16877( 5) - 28-Jul-2022 12:08:47 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 16877 Version: 5 Check-in Time: 28-Jul-2022 12:08:47 STScI Edit Number: 0 Title Determining the host sub-structure and local environment characteristics of highly-active FRB 20201124A ------------------------------------------------------------------------------------ Type Cycle GO 29 ------------------------------------------------------------------------------------ Investigators Contact? PI: Alexandra Mannings University of California - Santa Cruz Y CoI: Dr. Nicolas Tejos Pontificia Universidad Catolica de N Valparaiso CoI: Dr. Wen-fai Fong Northwestern University N CoI: Dr. Jason X. Prochaska University of California - Santa Cruz N CoI: Dr. Marc Rafelski Space Telescope Science Institute N CoI: Dr. Jason Hessels Stichting Astronomisch Onderzoek in N Nederland (ASTRON) CoI: Kenzie Nimmo Universiteit van Amsterdam N CoI: Dr. Charles Kilpatrick Northwestern University N CoI: Ms. Tarraneh Eftekhari Smithsonian Institution Astrophysical N Observatory CoI: Dr. Adam Travis Deller Swinburne University of Technology N CoI: Dr. Benito Marcote Joint Institute for VLBI in Europe N CoI: Dr. Franz Kirsten Chalmers University of Technology N CoI: Dr. Shivani Bhandari CSIRO, Australia Telescope National N Facility CoI: Dr. Stuart Ryder Macquarie University N CoI: Dr. Ryan Shannon Swinburne University of Technology N CoI: Cherie Day McGill University N CoI: Dr. Clancy W. James International Centre for Radio Astronomy N Research, ICRAR ------------------------------------------------------------------------------------ Abstract We propose HST mid-cycle imaging of the host galaxy of a fast radio burst (FRB) localized to milliarcsecond precision to constrain the origin of this enigmatic, highly active, repeating burst. Recent publications (based on HST observations) have established that FRBs occur primarily in star-forming galaxies with galactocentric offsets ranging from ~1 to 10 kpc. These data also indicate a high incidence of spiral arm structure in the near-IR band and suggest the frequent appearance of FRBs within these arms. With deep WFC3/UVIS 475X images we will observe the host of FRB 20201124A to precisely measure its spiral arm structure and to add to the quantitative assessment of the distribution of FRB progenitor locations relative to the arms. Following similar studies on other transients (e.g. supernovae), our experiment will yield new constraints on FRB progenitor channels by establishing the relationship of FRBs to recent star-formation and their progenitor lifetimes, using the high-resolution HST imaging in conjunction with VLA imaging of radio emission (presumed associated to recent star formation). The proposed observations with deep HST/WFC3 F160W will also determine the morphology, galactocentric offset, radial light distribution and local measure of the stellar mass surface density. The observations will utilize HST's high angular resolution imaging and UV sensitivity to measure the immediate galactic environment of this FRB and the nature of star 16877( 5) - 28-Jul-2022 12:08:47 - [ 2] formation to within a single pixel (0.1 kpc) of the burst's origin. We commit to rapid publication and release of the data to guide future research of this unique source. ------------------------------------------------------------------------------------ Observations Description ------------------------ We will observe this host over 2 orbits; 1 orbit in F475X and 1 orbit in F160W. As this is a dusty, star-forming galaxy with a high extinction of E(B-V)=0.7315, we choose to observe using a broad NUV filter in order to achieve higher throughput. This will allow us to effectively image regions with current or recent star formation (and therefore younger stellar populations), make morphological measurements, achieve high contrast between arm and inter-arm regions, and sample the rest-frame NUV enabling a measurement of the SFR. The NIR will be sampled by the F160W filter in order to differentiate between the foreground and background host and study low surface brightness features that trace the older stellar population. In order to obtain images clean of cosmic rays and image artifacts and sub-sample the PSF for better pixel sampling, we will obtain 4 exposures in F475X in 1 orbit. We will use a custom 4 point dither pattern, 5 times larger than the default box pattern to dither over fixed pattern noise. These observations require no use of post-flash. To maximize UV throughput and minimize our pixel-based CTE correction, we place the target on chip 2 close to the readout. For the NIR observations, we wish to stay in the linear regime and minimize persistence with this bright target, and therefore will use SPAR25 with NSAMP of 15. Since