0 Assigned ID: 3529 ----- Attempting Submission 1 (Fri Mar 25 20:45:58 GMT 2022) ----- HST Phase I Proposal 3529 successfully submitted. Receipt: # 3529-1 ----- Attempting Submission 2 (Fri Mar 25 23:03:39 GMT 2022) ----- HST Phase I Proposal 3529 successfully submitted. Receipt: # 3529-2 ----- Attempting Submission 3 (Fri Mar 25 23:20:53 GMT 2022) ----- Changed the POS TARG Y offset to -50'' to place the target in the center of chip 2 for WFC3/UVIS visit. Resubmitting after running the orbit and visit planner. -1826544172 ----- Attempting Submission 1 (Fri Jul 15 02:43:02 GMT 2022) ----- ----- Attempting Submission 2 (Thu Nov 03 01:24:22 GMT 2022) ----- HST Phase II Proposal 17082 successfully submitted. Receipt: # 17082-2 ----- Attempting Submission 3 (Thu Nov 03 03:33:14 GMT 2022) ----- ----- Attempting Submission 4 (Sat Dec 03 04:09:14 GMT 2022) ----- The first UVIS visit has been completed and I cannot run the visit and orbit planner for it anymore. Ultrahot Jupiters (UHJs) provide us with an exciting opportunity to probe the refractory content of exoplanetary atmospheres. These planets are hot enough to retain species such as iron and silicon in gaseous phase, which contribute significant opacity in the optical and near-IR but especially in near-UV. By observing a planet's transmission spectrum across this wide wavelength range with HST, we can measure the refractory abundance in its atmosphere. Additionally, we can characterize the refractory-to-volatile ratio of the planet by simultaneously measuring the water abundance in the near-IR. The joint characterization of refractory and volatile abundances can place significantly tighter constraints on the origin of gas giant planets than volatiles alone can. This technique has been used to characterize two UHJs (WASP-121b and WASP-178b) so far but both of them have polar orbits around their host stars. Here, we propose to observe the UHJ KELT-20b (Teq = 2260 K) that orbits a very bright and hot star (V mag = 7.6, Teff = 8720 K) and yet has a projected obliquity of 0.6 +/- 4 degrees. This extremely rare dynamical configuration for KELT-20b points to a formation and migration history that is potentially different from its compatriots. We will obtain a comprehensive transmission spectrum of KELT-20b and characterize both its refractory and water content by observing it with the WFC3 instrument in the UVIS, G102, and G141 bandpasses. With our proposed observations, we can strongly distinguish between different formation scenarios, evaluate the role of rainout, and determine if KELT-20b's distinct dynamical configuration is reflected in its atmospheric composition. This program includes four separate transit observations of KELT-20b. Two transits will be taken with UVIS/G280 (five orbits/transit), and one transit each with WFC3/G102 and WFC3/G141 (six orbits/transit). Dr. Chachan is an expert in linking the properties of protoplanetary disks, planet formation, and planetary atmospheres. He has prior experience in reducing and analyzing HST and Spitzer data as well as atmospheric modeling and retrievals. He is also the co-creator of a publicly available and widely used retrieval package (PLATON). Dr. Knutson is a leading exoplanetary scientist with extensive experience with data from both space- and ground-based observatories. She has published HST transmission spectra for multiple transiting planets including HD 209458b (Knutson et al. 2007), GJ 436b (Knutson et al. 2014a), and HD 97658b (Knutson et al. 2014b). She is a co-I on several large/treasury programs with HST focused on atmospheric characterization of transiting planets (GO 13467, PI Deming; GO 13665, PI Benneke; GO 14767, PI Sing). Dr. Lothringer is an expert in both observing with HST, as well as atmosphere modeling and retrieval with PHOENIX. Dr. Lothringer has extensive experience studying the highly irradiated class of ultra-hot Jupiters and is PI of 4 recent HST programs and 2 upcoming JWST programs. Dr. Spake is an expert in the analysis and interpretation of transiting exoplanets with space-based observatories, leading 3 successful HST proposals, 1 JWST proposal, and 1 Spitzer proposal. Exoplanets and Exoplanet Formation 6 false false true false false false false AVAILABLE STAR A0-A3 V-IV This object was generated by the targetselector and retrieved from the SIMBAD database. J2000 J2000 WFC3/UVIS Spectroscopic No No G280 WFC3/IR