Science Keywords: Select from 2 to 5 items. Science Keywords is a required field. US Admin CoI is a required field. 0 Assigned ID: 1507 ----- Attempting Submission 1 (Fri Aug 11 17:01:54 GMT 2017) ----- Joint Chandra/HST Proposal loads It was necessary to add a quite restricted ORIENT set to move the jet region away from diffraction spikes and charge bleeding. This restricts observations to about 18 days per year. We would be very grateful for a check that the ORIENT is acceptable, in moving the position angle range 0 - 35 deg away from the diffraction spikes and quasar core columns. A POS TARG offset of 10 arcsec is used to move the quasar itself further away from the WFC3/UVIS chip gap. Many attempts were made to use the WFC3-UVIS-DITHER-LINE-3PT pattern with shorter exposures to gain additional redundancy in the F814W filter, but none fitted within the envelope of a single orbit, hence two patterns are used. -1471793082 ----- Attempting Submission 1 (Fri Sep 08 15:03:22 GMT 2017) ----- We propose a 130-ks observation with Chandra of the exceptional kpc-scale X-ray jet associated with a radio-loud quasar at redshift 3.689. This quasar was selected from a radio/X-ray archival study based on its unusual X-ray brightness and the strong difference between its X-ray and radio morphologies. The existing 3.3-ks Chandra exposure shows a ribbon-like X-ray structure offset from the radio jet, and an unusually high X-ray jet to core flux ratio. We wish to support the new Chandra observation with short JVLA and HST observations. The modeling possible from the new data will be important for the debate concerning a synchrotron or inverse Compton origin for the X-rays of high-redshift quasar jets, and should strongly constrain the source energetics. We will use one HST orbit to image quasar J1421-0643 using WFC3/UVIS to constrain the radio-to-X-ray spectrum of its unusual jet. 22.5 min of exposure with the F555W filter should detect the jet with signal/noise > 3 in 0.4 arcsec detection cells. 16.3 min of exposure with the F814W filter will provide independent confirmation of any faint structure and constrain the jet spectral index. WFC3/UVIS is preferred to ACS to avoid two bright stars in the neighbourhood of J1421-0643. We use dither patterns WFC3-UVIS-DITHER-LINE-3PT with F555W and WFC3-UVIS-DITHER-LINE with F814W to remove hot columns and cosmic rays in the data. Post-observation FLASH=2 is used to improve CTE for F814W. ORIENT is used to move the jet (which lies in position angle 0 - 35 deg from the quasar core, and extends 5 arcsec) away from the diffraction spikes and columns that might bleed charge from the quasar core. POS TARG is used to move the quasar 10 arcsec further from the chip gap so that its full environment is well imaged. Massive Black Holes And Their Host Galaxies 6 false false false false false false SUPPORTED GALAXY QUASAR NO Quasar core is point-like. Faint jet-like structure in position angle range 0 - 35 deg, extending 5 arcsec, is main target. J2000 J2000 WFC3/UVIS Imaging No No F555W WFC3/UVIS Imaging No No F814W POS-TARG DITHER 0.145 Dither for CR removal LINE false false 2 46.84 WFC3-UVIS-DITHER-LINE 1 false POS-TARG DITHER 0.135 Dither for CR removal. LINE false false 3 46.84 WFC3-UVIS-DITHER-LINE-3PT 2 false 1504881540002 /Users/phmb/HST/OP-cache/15376_phase_ii_v9-v01.xml The scheduling data was generated by CASM 25.2. CASM was run in Phase II mode. Main observation in F555W. Subsidiary/confirmation observation in F814W. (Tic-Visit :proposal-id 15376 :visit-id "01" :proposal-version -1 :trans-version "20170613" :date "08-Sep-2017 15:38:59.0" :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 1443744 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 15376 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 15376 :visit-id "01" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2870 :al-overhead-at-end 119 :internal-dur-at-end 668 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3205 :pcs-gap 0 ) true 1 0 Primary science exposure Confirmation exposure, spectral information.