13843( 4) - 14-Jul-2014 15:09:58 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 13843 Version: 4 Check-in Time: 14-Jul-2014 15:09:58 STScI Edit Number: 1 Title A Candidate Recoiling Black Hole in a Nearby Dwarf Galaxy ------------------------------------------------------------------------------------ Type Cycle GO 22 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. Michael J Koss Eidgenossiche Technische Hochschule (ETH) Y CoI: Dr. Laura Blecha University of Maryland N CoI: Dr. Richard Mushotzky University of Maryland N CoI: Prof. Sylvain Veilleux University of Maryland N CoI: Dr. Daniel Stern Jet Propulsion Laboratory N CoI: Prof. Kevin Schawinski Eidgenossiche Technische Hochschule (ETH) N CoI: Dr. Benny Trakhtenbrot Eidgenossiche Technische Hochschule (ETH) N CoI: Prof. Alex V. Filippenko University of California - Berkeley N ------------------------------------------------------------------------------------ Abstract We have discovered a BH recoil candidate offset by 800 pc from a nearby dwarf galaxy. The object, SDSS1133, shows offset broad lines and strong variability. While originally classified as a supernova because of its non-detection in 2005, we detect it in recent and past observations over 63 years. Using high-resolution adaptive optics observations, we constrain the source emission region to be <12 pc. Overall these properties are consistent with theoretical predictions for a runaway BH ejected from its host by gravitational-wave recoil following a merger. We propose a small, 4 orbit HST observation using the COS spectrograph in the FUV, to test for broad C IV emission and other high ionization emission lines which would decisively favor the recoiling BH interpretation. The unique UV spectroscopic capability of HST is critical to decide whether this is a recoiling black hole or an unprecedented 50 year outbursting LBV star (e.g. Eta Carina) followed by a unique long duration SN IIn with rebrightening. Either discovery would be extremely exciting. Finally, SDSS1133 has recently undergone a 1.3 mag rebrightening in PanSTARRS imaging suggesting that the coming year is a critical time to observe the source at maximum. ------------------------------------------------------------------------------------ Observations Description ------------------------ Our main focus is to study the broad line C IV 1550 emission along with other nearby UV spectral lines (Lyman alpha, N V 1240, and SiIV+OIV complex near 1400) by measuring their width and flux. The medium-resolution COS FUV modes results in a discovery space (throughput times wavelength coverage) best suited for observations of faint FUV point sources, it is therefore the preferred instrument for this study. The astrometry is based on the centroid of the point source from SDSS and PS1 observations in the optical. We expect at most a 0.3'' uncertainty given fits to many images. Lower spatial resolution images in the FUV and NUV with SWIFT 13843( 4) - 14-Jul-2014 15:09:58 - [ 2] show a point source consistent with the optical image. High resolution images in the NIR AO and NIR narrow band (tracing Paschen Beta which also traces NUV emission from SF) suggest a point source at 0.1'' offset by 6'' from the galaxy nucleus. We will use a NUV ACQ/Image exposure first, which we also use for science purposes to confirm it is a point source in the NUV as well as NIR. For exposure time planning we use NUV+FUV observations from SWIFT and FUV from galex as well as the broad hbeta emission for line emission. While the NUV show significant contamination from the galaxy, at HST resolutions similar to the NIR AO, the point source is much brighter than the surrounding background and even the nucleus of the galaxy 6'' away so centroiding is not an issue. For the ACQ/Image, we use a S/N of 40 and a conservative estimate that our NUV emission is overestimated by a mag because of contamination from the galaxy. Obtaining a full spectrum of an object requires several set-ups and exposures (5 setups for G130M in one orbit and 4 setups for G160M in another orbit), but covers a large spectra range 1140-1800 to observe the interested