Spectroscopic No No G102 WFC3/IR Spectroscopic No No G141 1670018201275 The scheduling data was generated by CASM 30.3. CASM was run in Phase II mode. /Users/ychachan/Research/Projects/KELT-20/hst_2022_Kelt-20b_proposal/phase_ii_file/Dec_update/OP-cache/kelt20b_phaseII-v04.xml All five orbits must be scheduled in a continuous block. For this bright target, we saturate the +1 order in 4.7 s. This leads to a very low observing efficiency, and is problematic because UVIS has a shutter timing jitter of 0.004 rms, which leads to a photometric error of 0.004/integration time. In order to mitigate for this shutter timing jitter, we elect to use the -1 spectral order instead. This order has a peak throughput that is a factor of ~5 lower than the +1 order (Fig. 8.3 in the WFC3 Instrument Handbook and Fig. 1 of Wakeford et al. 2020). We therefore increase our integration time by a factor of five, to 23.5 s. This saturates the +1 order, but results in an equivalent number of photons in the -1 order as we would have obtained in the +1 order with a 4.7 s exposure. This test uses a subarray that is 100 pixels shorter than the one used by GO 16086, which is needed to ensure that the buffer dump occurs after the end of the visibility window in each orbit. It may be worth exploring an even smaller y axis range for the subarray, if that allows for additional exposures in each orbit. (Tic-Visit :proposal-id 17082 :visit-id "04" :proposal-version -1 :trans-version "20220630" :date "02-Dec-2022 16:55:05.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 5 :saa-model "29" :si-bright-earth-limb-angle 20.0 :data-volume 2214864 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 17082 :visit-id "04" :obset-id "04" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 17082 :visit-id "04" :orbit-number 1 :pcs-time 383 :si-vis-utilization 2364 :al-overhead-at-end 63 :internal-dur-at-end 517 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3180 :pcs-gap 0 ) (Tic-Orbit :proposal-id 17082 :visit-id "04" :orbit-number 2 :pcs-time 392 :si-vis-utilization 2355 :al-overhead-at-end 63 :internal-dur-at-end 517 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3180 :pcs-gap 0 ) (Tic-Orbit :proposal-id 17082 :visit-id "04" :orbit-number 3 :pcs-time 392 :si-vis-utilization 2355 :al-overhead-at-end 63 :internal-dur-at-end 517 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3180 :pcs-gap 0 ) (Tic-Orbit :proposal-id 17082 :visit-id "04" :orbit-number 4 :pcs-time 392 :si-vis-utilization 2355 :al-overhead-at-end 63 :internal-dur-at-end 517 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3180 :pcs-gap 0 ) (Tic-Orbit :proposal-id 17082 :visit-id "04" :orbit-number 5 :pcs-time 392 :si-vis-utilization 2355 :al-overhead-at-end 63 :internal-dur-at-end 629 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3180 :pcs-gap 0 ) true 5 0 Configured following the example in GO 16086. We use a subarray (SIZEAXIS1=2250 and SIZEAXIS2=590) to minimize data volume, and center the subarray readout on the zeroth order of G280 spectrum using CENTERAXIS1 and CENTERAXIS2. We also adopt FLASH=20 following the approach adopted in GO 16086 and discussed in the Instrument Science Report WFC3 2021-09. The specific value of 20 is the one recommended by the ETC. We needed to use a narrower filter than in GO 16086 to avoid saturating, we picked one with an equivalent central wavelength (F469N vs F467M). Detector chip 2. We include FLASH=20, as we anticipate < 1 e- of background per science exposure, in order to ensure maximum CTE. Detector chip 2. We include FLASH=20, as we anticipate < 1 e- of background per science exposure, in order to ensure maximum CTE. Detector chip 2. We include FLASH=20, as we anticipate < 1 e- of background per science exposure, in order to ensure maximum CTE. Detector chip 2. We include FLASH=20, as we anticipate < 1 e- of background per science exposure, in order to ensure maximum CTE. Detector chip 2. We include FLASH=20, as we anticipate < 1 e- of background per science exposure, in order to ensure maximum CTE. 1667418713651 The scheduling data was generated by CASM 30.3. CASM was run in Phase II mode. All five orbits must be scheduled in a continuous block. For this bright target, we saturate the +1 order in 4.7 s. This leads to a very low observing efficiency, and is problematic because UVIS has a shutter timing jitter of 0.004 rms, which leads to a photometric error