0 Resubmitting due to change in scheduling windows after safing. Moved second visit to 6 months after to have 180 degree roll. -736786295 ----- Attempting Submission 1 (Fri May 14 20:08:43 GMT 2021) ----- HST Phase II Proposal 16512 successfully submitted. Receipt: # 16512-1 ----- Attempting Submission 2 (Mon Aug 02 23:57:53 GMT 2021) ----- WFC3/IR Time-Dependent Sensitivity in Staring Mode (Clusters) The WFC3/IR detector photometric sensitivity is typically characterized by the measurement of isolated, standard spectrophotometric white dwarf stars. To supplement those observations, we seek to measure fluxes of hundreds of stars in stellar clusters over time, to achieve higher precision than using a single star. In this program, we propose to repeat observations from previous observations of M4 (Program 14725) to mitigate effects from different observation configurations. We propose two visits of WFC3/IR observations of M4. Both visits will be executed with the same exposure parameters, but will be scheduled approximately 3 months apart, to best sample the time dependence of the sensitivity withtin the window in which the target is visible. Each visit will be composed of 4 exposures, the first two in F110W and the latter two in F160W. The F110W images will use 14 samples with the SPARS50 sample sequence to match those taken in 14725. Due to the shorter orbit duration in 2021 (compared to 14725 in 2017), the latter two exposures will use an NSAMP of 13, to avoid visibility overrun. To mitigate persistence, POSTARGS of 2.5 arcseconds in X and Y will be used between exposures, to match the observations of 14725. 0 false false RESTRICTED STELLAR CLUSTER GLOBULAR CLUSTER J2000 /private/var/folders/2b/788l6xx92z9cqlwly6dwfb540001g1/T/OPVisit6599688356523261391.xml The scheduling data was generated by CASM 29.0. CASM was run in Phase II mode. (Tic-Visit :proposal-id 16512 :visit-id "01" :proposal-version -1 :trans-version "20200619" :date "27-Jul-2021 19:16:56.0" :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 1009712 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 16512 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 16512 :visit-id "01" :orbit-number 1 :pcs-time 383 :si-vis-utilization 2761 :al-overhead-at-end 0 :internal-dur-at-end 481 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3165 :pcs-gap 0 ) true 1 0 /private/var/folders/2b/788l6xx92z9cqlwly6dwfb540001g1/T/OPVisit4632697071938548275.xml The scheduling data was generated by CASM 29.0. CASM was run in Phase II mode. (Tic-Visit :proposal-id 16512 :visit-id "02" :proposal-version -1 :trans-version "20200619" :date "27-Jul-2021 19:16:53.0" :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 1009712 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 16512 :visit-id "02" :obset-id "02" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 16512 :visit-id "02" :orbit-number 1 :pcs-time 383 :si-vis-utilization 2761 :al-overhead-at-end 0 :internal-dur-at-end 481 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3165 :pcs-gap 0 ) true 1 0