13851( 2) - 09-Jul-2014 12:40:09 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 13851 Version: 2 Check-in Time: 09-Jul-2014 12:40:09 STScI Edit Number: 0 Title The Origin of Intermediate-Luminosity Red Transients ------------------------------------------------------------------------------------ Type Cycle GO 22 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. Howard E. Bond The Pennsylvania State University Y ------------------------------------------------------------------------------------ Abstract Intermediate-luminosity red transients (ILRTs) are a new class of optical transients. They have maximum luminosities between novae and SNe, and outbursts lasting several months, becoming cool, dusty, and extremely red as the eruptions proceed. A prototype is V838 Mon, which illuminated a spectacular light echo. Their outbursts may be due to catastrophic stellar collisions and mergers. This is demonstrably true for V1309 Sco, which was a contact binary before its eruption and is now a single star. However, it is not yet clear whether all ILRTs are due to mergers. I propose WFC3 imaging of 3 ILRTs: (1) V4332 Sgr, which erupted in the Galactic bulge in 1994, is now a 19th-mag, very red remnant. Based on a high degree of linear polarization in ground-based measurements, it has been proposed that it is surrounded and obscured by a dusty, edge-on envelope, ejected during a stellar merger. If so, V4332 Sgr ought to display a dark lane at HST imaging resolution. (2) M31 RV is an ILRT that occurred in the bulge of M31 in 1988. HST images of the site taken between 1999 and 2010 failed to reveal a credible remnant of this event. However, models of expanding dusty envelopes predict that eventually, as the optical depth diminishes, the remnant should brighten. The passage of 5 years since the last HST observation of the field justifies another attempt to identify the putative merged binary. (3) CK Vul, the bright "nova" of 1670, is a candidate ILRT because of its red color and an outburst light curve resembling that of V838 Mon. A faint bipolar nebula lies at the site of CK Vul, but no credible remnant star has been found in ground-based images. HST resolution may reveal it. ------------------------------------------------------------------------------------ Observations Description ------------------------ I will use WFC3 UVIS and IR channels to image the sites of three intermediate-luminosity transients: V4332 Sgr: exposures in B (F438W), V (F606W), and I (F814W) in order to search for a resolved compact nebula and a possible dark band across it. M31 RV: repeat imaging last done in 2009-2010 in F814W and F160W, to search for any faint red sources that may have brightened since the observations ~5 years ago. CK Vul: deep images in F300X (to search for possible faint, hot star responsible for exciting the faint emission nebula at the outburst site), and in F606W and 13851( 2) - 09-Jul-2014 12:40:09 - [ 2] F160W (to search for a possible faint red remnant star). Standard dithering patterns will be used for all of the imaging. ------------------------------------------------------------------------------------ 13851( 2) - 09-Jul-2014 12:40:09 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 V4332-SGR STAR, CIRCUMSTELLAR RA=18H50M36.7000S, J2000 V = 19 MATTER, DUST LANE, DEC=-21D23'28.90" EJECTA, M III-I Reference Frame: Other: SIMBAD Comments: This object was generated by the targetselector and retrieved from the SIMBAD database. ------------------------------------------------------------------------------------------------------------------------------------ 2 M31-RV EXT-STAR, CIRCUMSTELLAR RA=00H43M2.4330S, J2000 V = 21 MATTER, EJECTA, M III-I DEC=+41D12'56.17" Reference Frame: Other: SIMBAD Comments: This object was generated by the targetselector and retrieved from the SIMBAD database. ------------------------------------------------------------------------------------------------------------------------------------ 3 CK-VUL STAR, CIRCUMSTELLAR RA=19H47M37.9000S, J2000 V = 21 MATTER, CLASSICAL