this sets the exposure time per dither position, we end up with 7 dither positions of 353s in one orbit. We take dither positions from WFC3 ISR 2016-14 (pg 17) to get a good dither for the pixel phase and artificat mitigation. We multiply those values by 3 to better deal with IR blobs, and self persistence. We request that the NUV and NIR observations are obtained at the same ORIENT to aid in alignment of the NUV and NIR images, and will offset the images to obtain maximum overlap of the two filters. We request an orient from the NIR imaging, from -10 to +10. ------------------------------------------------------------------------------------ 16877( 5) - 28-Jul-2022 12:08:47 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 FRB20201124 GALAXY, DISK RA=05H08M3.4770S +/- 0.012", J2000 Z = V = 19.5 +/- 0.029 DEC=+26D03'37.93" +/- 0.012" 0.0981 Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 16877( 5) - 28-Jul-2022 12:08:47 - [ 4] Patterns ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 2 Primary_Pattern Secondary_Pattern Pattern_Type WFC3-UVIS-DITHER-BOX Pattern_Purpose DITHER Number_Of_Points 4 Point_Spacing 0.865 Line_Spacing 0.56 Coordinate_Frame POS-TARG Pattern_Orient 23.884 Angle_Between_Sides 81.785 Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ 16877( 5) - 28-Jul-2022 12:08:47 - [ 5] Visit: 01 (201124_IR) 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 FRB20201124 WFC3/IR MULTIAC IR F160W NSAMP=15, SAMP-SEQ=SPARS25 1 DEF CUM (352.94 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 FRB20201124 WFC3/IR MULTIAC IR F160W NSAMP=15, SAMP-SEQ=SPARS25 1 DEF POS TARG 2.1, 0.189 CUM (352.94 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 FRB20201124 WFC3/IR MULTIAC IR F160W NSAMP=15, SAMP-SEQ=SPARS25 1 DEF POS TARG 4.197, 0.075 CUM (352.94 S) ------------------------------------------------------------------------------------------------------------------------------------ 4 FRB20201124 WFC3/IR MULTIAC IR F160W NSAMP=15, SAMP-SEQ=SPARS25 1 DEF POS TARG 0.204, 2.118 CUM (352.94 S) ------------------------------------------------------------------------------------------------------------------------------------ 5 FRB20201124 WFC3/IR MULTIAC IR F160W NSAMP=15, SAMP-SEQ=SPARS25 1 DEF POS TARG 2.304, 1.944 CUM (352.94 S) ------------------------------------------------------------------------------------------------------------------------------------ 6 FRB20201124 WFC3/IR MULTIAC IR F160W NSAMP=15, SAMP-SEQ=SPARS25 1 DEF POS TARG 4.404, 2.07 CUM (352.94 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 | ------------------------------------------------------------------------------------------------------------------------------------ FRB20201124 1 WFC3/IR MULTIAC IR F160W none none none none 1 N/A CUM FRB20201124 2 WFC3/IR MULTIAC IR F160W none none none none 1 N/A CUM FRB20201124 3 WFC3/IR MULTIAC IR F160W none none none none 1 N/A CUM FRB20201124 4 WFC3/IR MULTIAC IR F160W none none none none 1 N/A CUM FRB20201124 5 WFC3/IR MULTIAC IR F160W none none none none 1 N/A CUM FRB20201124 6 WFC3/IR MULTIAC IR F160W none none none none 1 N/A CUM 16877( 5) - 28-Jul-2022 12:08:47 - [ 6] Visit: 02 (201124_UV) Visit Requirements: ORIENT -10D TO 10D FROM 01 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 FRB20201124 WFC3/UVI ACCUM UVIS2-C1K F475X 1 597 S PATTERN 2 1 S 1C-CTE (2388 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 | ------------------------------------------------------------------------------------------------------------------------------------ FRB20201124 1 WFC3/UVI ACCUM UVIS2-C1 F475X 1 none none none 1 N/A S K1C-CTE FRB20201124 1 WFC3/UVI ACCUM UVIS2-C1 F475X 2 none none none 1 N/A S K1C-CTE FRB20201124 1 WFC3/UVI ACCUM UVIS2-C1 F475X 3 none none none 1 N/A S K1C-CTE FRB20201124 1 WFC3/UVI ACCUM UVIS2-C1 F475X 4 none none none 1 N/A S K1C-CTE 16877( 5) - 28-Jul-2022 12:08:47 - [ 7] Summary Form for Proposal 16877 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures IR, UVIS2-C1K1C-CTE ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFC3/IR, WFC3/UVIS ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM, MULTIACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters NSAMP=15, SAMP-SEQ=SPARS25 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ORIENT -10D TO 10D FROM 01, PATTERN 2 1, POS TARG 0.204, 2.118, POS TARG 2.1, 0.189, POS TARG 2.304, 1.944, POS TARG 4.197, 0.075, POS TARG 4.404, 2.07 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F160W, F475X ------------------------------------------------------------------------------------------------------------------------------------ Target Names FRB20201124 ------------------------------------------------------------------------------------------------------------------------------------