [ 2] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 SN2011HT EXT-STAR, SUPERNOVA RA=10H08M10.5900S +/- 0.1", J2000 V = 14.8 +/- 0.5 Flambda=roughly 1e-14 TYPE II DEC=+51D50'57.20" +/- 0.2" in range 2000--3000 AA, based on Swift data. Decreasing about 0.05 magn/day. Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 12785( 2) - 14-Dec-2011 13:46:48 - [ 3] Patterns ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 1 Primary_Pattern Secondary_Pattern Pattern_Type STIS-ALONG-SLIT Pattern_Purpose DITHER Number_Of_Points 2 Point_Spacing 0.43 Line_Spacing Coordinate_Frame POS-TARG Pattern_Orient 90.0 Angle_Between_Sides Center_Pattern NO Pattern_Comments: Mainly to reduce bad pixels, but half-integer rather than integer pixel spacing seems best on general principles. Main reason for dithering in this program: Since G230LB gives poor spectral resolution and S/N will not be high, even one bad pixel amounts to a major defect. ------------------------------------------------------------------------------------------------------------------------------------ 12785( 2) - 14-Dec-2011 13:46:48 - [ 4] 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| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 SN2011HT STIS/CCD ACQ F28X50LP MIRROR 1 2 S ------------------------------------------------------------------------------------------------------------------------------------ 2 SN2011HT STIS/CCD ACCUM 52X0.5E1 G230LB 2375 CR-SPLIT=2 1 540 S PATTERN 1 2 ------------------------------------------------------------------------------------------------------------------------------------ 3 SN2011HT STIS/CCD ACCUM 52X0.5E1 G230MB 2794 CR-SPLIT=2 1 400 S PATTERN 1 3 ------------------------------------------------------------------------------------------------------------------------------------ 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 | ------------------------------------------------------------------------------------------------------------------------------------ SN2011HT 1 STIS/CCD ACQ F28X50LP MIRROR none none none none 1 N/A SN2011HT 2 STIS/CCD ACCUM 52X0.5E1 G230LB 2375 1 none none 1 1 N/A SN2011HT 2 STIS/CCD ACCUM 52X0.5E1 G230LB 2375 1 none none 2 1 N/A SN2011HT 2 STIS/CCD ACCUM 52X0.5E1 G230LB 2375 2 none none 1 1 N/A SN2011HT 2 STIS/CCD ACCUM 52X0.5E1 G230LB 2375 2 none none 2 1 N/A SN2011HT 3 STIS/CCD ACCUM 52X0.5E1 G230MB 2794 1 none none 1 1 N/A SN2011HT 3 STIS/CCD ACCUM 52X0.5E1 G230MB 2794 1 none none 2 1 N/A SN2011HT 3 STIS/CCD ACCUM 52X0.5E1 G230MB 2794 2 none none 1 1 N/A SN2011HT 3 STIS/CCD ACCUM 52X0.5E1 G230MB 2794 2 none none 2 1 N/A 12785( 2) - 14-Dec-2011 13:46:48 - [ 5] 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| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 SN2011HT STIS/CCD ACQ F28X50LP MIRROR 1 2 S ------------------------------------------------------------------------------------------------------------------------------------ 2 SN2011HT STIS/NUV ACCUM 52X0.5 G230L 2376 2 200 S -MAMA ------------------------------------------------------------------------------------------------------------------------------------ 3 SN2011HT STIS/NUV ACCUM 52X0.5 G230M 2800 1 400 S -MAMA ------------------------------------------------------------------------------------------------------------------------------------ 4 SN2011HT STIS/FUV ACCUM 52X0.5 G140L 1425 2 300 S -MAMA ------------------------------------------------------------------------------------------------------------------------------------ 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 | ------------------------------------------------------------------------------------------------------------------------------------ SN2011HT 1 STIS/CCD ACQ F28X50LP MIRROR none none none none 1 N/A SN2011HT 2 STIS/NUV ACCUM 52X0.5 G230L 2376 none none 1 none 1 N/A -MAMA SN2011HT 2 STIS/NUV ACCUM 52X0.5 G230L 2376 none none 2 none 1 N/A -MAMA SN2011HT 3 STIS/NUV ACCUM 52X0.5 G230M 2800 none none none none 1 N/A -MAMA SN2011HT 4 STIS/FUV ACCUM 52X0.5 G140L 1425 none none 1 none 1 N/A -MAMA SN2011HT 4 STIS/FUV ACCUM 52X0.5 G140L 1425 none none 2 none 1 N/A -MAMA 12785( 2) - 14-Dec-2011 13:46:48 - [ 6] Summary Form for Proposal 12785 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures 52X0.5, 52X0.5E1, F28X50LP ------------------------------------------------------------------------------------------------------------------------------------ Configurations STIS/CCD, STIS/FUV-MAMA, STIS/NUV-MAMA ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM, ACQ ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters CR-SPLIT=2 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements PATTERN 1 2, PATTERN 1 3 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements G140L, G230L, G230LB, G230M, G230MB, MIRROR ------------------------------------------------------------------------------------------------------------------------------------ Target Names SN2011HT ------------------------------------------------------------------------------------------------------------------------------------