15162( 4) - 06-Jan-2022 17:51:26 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 15162 Version: 4 Check-in Time: 06-Jan-2022 17:51:26 STScI Edit Number: 1 Title Constraining the Late-Time Light Curve Behavior of Three Diverse Superluminous Supernovae ------------------------------------------------------------------------------------ Type Cycle GO 25 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. Peter Blanchard Northwestern University Y CoI: Dr. Matt Nicholl University of Birmingham N CoI: Prof. Edo Berger Harvard University N CoI: Daichi Hiramatsu Center for Astrophysics | Harvard & N Smithsonian ------------------------------------------------------------------------------------ Abstract The current generation of untargeted optical time-domain surveys have led to the discovery of rare and extreme transients such as superluminous supernovae (SLSNe). The mechanism that powers the hydrogen-poor Type I SLSNe remains elusive, though models such as a magnetar central engine and interaction with a hydrogen-poor circumstellar medium are both major contenders. One of the most promising observational methods available to test these models is to track the light curve evolution to very late times where model predictions diverge. We propose to obtain ACS/WFC imaging of three Type I SLSNe (PS16aqv, PS16fgt, and Gaia16apd) at greater than 500 rest-frame days after peak brightness when only HST provides the required sensitivity. These events span the diversity of decline timescales and colors exhibited by Type I SLSNe and will allow us to compare the late-time evolution of a diverse sample of events among themselves and with model predictions. These HST observation will be the latest ever of Type I SLSNe and will help to address important questions regarding their power source and diversity. ------------------------------------------------------------------------------------ Observations Description ------------------------ In Cycle 25 we will use 6 orbits to observe three superluminous supernovae (PS16aqv, PS16fgt, and Gaia16apd) using ACS/WFC. We will obtain 2 orbits for each object, separated by at least a few months, to measure the late-time lightcurve decline rate. In Cycle 26 we will obtain 3 additional orbits (1 orbit per object) to measure the host galaxy flux after the supernovae have faded below r ~ 30. ------------------------------------------------------------------------------------ 15162( 4) - 06-Jan-2022 17:51:26 - [ 2] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 PS16AQV STAR, SUPERNOVA RA=14H10M44.5500S, J2000 Z = 0.20 V = 26 supernova: i = 26, host: i = DEC=-10D09'35.40" 22.8 Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 2 PS16FGT STAR, SUPERNOVA RA=02H44M25.8200S, J2000 Z = 0.30 V = 24 DEC=+19D10'42.60" Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 3 GAIA16APD STAR, SUPERNOVA RA=12H02M51.7100S, J2000 Z = 0.10 V = 24 supernova: r = 24, host: r = DEC=+44D15'27.40" 21.7 Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 15162( 4) - 06-Jan-2022 17:51:26 - [ 3] Patterns ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 1 Primary_Pattern Secondary_Pattern Pattern_Type ACS-WFC-DITHER-BOX Pattern_Purpose DITHER Number_Of_Points 4 Point_Spacing 0.262 Line_Spacing 0.192 Coordinate_Frame POS-TARG Pattern_Orient 18.39 Angle_Between_Sides 68.14 Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ 15162( 4) - 06-Jan-2022 17:51:26 - [ 4] Visit: 01 Visit Requirements: BEFORE 15-DEC-2017:00:00:00 On Hold Comments: Additional Comments: First visit for Gaia16apd 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 GAIA16APD ACS/WFC ACCUM WFC1 F625W 1 545 S PATTERN 1 1 (2180 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 | ------------------------------------------------------------------------------------------------------------------------------------ GAIA16APD 1 ACS/WFC ACCUM WFC1 F625W 1 none none none 1 N/A GAIA16APD 1 ACS/WFC ACCUM WFC1 F625W 2 none none none 1 N/A GAIA16APD 1 ACS/WFC ACCUM WFC1 F625W 3 none none none 1 N/A GAIA16APD 1 ACS/WFC ACCUM WFC1 F625W 4 none none none 1 N/A 15162( 4) - 06-Jan-2022 17:51:26 - [ 5] Visit: 02 Visit Requirements: ORIENT 285D TO 310 D; ORIENT 10D TO 80 D; ORIENT 100D TO 170 D; ORIENT 190D TO 265 D; BETWEEN 01-JAN-2018:00:00:00 AND 01-MAR-2018:00:00:00 On Hold Comments: Additional Comments: First visit for PS16fgt 