16483( 4) - 25-Jun-2021 10:49:48 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 16483 Version: 4 Check-in Time: 25-Jun-2021 10:49:48 STScI Edit Number: 2 Title A Hunt for Binary Supermassive Black Holes with the VLBA and HST ------------------------------------------------------------------------------------ Type Cycle GO 28 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. Peter Breiding West Virginia University Research Y Corporation CoI: Prof. Michael Eracleous The Pennsylvania State University N CoI: Dr. Jessie Caye Runnoe Vanderbilt University N CoI: Dr. Sarah Burke-Spolaor Associated Universities, Inc. N ------------------------------------------------------------------------------------ Abstract We propose 162.2 hours (including overheads) of Q-band observations with the VLBA in order to explore the underlying nature of eight peculiar active galactic nuclei (AGN). These eight objects originate from a sample of 88 SDSS quasars identified as having broad emission lines that are velocity-offset (>1000~km/s) from the host galaxy (Eracleous et al., 2012), potentially indicating a binary supermassive black hole (SMBH). However, there are two other leading models for such shifts: a recoiling post-merger SMBH, or a broad line region (BLR) gas outflow caused by a jet or accretion disk wind. We have previously followed up all 88 objects from Eracleous et al. (2012) with VLA X-band observations. We then followed up the brightest VLA-detected objects with VLBA X-band observations. Our proposed Q-band observations of the eight brightest objects will provide a critical 5-fold increase in angular resolution over the previous VLBA X-band observations, and test the binary hypothesis down to sub-pc separations in all cases. In addition, we request 9 orbits with the HST in order to determine the SMBH masses, assess the host galaxies for any evidence of recent major galaxy mergers, and measure the photometric centers that will allow more precise determination of radio/optical offsets. ------------------------------------------------------------------------------------ Observations Description ------------------------ The overall scientific goals of this proposal are two-fold: image the faint morphological structures of the quasar host galaxies for any indications of a recent merger (such as tidal tails); and photometricly model the bulge of the host galaxy in order to precisely determine its light center, along with measuring the bulge luminosity for determining a black hole mass. The precise measuement of the bulge's photocenter is necessary for comparison with the VLBI radio core position to determine if there are any offset AGN which may be indicative of a recoiling black hole. Given these requirements, we need a good description of the PSF in the F125W filter, for the optical quasar subtraction and photometric analysis of the host. Hence, we are observing the white dwarf star to get a picture of the PSF with same instrument configuration, and we are using a 4-point (box) dithering pattern to better sample the PSF. Since the expected host galaxies are faint, we chose the WFC3 IR camera in order to readout exposures in a STEP sequence (recommended for high dynamic range imaging), alllowing us to build up sensitivity to low surface brightness 16483( 4) - 25-Jun-2021 10:49:48 - [ 2] features. Our estimated necessary exposure times are all within the time allowed during a single orbit. However, since our stratgey is to observe one target per orbit, we intend to use all of the possible time during the orbit towards the target exposure to maximize our sensitivity. To this end, we adjust the number of readout samples to be within the constraints allowed for a single orbit. ------------------------------------------------------------------------------------ 16483( 4) - 25-Jun-2021 10:49:48 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 SDSSJ095036. GALAXY, QUASAR RA=09H50M36.7565S, J2000 Z = V = 18.34 +/- 0.1 B=18.74 75+512838.1 DEC=+51D28'38.07" 0.2144 Reference Frame: Other: SIMBAD Comments: This object was generated by the targetselector and retrieved from the SIMBAD database. Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 2015.5 -2.333452049979895E-5 0.001368 0.0 ------------------------------------------------------------------------------------------------------------------------------------ 2 SDSSJ102106. GALAXY, QUASAR RA=10H21M6.0464S, J2000 Z = V = 18.38 +/- 0.1 B=18.34 04+452331.8 DEC=+45D23'31.82" 0.3637 Reference Frame: Other: SIMBAD Extended: YES Comments: This object was generated by the targetselector and retrieved from the SIMBAD database. Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 2015.5 2.5536952889654054E-5 2.98E-4 0.0 ------------------------------------------------------------------------------------------------------------------------------------ 3 SDSSJ105203. GALAXY, QUASAR RA=10H52M3.1720S, J2000 Z = V = 18.6 +/- 0.1 B=18.5 17+240505.0 DEC=+24D05'4.98" 0.4002 Reference Frame: Other: SIMBAD Extended: YES Comments: This object was generated by the targetselector and retrieved from the SIMBAD database. Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 2015.5 -3.870266875026689E-6 -1.489999931436614E-4 0.0 ------------------------------------------------------------------------------------------------------------------------------------ 4 SDSSJ151443. GALAXY, QUASAR RA=15H14M43.0683S, J2000 Z = V = 17.01 +/- 0.1 B=16.79 07+365050.4 DEC=+36D50'50.36" 0.3711 Reference Frame: Other: SIMBAD Extended: YES Comments: This object was generated by the targetselector and retrieved from the SIMBAD database. Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 2015.5 -4.998523195449508E-7 4.7E-5 0.0 ------------------------------------------------------------------------------------------------------------------------------------ 5 LAWD-52 CALIBRATION, POINT RA=13H38M49.2464S, J2000 V = 26 V = 12.6 +/- 0.1 SPREAD FUNCTION DEC=+70D17'7.26" Reference Frame: Other: SIMBAD Extended: NO Comments: This object was generated by the targetselector and retrieved from the SIMBAD database. Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 2015.5 -0.07946439774064423 -0.02460799998971197 0.0 ------------------------------------------------------------------------------------------------------------------------------------ 16483( 4) - 25-Jun-2021 10:49:48 - [ 4] Patterns ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 1 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 NO ------------------------------------------------------------------------------------------------------------------------------------ 16483( 4) - 25-Jun-2021 10:49:48 - [ 5] 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| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 SDSSJ095036 WFC3/IR MULTIAC IR F125W NSAMP=10, SAMP-SEQ=STEP200 1 DEF PATTERN 1 1 .75+512838. CUM (2396.925 1 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 | ------------------------------------------------------------------------------------------------------------------------------------ SDSSJ095036.75+5128 1 WFC3/IR MULTIAC IR F125W 1 none none none 1 N/A 38.1 CUM SDSSJ095036.75+5128 1 WFC3/IR MULTIAC IR F125W 2 none none none 1 N/A 38.1 CUM SDSSJ095036.75+5128 1 WFC3/IR MULTIAC IR F125W 3 none none none 1 N/A 38.1 CUM SDSSJ095036.75+5128 1 WFC3/IR MULTIAC IR F125W 4 none none none 1 N/A 38.1 CUM 16483( 4) - 25-Jun-2021 10:49:48 - [ 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 SDSSJ102106 WFC3/IR MULTIAC IR F125W NSAMP=10, SAMP-SEQ=STEP200 1 DEF PATTERN 1 1 .04+452331. CUM (2396.925 8 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 | ------------------------------------------------------------------------------------------------------------------------------------ SDSSJ102106.04+4523 1 WFC3/IR MULTIAC IR F125W 1 none none none 1 N/A 31.8 CUM SDSSJ102106.04+4523 1 WFC3/IR MULTIAC IR F125W 2 none none none 1 N/A 31.8 CUM SDSSJ102106.04+4523 1 WFC3/IR MULTIAC IR F125W 3 none none none 1 N/A 31.8 CUM SDSSJ102106.04+4523 1 WFC3/IR MULTIAC IR F125W 4 none none none 1 N/A 31.8 CUM 16483( 4) - 25-Jun-2021 10:49:48 - [ 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 SDSSJ105203 WFC3/IR MULTIAC IR F125W NSAMP=10, SAMP-SEQ=STEP200 1 DEF PATTERN 1 1 .17+240505. CUM (2396.925 0 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 | ------------------------------------------------------------------------------------------------------------------------------------ SDSSJ105203.17+2405 