0 Assigned ID: 7586 ----- Attempting Submission 1 (Thu Apr 16 19:50:09 GMT 2026) ----- Could not connect to APT Status Server This is a proposal focusing on the continuum polarization comparison in three different bands, g, r and i. The expected continuum polarization level could be 1-3 %. I chose proper exposure time to make the different band show similar SNR. I used the same exposure time for different polarization PA set up. I used 2-point dither to deal with cosmic ray and improve the sampling. -724112970 ----- Attempting Submission 1 (Fri Aug 14 13:59:31 GMT 2026) ----- The phase 1 has a warning that APT could not connect to the APT Status Server when the Phase I proposal information was loaded. This problem was solved but the warning cannot be deleted. Probing the Origin of the UV Continuum in Local LRD Analogs with HST Polarimetry Little Red Dots (LRDs) discovered by JWST may represent a key phase of early black hole and galaxy growth, yet their physical nature remains uncertain. A promising framework invokes an accreting black hole embedded in a dense gas envelope, which can explain many of the key observed properties of LRDs from the optical to the infrared. However, the origin of the rest-UV continuum remains unresolved: it may arise from a compact nuclear stellar population, or from AGN radiation escaping through a clumpy envelope after multiple scatterings. We propose HST/ACS imaging polarimetry for three recently identified local LRD analogs at redshifts of 0.1--0.2. Using F475W, F606W and F775W, we will measure the nuclear polarization on the blue and red sides of the Balmer break while minimizing the extended host-galaxy dilution through HST's high spatial resolution. A significant polarization excess in the blue continuum would provide strong evidence for scattered AGN light and support a role for electron scattering in shaping LRD spectra. This program will provide the first direct polarimetric constraint on the origin of the UV continuum in LRD analogs and help assess how reliably the physical properties of high-redshift LRDs can be inferred. Polarimetric observation using ACS/WFC S. Wang has extensive experience in AGN virial black hole mass estimation using reverberation mapping, and has experience with HST in the past. S. Hoenig has extensive expertise in dust physics and AGN black hole mass estimation and will help guide the physical interpretation of the observations. C. Knigge has extensive experience in the use of space telescopes and in simulations of accreting systems for interpreting observational data. He will provide valuable support in the scientific interpretation of the results. J.-W. Lyu focuses on AGN and galaxies across the cosmic time using multi-wavelength data, especially in the infrared. He has experience with space-based imaging and spectroscopy, and his work broadly explores the physical properties of dust-obscured nuclear regions and their connection to host galaxies. M. Tang has extensive experience with spectroscopy and imaging of distant galaxies including LRDs using ground-based and JWST data. S. Tang is an expert in quasar-host galaxy decomposition. He has extensive experience in studying the morphologies of quasar host galaxies using ground-based imaging data. M. Banerji is an expert in heavily reddened and unobscured quasars and their host galaxies, and will provide important insight into the scientific interpretation. Supermassive Black Holes and Active Galaxies Galaxies 6 false false false false false false false SUPPORTED GALAXY QSO J2000 J2000 GALAXY QSO J2000 J2000 GALAXY QSO The PM is within error = 0 J2000 J2000 ACS/WFC Imaging No Yes F475W ACS/WFC Imaging No Yes F606W ACS/WFC Imaging No Yes F775W ACS/WFC Imaging No Yes F475W ACS/WFC Imaging No Yes F606W ACS/WFC Imaging No Yes F775W ACS/WFC Imaging No Yes F475W ACS/WFC Imaging No Yes F606W ACS/WFC Imaging No Yes F775W POS-TARG DITHER 1 LINE false false 2 0 LINE 2 false /private/var/folders/26/zhpq7fdx2k1_w__qcchmm8380000gn/T/OPVisit17375980356574208387.xml The scheduling data was generated by CASM 34.2. CASM was run in Phase II mode. (Tic-Visit :proposal-id 18423 :visit-id "01" :proposal-version -1 :trans-version "20260618" :date "14-Aug-2026 15:58:21.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 3 :saa-model "27" :si-bright-earth-limb-angle 20.0 :data-volume 1279392 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 18423 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 18423 :visit-id "01" :orbit-number 1 :pcs-time 301 :si-vis-utilization 2673 :al-overhead-at-end 0 :internal-dur-at-end 0 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 2977 :pcs-gap 0 ) (Tic-Orbit :proposal-id 18423 :visit-id "01" :orbit-number 2 :pcs-time 301 :si-vis-utilization 2674 :al-overhead-at-end 0 :internal-dur-at-end 0 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 2977 :pcs-gap 0 ) (Tic-Orbit :proposal-id 18423 :visit-id "01" :orbit-number 3 :pcs-time 301 :si-vis-utilization 2634 :al-overhead-at-end 0 :internal-dur-at-end 269 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 2977 :pcs-gap 0 ) true 3 0 /private/var/folders/26/zhpq7fdx2k1_w__qcchmm8380000gn/T/OPVisit3631434857796543999.xml The scheduling data was generated by CASM 34.2. CASM was run in Phase II mode. (Tic-Visit :proposal-id 18423 :visit-id "02" :proposal-version -1 :trans-version "20260618" :date "14-Aug-2026 15:58:22.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 3 :saa-model "27" :si-bright-earth-limb-angle 20.0 :data-volume 1279392 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 18423 :visit-id "02" :obset-id "02" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 18423 :visit-id "02" :orbit-number 1 :pcs-time 301 :si-vis-utilization 2673 :al-overhead-at-end 0 :internal-dur-at-end 0 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 2974 :pcs-gap 0 ) (Tic-Orbit :proposal-id 18423 :visit-id "02" :orbit-number 2 :pcs-time 301 :si-vis-utilization 2654 :al-overhead-at-end 0 :internal-dur-at-end 0 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 2974 :pcs-gap 0 ) (Tic-Orbit :proposal-id 18423 :visit-id "02" :orbit-number 3 :pcs-time 301 :si-vis-utilization 2654 :al-overhead-at-end 0 :internal-dur-at-end 269 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 2974 :pcs-gap 0 ) true 3 0 /private/var/folders/26/zhpq7fdx2k1_w__qcchmm8380000gn/T/OPVisit3967900279604507038.xml The scheduling data was generated by CASM 34.2. CASM was run in Phase II mode. (Tic-Visit :proposal-id 18423 :visit-id "03" :proposal-version -1 :trans-version "20260618" :date "14-Aug-2026 15:58:24.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 3 :saa-model "27" :si-bright-earth-limb-angle 20.0 :data-volume 1279392 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 18423 :visit-id "03" :obset-id "03" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 18423 :visit-id "03" :orbit-number 1 :pcs-time 301 :si-vis-utilization 2673 :al-overhead-at-end 0 :internal-dur-at-end 0 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 2977 :pcs-gap 0 ) (Tic-Orbit :proposal-id 18423 :visit-id "03" :orbit-number 2 :pcs-time 301 :si-vis-utilization 2674 :al-overhead-at-end 0 :internal-dur-at-end 0 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 2977 :pcs-gap 0 ) (Tic-Orbit :proposal-id 18423 :visit-id "03" :orbit-number 3 :pcs-time 301 :si-vis-utilization 2634 :al-overhead-at-end 0 :internal-dur-at-end 269 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 2977 :pcs-gap 0 ) true 3 0