of 0.004/integration time. In order to mitigate for this shutter timing jitter, we elect to use the -1 spectral order instead. This order has a peak throughput that is a factor of ~5 lower than the +1 order (Fig. 8.3 in the WFC3 Instrument Handbook and Fig. 1 of Wakeford et al. 2020). We therefore increase our integration time by a factor of five, to 23.5 s. This saturates the +1 order, but results in an equivalent number of photons in the -1 order as we would have obtained in the +1 order with a 4.7 s exposure. This test uses a subarray that is 100 pixels shorter than the one used by GO 16086, which is needed to ensure that the buffer dump occurs after the end of the visibility window in each orbit. It may be worth exploring an even smaller y axis range for the subarray, if that allows for additional exposures in each orbit. 1669208201000 53.739766400812414 (Tic-Visit :proposal-id 17082 :visit-id "05" :proposal-version -1 :trans-version "20220630" :date "02-Nov-2022 15:50:06.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 5 :saa-model "29" :si-bright-earth-limb-angle 20.0 :data-volume 2214864 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 17082 :visit-id "05" :obset-id "05" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 17082 :visit-id "05" :orbit-number 1 :pcs-time 383 :si-vis-utilization 2364 :al-overhead-at-end 63 :internal-dur-at-end 517 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3180 :pcs-gap 0 ) (Tic-Orbit :proposal-id 17082 :visit-id "05" :orbit-number 2 :pcs-time 392 :si-vis-utilization 2355 :al-overhead-at-end 63 :internal-dur-at-end 517 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3180 :pcs-gap 0 ) (Tic-Orbit :proposal-id 17082 :visit-id "05" :orbit-number 3 :pcs-time 392 :si-vis-utilization 2355 :al-overhead-at-end 63 :internal-dur-at-end 517 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3180 :pcs-gap 0 ) (Tic-Orbit :proposal-id 17082 :visit-id "05" :orbit-number 4 :pcs-time 392 :si-vis-utilization 2355 :al-overhead-at-end 63 :internal-dur-at-end 517 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3180 :pcs-gap 0 ) (Tic-Orbit :proposal-id 17082 :visit-id "05" :orbit-number 5 :pcs-time 392 :si-vis-utilization 2355 :al-overhead-at-end 63 :internal-dur-at-end 629 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3180 :pcs-gap 0 ) false 5 0 Configured following the example in GO 16086. We use a subarray (SIZEAXIS1=2250 and SIZEAXIS2=590) to minimize data volume, and center the subarray readout on the zeroth order of G280 spectrum using CENTERAXIS1 and CENTERAXIS2. We also adopt FLASH=20 following the approach adopted in GO 16086 and discussed in the Instrument Science Report WFC3 2021-09. The specific value of 20 is the one recommended by the ETC. We needed to use a narrower filter than in GO 16086 to avoid saturating, we picked one with an equivalent central wavelength (F469N vs F467M). Detector chip 2. We include FLASH=20, as we anticipate < 1 e- of background per science exposure, in order to ensure maximum CTE. Detector chip 2. We include FLASH=20, as we anticipate < 1 e- of background per science exposure, in order to ensure maximum CTE. Detector chip 2. We include FLASH=20, as we anticipate < 1 e- of background per science exposure, in order to ensure maximum CTE. Detector chip 2. We include FLASH=20, as we anticipate < 1 e- of background per science exposure, in order to ensure maximum CTE. Detector chip 2. We include FLASH=20, as we anticipate < 1 e- of background per science exposure, in order to ensure maximum CTE. 1670028135893 The scheduling data was generated by CASM 30.3. CASM was run in Phase II mode. /private/var/folders/x9/xxl0qz1j6170fjlsyns6n4x80000gn/T/OPVisit5234157297913198217.xml All six orbits must be scheduled in a continuous block. Visit patterned after GO 16307 (PI Fu), which observed a secondary eclipse of this same target with G141. The overall efficiency is only 51%, but this is needed in order to keep the maximum flux in an individual pixel < 28,000 electrons (recommendation from Wilkins et al. 2014 is fluxes below 30,000 electrons to avoid "hook" feature, but up to 40,000 seemed to work okay for HD 209458). Might consider if there are slightly slower scan rates/integration times that would result in a modestly higher peak electron flux but still stay below ~<35,000 electrons, but the gain in SNR is probably marginal and trades off against increased instrumental systematics. (Tic-Visit :proposal-id 17082 :visit-id "02" :proposal-version -1 :trans-version "20220630" :date "02-Dec-2022 19:40:25.