NOVA, DEC=+27D18'42.20" EJECTA, EMISSION LINE NEBULA, INTERACTING BINARY Reference Frame: Other: SIMBAD Comments: This object was generated by the targetselector and retrieved from the SIMBAD database. ------------------------------------------------------------------------------------------------------------------------------------ 13851( 2) - 09-Jul-2014 12:40:09 - [ 4] Patterns ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 1 Primary_Pattern Secondary_Pattern Pattern_Type WFC3-UVIS-DITHER-LINE-3PT Pattern_Purpose DITHER Number_Of_Points 3 Point_Spacing 0.135 Line_Spacing Coordinate_Frame POS-TARG Pattern_Orient 46.84 Angle_Between_Sides Center_Pattern YES ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 2 Primary_Pattern Secondary_Pattern Pattern_Type WFC3-IR-DITHER-LINE-3PT Pattern_Purpose DITHER Number_Of_Points 3 Point_Spacing 0.605 Line_Spacing Coordinate_Frame POS-TARG Pattern_Orient 41.788 Angle_Between_Sides Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 3 Primary_Pattern Secondary_Pattern Pattern_Type WFC3-IR-DITHER-BOX-MIN Pattern_Purpose DITHER Number_Of_Points 4 Point_Spacing 0.572 Line_Spacing 0.365 Coordinate_Frame POS-TARG Pattern_Orient 18.528 Angle_Between_Sides 74.653 Center_Pattern YES ------------------------------------------------------------------------------------------------------------------------------------ 13851( 2) - 09-Jul-2014 12:40:09 - [ 5] Visit: 01 Visit Requirements: ORIENT 177.6D TO 254 D; ORIENT 267.6D TO 294.8 D; ORIENT 316.8D TO 344 D; ORIENT 357.6D TO 74 D; ORIENT 87.6D TO 114.8 D; ORIENT 136.8D TO 164 D On Hold Comments: Additional Comments: UVIS imaging of V4332 Sgr. ORIENT requirements are added to avoid charge bleed and diffraction spikes from a bright neighboring star 10".5 away from target. 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 V4332-SGR WFC3/UVI ACCUM UVIS2-C1K F438W CR-SPLIT=NO, FLASH=12 1 600 S PATTERN 1 1-3 S 1C-SUB see below (1746 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 V4332-SGR WFC3/UVI ACCUM UVIS2-C1K F606W CR-SPLIT=NO, FLASH=12 1 24 S (72 S 1C-SUB S) ------------------------------------------------------------------------------------------------------------------------------------ 3 V4332-SGR WFC3/UVI ACCUM UVIS2-C1K F814W CR-SPLIT=NO, FLASH=12, BLADE=A 1 5 S (15 S) S 1C-SUB ------------------------------------------------------------------------------------------------------------------------------------ 4 V4332-SGR WFC3/UVI ACCUM UVIS2-C1K F814W CR-SPLIT=NO, FLASH=12, BLADE=A 1 5 S (5 S) S 1C-SUB ------------------------------------------------------------------------------------------------------------------------------------ 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 | ------------------------------------------------------------------------------------------------------------------------------------ V4332-SGR 1 WFC3/UVI ACCUM UVIS2-C1 F438W 1 none none none 1 582.0 S S K1C-SUB V4332-SGR 1 WFC3/UVI ACCUM UVIS2-C1 F438W 2 none none none 1 582.0 S S K1C-SUB V4332-SGR 1 WFC3/UVI ACCUM UVIS2-C1 F438W 3 none none none 1 582.0 S S K1C-SUB V4332-SGR 2 WFC3/UVI ACCUM UVIS2-C1 F606W 1 none none none 1 N/A S K1C-SUB V4332-SGR 2 WFC3/UVI ACCUM UVIS2-C1 F606W 2 none none none 1 N/A S K1C-SUB V4332-SGR 2 WFC3/UVI ACCUM UVIS2-C1 F606W 3 none none none 1 N/A S K1C-SUB V4332-SGR 3 WFC3/UVI ACCUM UVIS2-C1 F814W 1 none none none 1 N/A S K1C-SUB V4332-SGR 3 WFC3/UVI ACCUM UVIS2-C1 F814W 2 none none none 1 N/A S K1C-SUB V4332-SGR 3 WFC3/UVI ACCUM UVIS2-C1 F814W 3 none none none 1 N/A S K1C-SUB V4332-SGR 4 WFC3/UVI ACCUM UVIS2-C1 F814W none none none none 1 N/A S K1C-SUB 13851( 2) - 09-Jul-2014 12:40:09 - [ 6] Visit: 02 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| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 M31-RV WFC3/UVI ACCUM UVIS2-C51 F814W CR-SPLIT=NO 1 600 S PATTERN 1 1 S 2C-SUB see below (1776 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 M31-RV WFC3/IR MULTIAC IRSUB256 F160W NSAMP=14, SAMP-SEQ=SPARS25 1 DEF PATTERN 2 2 CUM (872.329 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 | ------------------------------------------------------------------------------------------------------------------------------------ M31-RV 1 WFC3/UVI ACCUM UVIS2-C5 F814W 1 none none none 1 592.0 S S 12C-SUB M31-RV 1 WFC3/UVI ACCUM UVIS2-C5 F814W 2 none none none 1 592.0 S S 12C-SUB M31-RV 1 WFC3/UVI ACCUM UVIS2-C5 F814W 3 none none none 1 592.0 S S 12C-SUB M31-RV 2 WFC3/IR MULTIAC IRSUB256 F160W 1 none none none 1 N/A CUM M31-RV 2 WFC3/IR MULTIAC IRSUB256 F160W 2 none none none 1 N/A CUM M31-RV 2 WFC3/IR MULTIAC IRSUB256 F160W 3 none none none 1 N/A CUM 13851( 2) - 09-Jul-2014 12:40:09 - [ 7] 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| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 CK-VUL WFC3/UVI ACCUM UVIS2-2K2 F656N CR-SPLIT=NO, FLASH=12 1 840 S PATTERN 1 1 S C-SUB (2520 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 CK-VUL WFC3/UVI ACCUM UVIS2-C1K F300X CR-SPLIT=NO, FLASH=12 1 400 S PATTERN 1 2-3 S 1C-SUB see below (1479 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 CK-VUL WFC3/UVI ACCUM UVIS2-C1K F606W CR-SPLIT=NO, FLASH=12 1 100 S (300 S 1C-SUB S) ------------------------------------------------------------------------------------------------------------------------------------ 4 CK-VUL WFC3/IR MULTIAC IRSUB256 F160W NSAMP=5, SAMP-SEQ=SPARS10 2 DEF PATTERN 3 4 CUM (237.31 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 | ------------------------------------------------------------------------------------------------------------------------------------ CK-VUL 1 WFC3/UVI ACCUM UVIS2-2K F656N 1 none none none 1 N/A S 2C-SUB CK-VUL 1 WFC3/UVI ACCUM UVIS2-2K F656N 2 none none none 1 N/A S 2C-SUB CK-VUL 1 WFC3/UVI ACCUM UVIS2-2K F656N 3 none none none 1 N/A S 2C-SUB CK-VUL 2 WFC3/UVI ACCUM UVIS2-C1 F300X 1 none none none 2 493.0 S S K1C-SUB CK-VUL 2 WFC3/UVI ACCUM UVIS2-C1 F300X 2 none none none 2 493.0 S S K1C-SUB CK-VUL 2 WFC3/UVI ACCUM UVIS2-C1 F300X 3 none none none 2 493.0 S S K1C-SUB CK-VUL 3 WFC3/UVI ACCUM UVIS2-C1 F606W 1 none none none 2 N/A S K1C-SUB CK-VUL 3 WFC3/UVI ACCUM UVIS2-C1 F606W 2 none none none 2 N/A S K1C-SUB CK-VUL 3 WFC3/UVI ACCUM UVIS2-C1 F606W 3 none none none 2 N/A S K1C-SUB CK-VUL 4 WFC3/IR MULTIAC IRSUB256 F160W 1 none 1 none 2 N/A CUM CK-VUL 4 WFC3/IR MULTIAC IRSUB256 F160W 1 none 2 none 2 N/A CUM 13851( 2) - 09-Jul-2014 12:40:09 - [ 8] 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 | ------------------------------------------------------------------------------------------------------------------------------------ CK-VUL 4 WFC3/IR MULTIAC IRSUB256 F160W 2 none 1 none 2 N/A CUM CK-VUL 4 WFC3/IR MULTIAC IRSUB256 F160W 2 none 2 none 2 N/A CUM CK-VUL 4 WFC3/IR MULTIAC IRSUB256 F160W 3 none 1 none 2 N/A CUM CK-VUL 4 WFC3/IR MULTIAC IRSUB256 F160W 3 none 2 none 2 N/A CUM CK-VUL 4 WFC3/IR MULTIAC IRSUB256 F160W 4 none 1 none 2 N/A CUM CK-VUL 4 WFC3/IR MULTIAC IRSUB256 F160W 4 none 2 none 2 N/A CUM 13851( 2) - 09-Jul-2014 12:40:09 - [ 9] Summary Form for Proposal 13851 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures IRSUB256, UVIS2-2K2C-SUB, UVIS2-C1K1C-SUB, UVIS2-C512C-SUB ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFC3/IR, WFC3/UVIS ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM, MULTIACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters BLADE=A, CR-SPLIT=NO, FLASH=12, NSAMP=14, NSAMP=5, SAMP-SEQ=SPARS10, SAMP-SEQ=SPARS25 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ORIENT 136.8D TO 164 D, ORIENT 177.6D TO 254 D, ORIENT 267.6D TO 294.8 D, ORIENT 316.8D TO 344 D, ORIENT 357.6D TO 74 D, ORIENT 87.6D TO 114.8 D, PATTERN 1 1, PATTERN 1 1-3, PATTERN 1 2-3, PATTERN 2 2, PATTERN 3 4 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F160W, F300X, F438W, F606W, F656N, F814W ------------------------------------------------------------------------------------------------------------------------------------ Target Names CK-VUL, M31-RV, V4332-SGR ------------------------------------------------------------------------------------------------------------------------------------