Scientific Category is a required field. Science Keywords is a required field. Science Keywords: Select from 3 to 5 items. Please specify your scheduling constraints or 'No Constraints' on all Observation forms. Please specify your scheduling constraints or 'No Constraints' on all Observation forms. Please specify your scheduling constraints or 'No Constraints' on all Observation forms. 0 Assigned ID: 1162 ----- Attempting Submission 1 (Wed Sep 09 11:10:15 GMT 2015) ----- Joint Chandra/HST Proposal Edited Visit 3 so it is comprised of two identical exposure sequences. -1979571219 ----- Attempting Submission 1 (Tue Oct 13 00:21:40 GMT 2015) ----- HST Phase II Proposal 14356 (14356_phaseII.apt) successfully submitted. Receipt: # 14356-1 ----- Attempting Submission 2 (Wed Oct 21 17:51:39 GMT 2015) ----- Multiwavelength Characterization of Candidate Black Holes in Nearby Dwarf Galaxies The properties of the first black holes (BH) that 'seeded' the growth of supermassive BHs are poorly understood, even though these seed BHs represent critical boundary conditions for models of BH/galaxy (co)-evolution. Local dwarf galaxies provide our best opportunity to obtain observational constraints. Here, we propose multiwavelength Chandra, HST and VLA observations to investigate the nature of candidate nuclear BHs in three nearby dwarfs. Our targets were recently identified within the Chandra archive, and they represent a population missed by surveys at optical wavelengths. These observations will place new constraints on seed BH masses, and they will help inform future multiwavelength surveys for BHs in the nuclei of dwarf galaxies. Our primary HST goal is isolate the optical nucleus for our three target dwarf galaxies. To study our targets, we will use the F110W filter on the WFC3 IR channel and the F606W filter on the WFC3 UVIS channel. The IR filter traces the older stellar population, providing our best probe of the galaxy morphology, while the UVIS imaging will allow us to obtain color information and isolate star forming regions. For targets SDSS J1221 and MRK 1434, we will use the following observing strategy: IR/F110W: With 600s exposures in the F110W filter, we will reach a sensitivity of mu_r=23 mag/arcsec^2 at S/N>10 per pixel, according to the online WFC3 exposure time calculator (our experience is that we can go one magnitude deeper through radial profile averaging). We will divide the 600s exposures into four dithered positions to improve the pixel sampling (and reject bad pixels), using the STEP25 timing sequence with NSAMP=10 (150s per exposure), and using the IRSUB512 subarray to avoid buffer dumps. UVIS/F606W: For the F606W filter, with ~1900 sec exposures we can reach a sensitivity better than mu_r=23 mag/arcsec^2, with a S/N~9 per 3x3 pixel box (similar to a 1x1 pixel area in the IR channel). SDSS J1213 is significantly fainter than the other two targets, with a central surface brightness mu_0,r ~ 23.8 mag/arcsec^2. For this source, we will forego the F606W filter, and take a longer ~2600s exposure in only the F110W IR filter. This will provide a sensitivity of mu_r ~ 24-25 mag/arcsec^2, which will be sufficient. For that source, we will use two exposure sequences of 4 dither points each. The first will use the STEP100 sequence with NSAMP = 12 (~600s per exposure). The second will use the STEP100 sequence with NSAMP = 6 (~50s per exposure) for a total exposure time of ~2600s. No subarray will be necessary. We will easily meet our main HST goal of isolating the optical center. AGN/QUASARS 12 false false false false SUPPORTED GALAXY DWARF COMPACT This object was generated by the targetselector and retrieved from the SIMBAD database. J2000 J2000 GALAXY AMORPHOUS IRREGULAR DWARF COMPACT J2000 J2000 GALAXY DWARF COMPACT J2000 J2000 WFC3/IR Imaging No No F110W WFC3/UVIS Imaging No No F606W WFC3/IR Imaging No No F110W WFC3/IR Imaging No No F110W WFC3/UVIS Imaging No No F606W 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 0.173 LINE 0.112 false false 81.785 4 23.884 WFC3-UVIS-DITHER-BOX 2 false /Users/vbaldas/Documents/Proposals/HST_Plotkin/OP-cache/14356_phaseII-v01.xml The scheduling data was generated by CASM 23.2. CASM was run in Phase II mode. (Tic-Visit :proposal-id 14356 :visit-id "01" :proposal-version -1 :trans-version "20150609" :date "12-Oct-2015 20:15:17.0" :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 1354944 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 14356 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 14356 :visit-id "01" :orbit-number 1 :pcs-time 333 :si-vis-utilization 3123 :al-overhead-at-end 0 :internal-dur-at-end 615 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3456 :pcs-gap 0 ) true 1 0 /Users/vbaldas/Documents/Proposals/HST_Plotkin/OP-cache/14356_phaseII-v02.xml The scheduling data was generated by CASM 23.2. CASM was run in Phase II mode. (Tic-Visit :proposal-id 14356 :visit-id "02" :proposal-version -1 :trans-version "20150609" :date "12-Oct-2015 20:15:21.0" :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 1354944 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 14356 :visit-id "02" :obset-id "02" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 14356 :visit-id "02" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2887 :al-overhead-at-end 0 :internal-dur-at-end 615 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3221 :pcs-gap 0 ) true 1 0 /private/var/folders/_9/0dy5rdcs7_l2pg2dp_wmkhg02ys67s/T/OPVisit7936853081220055244.xml The scheduling data was generated by CASM 23.2. CASM was run in Phase II mode. (Tic-Visit :proposal-id 14356 :visit-id "03" :proposal-version -1 :trans-version "20150609" :date "21-Oct-2015 13:45:35.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "30" :si-bright-earth-limb-angle 20.0 :data-volume 2089072 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 14356 :visit-id "03" :obset-id "03" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 14356 :visit-id "03" :orbit-number 1 :pcs-time 333 :si-vis-utilization 3020 :al-overhead-at-end 0 :internal-dur-at-end 652 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3403 :pcs-gap 0 ) true 1 0