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 6 :saa-model "30" :si-bright-earth-limb-angle 20.0 :data-volume 2713904 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 17082 :visit-id "02" :obset-id "02" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 17082 :visit-id "02" :orbit-number 1 :pcs-time 393 :si-vis-utilization 2272 :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 3025 :pcs-gap 0 ) (Tic-Orbit :proposal-id 17082 :visit-id "02" :orbit-number 2 :pcs-time 392 :si-vis-utilization 2260 :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 3025 :pcs-gap 0 ) (Tic-Orbit :proposal-id 17082 :visit-id "02" :orbit-number 3 :pcs-time 392 :si-vis-utilization 2260 :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 3025 :pcs-gap 0 ) (Tic-Orbit :proposal-id 17082 :visit-id "02" :orbit-number 4 :pcs-time 392 :si-vis-utilization 2260 :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 3025 :pcs-gap 0 ) (Tic-Orbit :proposal-id 17082 :visit-id "02" :orbit-number 5 :pcs-time 392 :si-vis-utilization 2260 :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 3025 :pcs-gap 0 ) (Tic-Orbit :proposal-id 17082 :visit-id "02" :orbit-number 6 :pcs-time 392 :si-vis-utilization 2260 :al-overhead-at-end 0 :internal-dur-at-end 727 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3025 :pcs-gap 0 ) true 6 0 The ETC says that the imaging exposure will modestly saturate, but a similar setting was used succesfully by GO 14793 on a comparably brightness star (HAT-11). It's okay to saturate the central pixel(s) because we are simply using this image to determine the position of the star on the array. Use same settings as GO 16307 (0.7"/s scan rate, 512 x 512 subarray). 1670030428933 The scheduling data was generated by CASM 30.3. CASM was run in Phase II mode. /private/var/folders/x9/xxl0qz1j6170fjlsyns6n4x80000gn/T/OPVisit13696863600273007564.xml All six orbits must be scheduled in a continuous block. Visit patterned after GO 16307 (PI Fu), which observed a secondary eclipse of this same target with G141. Overall efficiency is 51%, but this is needed in order to keep the maximum flux in an individual pixel < 33,000 electrons (recommendation from Wilkins et al. 2014 is fluxes below 30,000 electrons to avoid "hook" feature, but up to 40,000 seemed to work okay for HD 209458). Might consider if there are slightly slower scan rates/integration times that would result in a modestly higher peak electron flux but still stay below ~<35,000 electrons, but the gain in SNR is probably marginal and trades off against increased instrumental systematics. (Tic-Visit :proposal-id 17082 :visit-id "03" :proposal-version -1 :trans-version "20220630" :date "02-Dec-2022 20:18:08.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 6 :saa-model "30" :si-bright-earth-limb-angle 20.0 :data-volume 2713904 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 17082 :visit-id "03" :obset-id "03" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 17082 :visit-id "03" :orbit-number 1 :pcs-time 393 :si-vis-utilization 2232 :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 3025 :pcs-gap 0 ) (Tic-Orbit :proposal-id 17082 :visit-id "03" :orbit-number 2 :pcs-time 392 :si-vis-utilization 2260 :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 3025 :pcs-gap 0 ) (Tic-Orbit :proposal-id 17082 :visit-id "03" :orbit-number 3 :pcs-time 392 :si-vis-utilization 2260 :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 3025 :pcs-gap 0 ) (Tic-Orbit :proposal-id 17082 :visit-id "03" :orbit-number 4 :pcs-time 392 :si-vis-utilization 2260 :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 3025 :pcs-gap 0 ) (Tic-Orbit :proposal-id 17082 :visit-id "03" :orbit-number 5 :pcs-time 392 :si-vis-utilization 2260 :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 3025 :pcs-gap 0 ) (Tic-Orbit :proposal-id 17082 :visit-id "03" :orbit-number 6 :pcs-time 392 :si-vis-utilization 2260 :al-overhead-at-end 0 :internal-dur-at-end 727 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3025 :pcs-gap 0 ) true 6 0 The ETC says that the imaging exposure will saturate, but this same setting was used succesfully by GO 14793. It's okay to saturate the central pixel(s) because we are simply using this image to determine the position of the star on the array.