lines. The separate exposures will be coadded using the routines provided on the COS Tools Web site. ------------------------------------------------------------------------------------ 13843( 4) - 14-Jul-2014 15:09:58 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 SDSS1133 UNIDENTIFIED, ACCRETION RA=11H33M23.9738S +/- 0.2", J2000 Z = V = 19.0 +/- 1 DISK, BLR, NUCLEUS DEC=+55D04'15.89" +/- 0.1" 0.007845 Reference Frame: ICRS Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 2000 0.0 0.0 0 ------------------------------------------------------------------------------------------------------------------------------------ 13843( 4) - 14-Jul-2014 15:09:58 - [ 4] 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 SDSS1133 COS/NUV ACQ/IMA PSA MIRRORA 1 422 S (422 GE S) ------------------------------------------------------------------------------------------------------------------------------------ 2 SDSS1133 COS/FUV TIME-TA PSA G160M 1600 BUFFER-TIME=799, FP-POS=ALL 1 909 S G (3686 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 SDSS1133 COS/FUV TIME-TA PSA G160M 1623 BUFFER-TIME=874, FP-POS=ALL 1 984 S SAME POS AS 2 G see below (3961 S) ------------------------------------------------------------------------------------------------------------------------------------ 4 SDSS1133 COS/FUV TIME-TA PSA G130M 1300 BUFFER-TIME=1500, FP-POS=ALL 1 287 S SAME POS AS 2 G (1148 S) ------------------------------------------------------------------------------------------------------------------------------------ 5 SDSS1133 COS/FUV TIME-TA PSA G130M 1318 BUFFER-TIME=1500, FP-POS=ALL 1 288 S SAME POS AS 2 G (1152 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 | ------------------------------------------------------------------------------------------------------------------------------------ SDSS1133 1 COS/NUV ACQ/IMA PSA MIRRORA none none none none 1 N/A GE SDSS1133 2 COS/FUV TIME-TA PSA G160M 1600 none none none 1 1 N/A G SDSS1133 2 COS/FUV TIME-TA PSA G160M 1600 none none none 2 1 N/A G SDSS1133 2 COS/FUV TIME-TA PSA G160M 1600 none none none 3 2 934.0 S G SDSS1133 2 COS/FUV TIME-TA PSA G160M 1600 none none none 4 2 934.0 S G SDSS1133 3 COS/FUV TIME-TA PSA G160M 1623 none none none 1 2 1009.0 S G SDSS1133 3 COS/FUV TIME-TA PSA G160M 1623 none none none 2 3 N/A G SDSS1133 3 COS/FUV TIME-TA PSA G160M 1623 none none none 3 3 N/A G SDSS1133 3 COS/FUV TIME-TA PSA G160M 1623 none none none 4 3 N/A G SDSS1133 4 COS/FUV TIME-TA PSA G130M 1300 none none none 1 4 N/A G 13843( 4) - 14-Jul-2014 15:09:58 - [ 5] 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 | ------------------------------------------------------------------------------------------------------------------------------------ SDSS1133 4 COS/FUV TIME-TA PSA G130M 1300 none none none 2 4 N/A G SDSS1133 4 COS/FUV TIME-TA PSA G130M 1300 none none none 3 4 N/A G SDSS1133 4 COS/FUV TIME-TA PSA G130M 1300 none none none 4 4 N/A G SDSS1133 5 COS/FUV TIME-TA PSA G130M 1318 none none none 1 4 N/A G SDSS1133 5 COS/FUV TIME-TA PSA G130M 1318 none none none 2 4 N/A G SDSS1133 5 COS/FUV TIME-TA PSA G130M 1318 none none none 3 4 N/A G SDSS1133 5 COS/FUV TIME-TA PSA G130M 1318 none none none 4 4 N/A G 13843( 4) - 14-Jul-2014 15:09:58 - [ 6] Summary Form for Proposal 13843 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures PSA ------------------------------------------------------------------------------------------------------------------------------------ Configurations COS/FUV, COS/NUV ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACQ/IMAGE, TIME-TAG ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters BUFFER-TIME=1500, BUFFER-TIME=799, BUFFER-TIME=874, FP-POS=ALL ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements SAME POS AS 2 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements G130M, G160M, MIRRORA ------------------------------------------------------------------------------------------------------------------------------------ Target Names SDSS1133 ------------------------------------------------------------------------------------------------------------------------------------