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 PS16FGT ACS/WFC ACCUM WFC1 F625W 1 535 S PATTERN 1 1 (2140 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 | ------------------------------------------------------------------------------------------------------------------------------------ PS16FGT 1 ACS/WFC ACCUM WFC1 F625W 1 none none none 1 N/A PS16FGT 1 ACS/WFC ACCUM WFC1 F625W 2 none none none 1 N/A PS16FGT 1 ACS/WFC ACCUM WFC1 F625W 3 none none none 1 N/A PS16FGT 1 ACS/WFC ACCUM WFC1 F625W 4 none none none 1 N/A 15162( 4) - 06-Jan-2022 17:51:26 - [ 6] Visit: 03 Visit Requirements: BEFORE 15-JAN-2018:00:00:00 On Hold Comments: Additional Comments: First visit for PS16aqv 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 PS16AQV ACS/WFC ACCUM WFC1 F775W 1 535 S PATTERN 1 1 (2140 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 | ------------------------------------------------------------------------------------------------------------------------------------ PS16AQV 1 ACS/WFC ACCUM WFC1 F775W 1 none none none 1 N/A PS16AQV 1 ACS/WFC ACCUM WFC1 F775W 2 none none none 1 N/A PS16AQV 1 ACS/WFC ACCUM WFC1 F775W 3 none none none 1 N/A PS16AQV 1 ACS/WFC ACCUM WFC1 F775W 4 none none none 1 N/A 15162( 4) - 06-Jan-2022 17:51:26 - [ 7] Visit: 04 Visit Requirements: AFTER 01 BY 80 D TO 110 D On Hold Comments: Additional Comments: Second visit for Gaia16apd 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 GAIA16APD ACS/WFC ACCUM WFC1 F625W 1 545 S PATTERN 1 1 (2180 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 | ------------------------------------------------------------------------------------------------------------------------------------ GAIA16APD 1 ACS/WFC ACCUM WFC1 F625W 1 none none none 1 N/A GAIA16APD 1 ACS/WFC ACCUM WFC1 F625W 2 none none none 1 N/A GAIA16APD 1 ACS/WFC ACCUM WFC1 F625W 3 none none none 1 N/A GAIA16APD 1 ACS/WFC ACCUM WFC1 F625W 4 none none none 1 N/A 15162( 4) - 06-Jan-2022 17:51:26 - [ 8] Visit: 05 Visit Requirements: ORIENT 285D TO 310 D; ORIENT 10D TO 80 D; ORIENT 100D TO 170 D; ORIENT 190D TO 265 D; AFTER 02 BY 90 D TO 150 D On Hold Comments: Additional Comments: Second visit for PS16fgt 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 PS16FGT ACS/WFC ACCUM WFC1 F625W 1 535 S PATTERN 1 1 (2140 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 | ------------------------------------------------------------------------------------------------------------------------------------ PS16FGT 1 ACS/WFC ACCUM WFC1 F625W 1 none none none 1 N/A PS16FGT 1 ACS/WFC ACCUM WFC1 F625W 2 none none none 1 N/A PS16FGT 1 ACS/WFC ACCUM WFC1 F625W 3 none none none 1 N/A PS16FGT 1 ACS/WFC ACCUM WFC1 F625W 4 none none none 1 N/A 15162( 4) - 06-Jan-2022 17:51:26 - [ 9] Visit: 06 Visit Requirements: AFTER 03 BY 60 D TO 100 D On Hold Comments: Additional Comments: Second visit for PS16aqv 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 PS16AQV ACS/WFC ACCUM WFC1 F775W 1 535 S PATTERN 1 1 (2140 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 | ------------------------------------------------------------------------------------------------------------------------------------ PS16AQV 1 ACS/WFC ACCUM WFC1 F775W 1 none none none 1 N/A PS16AQV 1 ACS/WFC ACCUM WFC1 F775W 2 none none none 1 N/A PS16AQV 1 ACS/WFC ACCUM WFC1 F775W 3 none none none 1 N/A PS16AQV 1 ACS/WFC ACCUM WFC1 F775W 4 none none none 1 N/A 15162( 4) - 06-Jan-2022 17:51:26 - [ 10] Summary Form for Proposal 15162 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures WFC1 ------------------------------------------------------------------------------------------------------------------------------------ Configurations ACS/WFC ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements AFTER 01 BY 80 D TO 110 D, AFTER 02 BY 90 D TO 150 D, AFTER 03 BY 60 D TO 100 D, BEFORE 15-DEC-2017:00:00:00, BEFORE 15-JAN-2018:00:00:00, BETWEEN 01-JAN-2018:00:00:00 AND 01-MAR-2018:00:00:00, ORIENT 100D TO 170 D, ORIENT 10D TO 80 D, ORIENT 190D TO 265 D, ORIENT 285D TO 310 D, PATTERN 1 1 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F625W, F775W ------------------------------------------------------------------------------------------------------------------------------------ Target Names GAIA16APD, PS16AQV, PS16FGT ------------------------------------------------------------------------------------------------------------------------------------