We propose for HST/WFC3 UVIS imaging of tidal disruption event candidate PS1-10jh, a UV/optical transient which is currently the most convincing example of an accretion-powered flare from the tidal disruption of a star by an otherwise dormant supermassive black hole. The proposed observations will critically test the tidal disruption event scenario, provide essential information for modeling the parameters of the event, and constrain theoretical models for the evolution of the accreting debris disk, by 1) determining the flare-nucleus separation much more accurately than ground-based observations, 2) measuring the late-time NUV emission from the flare, and 3) obtaining more accurate independent constraints on the central black hole mass. We are using 3 orbits of HST/WFC3 UVIS observations to image PS1-10jh and its host galaxy in the F225W and F625W filters. We will take a total of 3.6 ksec of exposure in each filter, using hte box-dither pattern (WFC3-UVIS-DITHER-BOX) for cosmic-ray removal and improved sampling of the point spread function. AGN/QUASARS 12 false false 0.0 0.0 false false false SUPPORTED GALAXY ACCRETION DISK BULGE ELLIPTICAL NUCLEUS J2000 J2000 WFC3/UVIS Imaging No No F225W WFC3/UVIS Imaging No No F625W POS-TARG DITHER 0.173 LINE 0.112 false false 81.785 4 23.884 WFC3-UVIS-DITHER-BOX 1 false The scheduling data was generated by CASM 21.2. CASM was run in Phase II mode. (Tic-Visit :proposal-id 13371 :visit-id "01" :proposal-version -1 :trans-version "20130919" :date "08-Oct-2013 13:50:36.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 3 :saa-model "29" :si-bright-earth-limb-angle 20.0 :data-volume 2309952 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 13371 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 13371 :visit-id "01" :orbit-number 1 :pcs-time 333 :si-vis-utilization 3097 :al-overhead-at-end 122 :internal-dur-at-end 0 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3430 :pcs-gap 0 ) (Tic-Orbit :proposal-id 13371 :visit-id "01" :orbit-number 2 :pcs-time 222 :si-vis-utilization 3208 :al-overhead-at-end 116 :internal-dur-at-end 0 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3430 :pcs-gap 0 ) (Tic-Orbit :proposal-id 13371 :visit-id "01" :orbit-number 3 :pcs-time 222 :si-vis-utilization 3208 :al-overhead-at-end 116 :internal-dur-at-end 668 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3430 :pcs-gap 0 ) true 3 0