13867( 4) - 12-Sep-2014 19:15:54 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 13867 Version: 4 Check-in Time: 12-Sep-2014 19:15:54 STScI Edit Number: 0 Title Testing a Globular Cluster Origin for Elusive Calcium-rich Gap Transients ------------------------------------------------------------------------------------ Type Cycle GO 22 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. Mansi Kasliwal California Institute of Technology Y CoI: Dr. Fang Yuan Australian National University N CoI: Dr. Andrew S. Fruchter Space Telescope Science Institute N CoI: Prof. Shrinivas R. Kulkarni California Institute of Technology N CoI: Dr. Avishay Gal-Yam Weizmann Institute of Science N CoI: Dr. Mark Sullivan University of Southampton N CoI: Dr. Eran O. Ofek Weizmann Institute of Science N CoI: Dr. Daniel Perley California Institute of Technology N CoI: Dr. Peter E. Nugent Lawrence Berkeley National Laboratory N CoI: Dr. John S. Mulchaey Carnegie Institution of Washington N CoI: Mr. Yi Cao California Institute of Technology N CoI: Dr. Robert M. Quimby San Diego State University N CoI: Dr. Stephen Bradley Cenko NASA Goddard Space Flight Center N ------------------------------------------------------------------------------------ Abstract The advent of wide-field synoptic surveys has re-invigorated time domain astronomy. The six magnitude luminosity gap between novae and supernovae is now bridged with multiple classes of explosions that are rarer, fainter and faster than supernovae. Here, we discuss an emerging class of transients with the unique property of a small amount of ejecta dominated by Calcium. The members of this class are located in the middle of nowhere in intra-group/intra-cluster environments, offset by tens of kiloparsec from their putative host galaxy. No single model can yet explain all the observables of "Calcium-rich Gap" transients. The location distribution is inconsistent with stellar mass and yet, strikingly consistent with globular clusters. It has been speculated that the high stellar density in globulars leads to peculiar transients. Thus, we propose to use 4 HST orbits to test a globular cluster origin for these elusive Calcium-rich transients. ------------------------------------------------------------------------------------ Observations Description ------------------------ We would like to obtain deep imaging in one filter for two point source targets: SN2005E and PTF11kmb. We will be using the WFC3/UVIS/F606W setup. We selected the four point dither pattern so that the co-added exposure will be free of radiation hits and would have adequate sub-pixel sampling. Running the ETC, we need a depth of V=29 which requires 5531s at an optiumum SNR=5. Using a four-point dither pattern, and including overheads, this requires a total of two orbits for each target as the visibility per orbit is 54 min. 13867( 4) - 12-Sep-2014 19:15:54 - [ 2] We have no scheduling constraints as we are looking for the quiescent counterpart to these Calcium-rich transients. ------------------------------------------------------------------------------------ 13867( 4) - 12-Sep-2014 19:15:54 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 SN2005E EXT-STAR, SUPERNOVA RA=02H39M14.3400S, J2000 V = 26 DEC=+01D05'55.00" Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 2 PTF11KMB EXT-STAR, SUPERNOVA RA=22H22M53.6100S, J2000 V = 26 DEC=+36D17'36.50" Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 13867( 4) - 12-Sep-2014 19:15:54 - [ 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 NO ------------------------------------------------------------------------------------------------------------------------------------ 13867( 4) - 12-Sep-2014 19:15:54 - [ 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| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 SN2005E WFC3/UVI ACCUM UVIS2 F606W 1 800 S POS TARG -41, -35; S see below PATTERN 1 1 (2625 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 SN2005E WFC3/UVI ACCUM UVIS2 F606W 1 800 S POS TARG -41.34, -35.34; S see below PATTERN 1 2 (2736 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 | ------------------------------------------------------------------------------------------------------------------------------------ SN2005E 1 WFC3/UVI ACCUM UVIS2 F606W 1 none none none 1 875.0 S S SN2005E 1 WFC3/UVI ACCUM UVIS2 F606W 2 none none none 1 875.0 S S SN2005E 1 WFC3/UVI ACCUM UVIS2 F606W 3 none none none 1 875.0 S S SN2005E 2 WFC3/UVI ACCUM UVIS2 F606W 1 none none none 2 912.0 S S SN2005E 2 WFC3/UVI ACCUM UVIS2 F606W 2 none none none 2 912.0 S S SN2005E 2 WFC3/UVI ACCUM UVIS2 F606W 3 none none none 2 912.0 S S 13867( 4) - 12-Sep-2014 19:15:54 - [ 6] Visit: 04 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 PTF11KMB WFC3/UVI ACCUM UVIS2 F606W 1 800 S POS TARG -41.34, -35.34; S see below PATTERN 1 1 (2679 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 PTF11KMB WFC3/UVI ACCUM UVIS2 F606W 1 800 S POS TARG -41, -35; S see below PATTERN 1 2 (2790 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 | ------------------------------------------------------------------------------------------------------------------------------------ PTF11KMB 1 WFC3/UVI ACCUM UVIS2 F606W 1 none none none 1 893.0 S S PTF11KMB 1 WFC3/UVI ACCUM UVIS2 F606W 2 none none none 1 893.0 S S PTF11KMB 1 WFC3/UVI ACCUM UVIS2 F606W 3 none none none 1 893.0 S S PTF11KMB 2 WFC3/UVI ACCUM UVIS2 F606W 1 none none none 2 930.0 S S PTF11KMB 2 WFC3/UVI ACCUM UVIS2 F606W 2 none none none 2 930.0 S S PTF11KMB 2 WFC3/UVI ACCUM UVIS2 F606W 3 none none none 2 930.0 S S 13867( 4) - 12-Sep-2014 19:15:54 - [ 7] Summary Form for Proposal 13867 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures UVIS2 ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFC3/UVIS ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements PATTERN 1 1, PATTERN 1 2, POS TARG -41, -35, POS TARG -41.34, -35.34 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F606W ------------------------------------------------------------------------------------------------------------------------------------ Target Names PTF11KMB, SN2005E ------------------------------------------------------------------------------------------------------------------------------------