0 ----- Attempting Submission 1 (Wed Feb 25 22:05:40 GMT 2015) ----- HST Phase II Proposal 14047 (mrk709_hst_phaseII.apt.2015_02_23_19_55.aptbackup.2015_02_24_21_52.aptbackup.2015_02_25_15_00.aptbackup) successfully submitted. Receipt: # 14047-1 ----- Attempting Submission 2 (Wed Feb 25 22:06:17 GMT 2015) ----- The incidence and properties of present-day dwarf galaxies hosting massive black holes (BHs) can provide important constraints on the origin of high-redshift BH seeds. Reines et al. (2014) have recently identified a candidate AGN in the low-metallicity dwarf galaxy pair Mrk 709. The case for an accreting massive BH is strong (co-spatial central VLA and Chandra point sources), but not watertight. Moreover, very little is known about the environment in which the BH is growing. The primary goal of our proposal is to confirm (or refute) the presence of this candidate AGN by using the HSA (VLBA+VLA+GBT) to detect a compact, high brightness temperature radio core. We also aim to characterize the host galaxy using HST optical and near-IR observations. In particular, we will determine if the AGN lives in a bulge and investigate the star formation in the immediate vicinity of the BH. Confirming the AGN and probing any potential impact on its host galaxy is only possible using deep, high-resolution observations with the HSA and HST. The results from these observations will have important implications for the birth and growth of the first high-redshift BHs. We will obtain optical and near-IR observations of Mrk 709 with WFC3. The galaxy will be imaged in 3 filters: IR F110W, UVIS F680N, and UVIS F621M. For each filter, we will obtain 4 dithered exposures to facilitate cosmic-ray rejection, avoid bad pixels, and improve the PSF sampling. According to the WFC3/IR exposure time calculator, we need ~ 7 minutes in F110W to reach a 10-sigma surface-brightness sensitivity of mu_r ~ 23 mag arcsec^2 in a given pixel, which will allow us to adequately decouple bulge and disk components on small scales. We will use the timing sequence STEP25 with NSAMP=9 (~100 s per exposure) and use the IRSUB512 subarray to avoid buffer dumps. Our target galaxy is quite compact so using a subarray will not compromise our science or limit our sky subtraction. Requisite exposure times in F680N (redshifted H-alpha filter) and F621M (~r-band continuum) are based on the SDSS spectrum of Mrk 709 S. In this 3" aperture, we measure an H-alpha flux of 8.0 x 10^-14 erg/s/cm^2 and a continuum flux density of F6200 = 4.5 x 10^-16 erg/s/cm^2/A. To reach a signal-to-noise ratio of ~20-25 per pixel, the WFC3/UVIS exposure time calculator suggests we need ~25 and ~30 minutes in F680N and F621M, respectively. We will use the 2k x 2k subarray with chip 2 to avoid buffer dumps and reduce readout overhead. We will also use a post-flash to avoid poor charge transfer efficiency. AGN/QUASARS 12 Regular false false 5 false false false SUPPORTED GALAXY DWARF COMPACT STARBURST J2000 J2000 R (Cousins) = 15.65 mag WFC3/UVIS Imaging No No F680N POS-TARG DITHER 0.173 LINE 0.112 false false 81.785 4 23.884 WFC3-UVIS-DITHER-BOX 1 false POS-TARG DITHER 0.572 LINE 0.365 false false 74.653 4 18.528 WFC3-IR-DITHER-BOX-MIN 2 false 1424895139984 /Users/reines/Proposals/VLBA/Mrk709/HSTphaseII/OP-cache/mrk709_hst_phaseII-v01.xml The scheduling data was generated by CASM 23.0. CASM was run in Phase II mode. (Tic-Visit :proposal-id 14047 :visit-id "01" :proposal-version -1 :trans-version "20150128" :date "25-Feb-2015 15:12:19.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 2 :saa-model "29" :si-bright-earth-limb-angle 20.0 :data-volume 744864 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 14047 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 14047 :visit-id "01" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2898 :al-overhead-at-end 170 :internal-dur-at-end 0 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3231 :pcs-gap 0 ) (Tic-Orbit :proposal-id 14047 :visit-id "01" :orbit-number 2 :pcs-time 222 :si-vis-utilization 3007 :al-overhead-at-end 0 :internal-dur-at-end 588 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3231 :pcs-gap 0 ) true 2 0