0 Assigned ID: 1642 ----- Attempting Submission 1 (Fri Mar 09 18:11:01 GMT 2018) ----- POS TARG & PATTERN should be used carefully with ACS ramp filters as central wavelengths & transmission efficiencies vary within the apertures. POS TARG & PATTERN should be used carefully with ACS ramp filters as central wavelengths & transmission efficiencies vary within the apertures. 0 ----- Attempting Submission 1 (Thu Mar 15 16:18:49 GMT 2018) ----- We understand that we need to be carefully when dithering with ramp filter. We have coordinated with our contact scientist about it. Our target is very compact and we will not getting out of the region of constant wavelength with the 3-points line dither. The Most Distant Gravitationally Lensed Quasar at z=6.5 We propose to use two-orbit HST/ACS imaging to confirm the highest-redshift gravitationally lensed quasar yet know at z=6.5. The lack of strongly lensed quasar at high redshift has been a long-standing puzzle. The highest redshift strongly lensed quasar known is only at z=4.8, and two large HST SNAP surveys yielded no multiply imaged quasars at z>4 among more than 200 targets. Recently, we discovered a ultra-luminous quasar at z=6.5. With M1450=-29.5, it is the most luminous known object at z>6. Close examination of the discovery spectrum shows a faint trace over the wavelength covered by strong IGM absorption, suggesting the presence of a foreground galaxy. Ground-based AO imaging with 0.2'' resolution shows that the object is marginally resolved beyond the observed PSF. A model with > 2 components produces a significantly improved fit, suggesting a compact Einstein ring size of 0.2''. The presence of a small proximity zone and the implied super-Eddington BH accretion rate further suggest that the intrinsic quasar luminosity is much lower. However, the existing ground-based images are not able to fully resolve the system. HST resolution is needed. The proposed modest ACS observations will definitely resolve the system and characterize the lensing geometry. If confirmed, this would be the first known quasar lens at reionzation epoch, providing a unique opportunity to constrain quasar lens model, measure quasar host, and probe the small scale structure of reionization-era IGM through multiple sightlines. The current visibility window for this object ends in early April. A timely observation will allow prompt publication and plan for JWST Cycle-1 followup observations. We'll perform FR782N and FR853N observations on a lensed quasar at z=6.50. Our ground based AO imaging suggests the Einstein ring is about 0.2". In order to get as high resolution possible, we will use the ramp filter FR782N centered at Lyman-beta emission line to detect lens images with sub-pixel dithering. In order to detect the forground lensing galaxy, we will use FR853N centered at the quasar Gunn-Peterson trough, where quasar has zero flux. In order to balace the cosmic ray rejection and CTE correction, we choose to use 3 points line dither and not include postflash for both filters. The individual exposure is 782s. Cosmology Massive Black Holes And Their Host Galaxies 3 SUPPORTED GALAXY GRAVITATIONAL LENS HIGH REDSHIFT GALAXY QUASAR YES This object is undetected in V-band (fainter 24 magnitude). J2000 J2000 z_AB=19.5 ACS/WFC RampFilter No No FR782N ACS/WFC RampFilter No No FR853N POS-TARG DITHER 0.170 LINE false false 3 47.23 ACS-WFC-DITHER-LINE 2 false The scheduling data was generated by CASM 25.2. CASM was run in Phase II mode. (Tic-Visit :proposal-id 15453 :visit-id "01" :proposal-version -1 :trans-version "20171009" :date "20-Mar-2018 11:56:32.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "27" :si-bright-earth-limb-angle 20.0 :data-volume 852672 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 15453 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 15453 :visit-id "01" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2882 :al-overhead-at-end 0 :internal-dur-at-end 347 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3216 :pcs-gap 0 ) false 1 0 The scheduling data was generated by CASM 25.2. CASM was run in Phase II mode. (Tic-Visit :proposal-id 15453 :visit-id "02" :proposal-version -1 :trans-version "20171009" :date "20-Mar-2018 11:56:32.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "27" :si-bright-earth-limb-angle 20.0 :data-volume 852672 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 15453 :visit-id "02" :obset-id "02" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 15453 :visit-id "02" :orbit-number 1 :pcs-time 333 :si-vis-utilization 2882 :al-overhead-at-end 0 :internal-dur-at-end 347 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3216 :pcs-gap 0 ) false 1 0