1 WFC3/IR MULTIAC IR F125W 1 none none none 1 N/A 05.0 CUM SDSSJ105203.17+2405 1 WFC3/IR MULTIAC IR F125W 2 none none none 1 N/A 05.0 CUM SDSSJ105203.17+2405 1 WFC3/IR MULTIAC IR F125W 3 none none none 1 N/A 05.0 CUM SDSSJ105203.17+2405 1 WFC3/IR MULTIAC IR F125W 4 none none none 1 N/A 05.0 CUM 16483( 4) - 25-Jun-2021 10:49:48 - [ 8] 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 SDSSJ151443 WFC3/IR MULTIAC IR F125W NSAMP=10, SAMP-SEQ=STEP200 1 DEF PATTERN 1 1 .07+365050. CUM (2396.925 4 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 | ------------------------------------------------------------------------------------------------------------------------------------ SDSSJ151443.07+3650 1 WFC3/IR MULTIAC IR F125W 1 none none none 1 N/A 50.4 CUM SDSSJ151443.07+3650 1 WFC3/IR MULTIAC IR F125W 2 none none none 1 N/A 50.4 CUM SDSSJ151443.07+3650 1 WFC3/IR MULTIAC IR F125W 3 none none none 1 N/A 50.4 CUM SDSSJ151443.07+3650 1 WFC3/IR MULTIAC IR F125W 4 none none none 1 N/A 50.4 CUM 16483( 4) - 25-Jun-2021 10:49:48 - [ 9] Visit: 05 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 LAWD-52 WFC3/IR MULTIAC IR F125W NSAMP=10, SAMP-SEQ=STEP200 1 DEF PATTERN 1 1 CUM (2396.925 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 | ------------------------------------------------------------------------------------------------------------------------------------ LAWD-52 1 WFC3/IR MULTIAC IR F125W 1 none none none 1 N/A CUM LAWD-52 1 WFC3/IR MULTIAC IR F125W 2 none none none 1 N/A CUM LAWD-52 1 WFC3/IR MULTIAC IR F125W 3 none none none 1 N/A CUM LAWD-52 1 WFC3/IR MULTIAC IR F125W 4 none none none 1 N/A CUM 16483( 4) - 25-Jun-2021 10:49:48 - [ 10] Visit: 52 Visit Requirements: On Hold Comments: Additional Comments: HOPR repeat of visit 02 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 SDSSJ102106 WFC3/IR MULTIAC IR F125W NSAMP=10, SAMP-SEQ=STEP200 1 DEF GS ACQ SCENARIO BASE1BE; .04+452331. CUM (2396.925 PATTERN 1 1 8 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 | ------------------------------------------------------------------------------------------------------------------------------------ SDSSJ102106.04+4523 1 WFC3/IR MULTIAC IR F125W 1 none none none 1 N/A 31.8 CUM SDSSJ102106.04+4523 1 WFC3/IR MULTIAC IR F125W 2 none none none 1 N/A 31.8 CUM SDSSJ102106.04+4523 1 WFC3/IR MULTIAC IR F125W 3 none none none 1 N/A 31.8 CUM SDSSJ102106.04+4523 1 WFC3/IR MULTIAC IR F125W 4 none none none 1 N/A 31.8 CUM 16483( 4) - 25-Jun-2021 10:49:48 - [ 11] Visit: 53 Visit Requirements: On Hold Comments: Additional Comments: HOPR repeat of visit 03 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 SDSSJ105203 WFC3/IR MULTIAC IR F125W NSAMP=10, SAMP-SEQ=STEP200 1 DEF GS ACQ SCENARIO BASE1BE; .17+240505. CUM (2396.925 PATTERN 1 1 0 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 | ------------------------------------------------------------------------------------------------------------------------------------ SDSSJ105203.17+2405 1 WFC3/IR MULTIAC IR F125W 1 none none none 1 N/A 05.0 CUM SDSSJ105203.17+2405 1 WFC3/IR MULTIAC IR F125W 2 none none none 1 N/A 05.0 CUM SDSSJ105203.17+2405 1 WFC3/IR MULTIAC IR F125W 3 none none none 1 N/A 05.0 CUM SDSSJ105203.17+2405 1 WFC3/IR MULTIAC IR F125W 4 none none none 1 N/A 05.0 CUM 16483( 4) - 25-Jun-2021 10:49:48 - [ 12] Summary Form for Proposal 16483 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures IR ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFC3/IR ------------------------------------------------------------------------------------------------------------------------------------ Opmodes MULTIACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters NSAMP=10, SAMP-SEQ=STEP200 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements GS ACQ SCENARIO BASE1BE, PATTERN 1 1 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F125W ------------------------------------------------------------------------------------------------------------------------------------ Target Names LAWD-52, SDSSJ095036.75+512838.1, SDSSJ102106.04+452331.8, SDSSJ105203.17+240505.0, SDSSJ151443.07+365050.4 ------------------------------------------------------------------------------------------------------------------------------------