Given the rapidly evolving nature of the object we hope this DD proposal can be reviewed quickly -1941106331 Assigned ID: 5909 ----- Attempting Submission 1 (Fri Apr 12 09:32:51 GMT 2024) ----- HST Phase I Proposal 5909 successfully submitted. Receipt: # 5909-1 ----- Attempting Submission 2 (Fri Apr 12 09:38:41 GMT 2024) ----- The number of orbits used exceeds the number allocated ORBITAL VISIBILITY OVERRUN Creating new Visit 4 to replace Visits 1 and 3 in response to failed visit due to gyro issues and then reduced gyro mode operations. Note the addition of the FUV was approved by the TTRB and will require a new BOP review 1759408461 ----- Attempting Submission 1 (Fri Apr 19 19:28:30 GMT 2024) ----- ----- Attempting Submission 2 (Mon Apr 22 18:52:04 GMT 2024) ----- ----- Attempting Submission 3 (Sun May 12 17:20:51 GMT 2024) ----- ----- Attempting Submission 4 (Tue Aug 13 22:30:04 GMT 2024) ----- its been run on the modified visits Exploring the Ultraviolet Evolution of SN 2024ggi: Unveiling Red Supergiant Mass Loss with HST Spectroscopy Hydrogen-rich supernovae, the end phase of massive star evolution, offer critical insights into stellar evolution and the interplay between stars and their surroundings. SN 2024ggi exploded on Apr 10, 2024 in NGC 3621(D=6.5-7.5 Mpc). This nearby event presents a rare opportunity to investigate the interaction between the SN ejecta and circumstellar material in unprecedented detail. Leveraging the unique ultraviolet capabilities of the Hubble Space Telescope (HST), we propose to map the mass loss history of the progenitor star over the its last 25 years by observing the supernova at 10, 20, 50 and 100 days post-explosion. With these observations, we can not only trace the evolution of circumstellar interaction, but also study the elemental composition of the circumstellar material and shed light on the mechanisms driving mass loss in massive stars. By comparing our observations with the extensively studied hydrogen-rich SN 2023ixf, we will determine commonalities and differences in their mass loss processes and their impact on supernova evolution. Beyond fundamental questions in stellar astrophysics this proposal also lays the groundwork for interpreting high-redshift hydrogen-rich supernovae. Additionally, this proposal fills a critical gap in our understanding of of the evolution of hydrogen-rich supernovae as there are only a handful of core-collapse supernovae with HST ultraviolet observations and the majority of them occur within 3 weeks of explosion. Probing the late phases of ultraviolet evolution, after the flux has normally faded can only be done for a supernova this nearby and only with HST. This is a disruptive ToO to monitor the evolution CSM interaction with the ejecta of SN 2024ggi. We request observations at 20, 50, and 100d. Day 20 will be with the STIS/CCD detector to allow rapid schedulability without the need for a BOP review and day 50 and 100 will be with the STIS/NUV detector. We allow the first visit to execute between 15-25d The second and third visit have a +/-10 d window around our preferred epoch K. A. Bostroem extensive experience with the STIS data reduction and the reduction and analysis of core collapse supernovae observations with HST, Swift, and Gemini. Her research focuses on understanding the progenitors of hydrogen-rich CC SNe. M. Lundquist is an active member of the DLT40 team and specializes in the reduction and analysis of Gemini and Keck. He is currently a staff astronomer at the W. M. Keck Observatory. Prior to joining the DLT40 team, he worked as a Gemini Science Fellow at the Gemini Observatories. S. Valenti is the co-PI of DLT40. He has worked comprehensively on core collapse supernovae (CC SNe). D. Sand is the co-PI of the DLT40 survey and an expert in the progenitors of Type Ia SNe and SN environments. He has extensive experience with Swift, and Gemini observations of SNe and their environments. J. Andrews is an active member of the DLT40 team, has expertise observing with HST/STIS, and is an assistent astronomer the Gemini Observatory. Her research focuses on characterizing the progenitors of core collapse (CC) SNe, specifically focusing on their mass-loss history via circumstellar interaction. G. Hosseinzadeh is an expert in early interaction in CCSNe and has experience analyzing early UV data. He leads the US team's contribution to the Global Supernova Project, which is already collecting a high candence ground based observing campaign with the Las Cumbres Observatory. M. Shrestha is a Postdoctoral Research Associate at the University of Arizona. Her research focuses on the transients such as long gamma-ray bursts, core collapse (CC) SNe, and kilonova. She is part of DLT40 and SAGUARO collaboration. J. Pearson is focusing her thesis research on understanding the progenitors and environments of CC SNe and is an active member of the DLT40 team. Y. Dong is an active member of the DLT40 team and has experience analyzing both CC~SNe and SN~I. N. Meza and Emily Hoang are the newest member of the DLT40 team focusing their theses work on CC~SNe. A. Ravi: Aravind P. Ravi has experience working with multi-wavelength spectroscopy of core-collapse supernovae