0 ----- Attempting Submission 1 (Wed Dec 14 21:47:47 GMT 2016) ----- The Ongoing Search for Supermassive Black Hole Binaries Although we have entered the gravitational wave era of astronomy, to date there is no definitive electromagnetic evidence for sub-parsec supermassive binary black holes at cosmological distances. We propose to obtain three-band radio spectra of six promising SMBHB candidates. These six were selected from 80,000 quasars in the Sloan Digital Sky Survey to have anomalous spectral energy distributions best explained by a gap cleared in the accretion disk by the orbiting secondary black hole. Multi-frequency radio observations are required to remove contamination from synchrotron sources that peak in the far-to-mid-IR. We also request 6 orbits with HST to acquire simultaneous UV-NIR SEDs; only HST has the UV sensitivity require to remove potential ambiguity due to variability. Determining the fraction of binary black holes will help predict the level of the gravitational wave background that may soon be detected by Pulsar Timing Arrays. Although we have entered the gravitational wave era of astronomy, to date there is no definitive electromagnetic evidence for sub-parsec supermassive binary black holes at cosmological distances. We will obtain three-band radio spectra of six promising SMBHB candidates. These six were selected from 80,000 quasars in the Sloan Digital Sky Survey to have anomalous spectral energy distributions best explained by a gap cleared in the accretion disk by the orbiting secondary black hole. Multi-frequency radio observations are required to remove contamination from synchrotron sources that peak in the far-to-mid-IR. We will use 6 orbits with HST to acquire simultaneous UV-NIR SEDs; only HST has the UV sensitivity require to remove potential ambiguity due to variability. With these observations, we will construct continuous SEDs observed at one time (removing ambiguity due to variability) and investigate whether the SEDs are in fact consistent with a gap in the accretion disk. Determining the fraction of binary black holes will help predict the level of the gravitational wave background that may soon be detected by Pulsar Timing Arrays. Massive Black Holes and their Hosts Galaxies 12 false true false false false false SUPPORTED GALAXY ACCRETION DISK QUASAR J2000 J2000 GALAXY ACCRETION DISK QUASAR J2000 J2000 GALAXY ACCRETION DISK QUASAR J2000 J2000 GALAXY ACCRETION DISK QUASAR RADIO GALAXY NO J2000 J2000 GALAXY ACCRETION DISK QUASAR RADIO GALAXY NO J2000 J2000 GALAXY ACCRETION DISK QUASAR RADIO GALAXY NO J2000 J2000 WFC3/IR Imaging No No F160W WFC3/UVIS Imaging No No F225W WFC3/UVIS Imaging No No F336W WFC3/UVIS Imaging No No F606W WFC3/UVIS Imaging No No F814W WFC3/IR Imaging No No F160W WFC3/UVIS Imaging No No F225W WFC3/UVIS Imaging No No F336W WFC3/UVIS Imaging No No F606W WFC3/UVIS Imaging No No F814W WFC3/IR Imaging No No F160W WFC3/UVIS Imaging No No F225W WFC3/UVIS Imaging No No F336W WFC3/UVIS Imaging No No F606W WFC3/UVIS Imaging No No F814W WFC3/IR Imaging No No F160W WFC3/UVIS Imaging No No F225W WFC3/UVIS Imaging No No F336W WFC3/UVIS Imaging No No F606W WFC3/UVIS Imaging No No F814W WFC3/IR Imaging No No F160W WFC3/UVIS Imaging No No F225W WFC3/UVIS Imaging No No F336W WFC3/UVIS Imaging No No F606W WFC3/UVIS Imaging No No F814W WFC3/IR Imaging No No F160W WFC3/UVIS Imaging No No F225W WFC3/UVIS Imaging No No F336W WFC3/UVIS Imaging No No F606W WFC3/UVIS Imaging No No F814W POS-TARG DITHER 0.572 LINE 0.365 false false 74.653 4 18.528 WFC3-IR-DITHER-BOX-MIN 1 false POS-TARG DITHER 0.135 LINE false false 3 46.84 WFC3-UVIS-DITHER-LINE-3PT 2 false The scheduling data was generated by CASM 24.2. CASM was run in Phase II mode. (Tic-Visit :proposal-id 14898 :visit-id "01" :proposal-version -1 :trans-version "20160601" :date "05-Dec-2016 11:43:19.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "29" :si-bright-earth-limb-angle 20.0 :data-volume 291216 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 14898 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 14898 :visit-id "01" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2970 :al-overhead-at-end 47 :internal-dur-at-end 355 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3307 :pcs-gap 0 ) true 1 0 The scheduling data was generated by CASM 24.2. CASM was run in Phase II mode. (Tic-Visit :proposal-id 14898 :visit-id "02" :proposal-version -1 :trans-version "20160601" :date "05-Dec-2016 11:45:17.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "29" :si-bright-earth-limb-angle 20.0 :data-volume 291216 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 14898 :visit-id "02" :obset-id "02" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 14898 :visit-id "02" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2931 :al-overhead-at-end 47 :internal-dur-at-end 355 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3267 :pcs-gap 0 ) true 1 0 The scheduling data was generated by CASM 24.2. CASM was run in Phase II mode. (Tic-Visit :proposal-id 14898 :visit-id "03" :proposal-version -1 :trans-version "20160601" :date "06-Dec-2016 13:54:39.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "29" :si-bright-earth-limb-angle 20.0 :data-volume 291216 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 14898 :visit-id "03" :obset-id "03" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 14898 :visit-id "03" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2868 :al-overhead-at-end 47 :internal-dur-at-end 355 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3210 :pcs-gap 0 ) false 1 0 The scheduling data was generated by CASM 24.2. CASM was run in Phase II mode. (Tic-Visit :proposal-id 14898 :visit-id "04" :proposal-version -1 :trans-version "20160601" :date "05-Dec-2016 11:48:02.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "29" :si-bright-earth-limb-angle 20.0 :data-volume 291216 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 14898 :visit-id "04" :obset-id "04" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 14898 :visit-id "04" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2880 :al-overhead-at-end 47 :internal-dur-at-end 355 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3222 :pcs-gap 0 ) true 1 0 The scheduling data was generated by CASM 24.2. CASM was run in Phase II mode. (Tic-Visit :proposal-id 14898 :visit-id "05" :proposal-version -1 :trans-version "20160601" :date "05-Dec-2016 11:49:00.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "29" :si-bright-earth-limb-angle 20.0 :data-volume 291216 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 14898 :visit-id "05" :obset-id "05" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 14898 :visit-id "05" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2904 :al-overhead-at-end 47 :internal-dur-at-end 355 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3245 :pcs-gap 0 ) true 1 0 The scheduling data was generated by CASM 24.2. CASM was run in Phase II mode. (Tic-Visit :proposal-id 14898 :visit-id "06" :proposal-version -1 :trans-version "20160601" :date "05-Dec-2016 11:41:48.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "29" :si-bright-earth-limb-angle 20.0 :data-volume 291216 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 14898 :visit-id "06" :obset-id "06" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 14898 :visit-id "06" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2874 :al-overhead-at-end 47 :internal-dur-at-end 355 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3210 :pcs-gap 0 ) true 1 0