through his work on Type Ic SN 2021krf where the team identified a luminous late-time emission from a central engine and an early onset of dust formation. Stellar Physics and Stellar Types 0 false SUPPORTED EXT-STAR SUPERNOVA SUPERNOVA TYPE II J2000 J2000 STIS/CCD Spectroscopic No No G230LB 2375 STIS/CCD Spectroscopic No No G430L 4300 STIS/CCD Spectroscopic No No G230LB 2375 STIS/CCD Spectroscopic No No G430L 4300 STIS/CCD Spectroscopic No No G230LB 2375 STIS/NUV-MAMA Spectroscopic No No G230L 2376 The scheduling data was generated by CASM 32.0. CASM was run in Phase II mode. /private/var/folders/6l/54htg8p52b762n_6mhsb13v80000gn/T/OPVisit11855067412339301920.xml WITHDRAW THIS VISIT - REPLACED WITH VISIT 4 (Tic-Visit :proposal-id 17614 :visit-id "01" :proposal-version -1 :trans-version "20240604" :date "13-Aug-2024 11:11:48.0" :trans-errors '(:WARNINGS 1 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 1 :saa-model "24" :si-bright-earth-limb-angle 20.0 :data-volume 147648 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 17614 :visit-id "01" :obset-id "01" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 17614 :visit-id "01" :orbit-number 1 :pcs-time 380 :si-vis-utilization 2716 :al-overhead-at-end 0 :internal-dur-at-end 379 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3034 :pcs-gap 0 ) true 1 1 STIS DD 23ixf visit 2 spectrum renormalized to V=12.35 w/ E(B-V)=0.3 STIS DD 23ixf visit 2 spectrum renormalized to V=12.35 w/ E(B-V)=0.3 STIS DD 23ixf visit 2 spectrum renormalized to V=12.35 w/ E(B-V)=0.3 The scheduling data was generated by CASM 32.0. CASM was run in Phase II mode. 1716357953000 100.60000000000002 (Tic-Visit :proposal-id 17614 :visit-id "02" :proposal-version -1 :trans-version "20231220" :date "22-Apr-2024 11:49:43.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 2 :saa-model "24" :si-bright-earth-limb-angle 20.0 :data-volume 174416 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 17614 :visit-id "02" :obset-id "02" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 17614 :visit-id "02" :orbit-number 1 :pcs-time 443 :si-vis-utilization 2716 :al-overhead-at-end 0 :internal-dur-at-end 113 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3159 :pcs-gap 0 ) (Tic-Orbit :proposal-id 17614 :visit-id "02" :orbit-number 2 :pcs-time 392 :si-vis-utilization 2767 :al-overhead-at-end 85 :internal-dur-at-end 394 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3159 :pcs-gap 0 ) true 2 0 STIS DD 23ixf visit 5 spectrum renormalized to V=12.9 w/ E(B-V)=0.3 STIS DD 23ixf visit 5 spectrum renormalized to V=12.9 w/ E(B-V)=0.3 STIS DD 23ixf visit 5 spectrum renormalized to V=12.9 w/ E(B-V)=0.3 The scheduling data was generated by CASM 32.0. CASM was run in Phase II mode. WITHDRAW THIS VISIT - REPLACED WITH VISIT 4 (Tic-Visit :proposal-id 17614 :visit-id "03" :proposal-version -1 :trans-version "20231220" :date "22-Apr-2024 11:48:16.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 3 :saa-model "24" :si-bright-earth-limb-angle 20.0 :data-volume 261408 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 17614 :visit-id "03" :obset-id "03" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 17614 :visit-id "03" :orbit-number 1 :pcs-time 443 :si-vis-utilization 2716 :al-overhead-at-end 0 :internal-dur-at-end 113 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3159 :pcs-gap 0 ) (Tic-Orbit :proposal-id 17614 :visit-id "03" :orbit-number 2 :pcs-time 392 :si-vis-utilization 2767 :al-overhead-at-end 85 :internal-dur-at-end 132 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3159 :pcs-gap 0 ) (Tic-Orbit :proposal-id 17614 :visit-id "03" :orbit-number 3 :pcs-time 392 :si-vis-utilization 2767 :al-overhead-at-end 85 :internal-dur-at-end 394 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3159 :pcs-gap 0 ) true 3 0 FLOYDS 23ixf 8/26 (day 100) spectrum renormalized to V=15.6 w/ E(B-V)=0.3 STIS DD 23ixf visit 2 spectrum renormalized to V=15.6 w/ E(B-V)=0.3 STIS DD 23ixf visit 2 spectrum renormalized to V=15.6 w/ E(B-V)=0.3 STIS DD 23ixf visit 2 spectrum renormalized to V=15.6 w/ E(B-V)=0.3 /private/var/folders/6l/54htg8p52b762n_6mhsb13v80000gn/T/OPVisit13945217838696115742.xml The scheduling data was generated by CASM 32.1.1. CASM was run in Phase II mode. Estimated brightness V=17.5 is from SN 2018zd V band light curve (with 24ggi distance and extinction) at 225d based on match to the light curve. SN 2018zd had a large fall from plateau so we consider this a conservative estimate Inclusion of FUV approved by TTRB - but this will need a new BOP check (Tic-Visit :proposal-id 17614 :visit-id "04" :proposal-version -1 :trans-version "20240604" :date "13-Aug-2024 15:28:50.0" :trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0 :FATAL-ERRORS 0 :CONTINUABLE-FATALS 0) :number-of-orbits 4 :saa-model "24" :si-bright-earth-limb-angle 20.0 :data-volume 365856 :tdrss-contact-duration 0 :coron NIL ) (Tic-Obset :proposal-id 17614 :visit-id "04" :obset-id "04" :pcs-mode "FGS" ) (Tic-Orbit :proposal-id 17614 :visit-id "04" :orbit-number 1 :pcs-time 380 :si-vis-utilization 2651 :al-overhead-at-end 0 :internal-dur-at-end 113 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3034 :pcs-gap 0 ) (Tic-Orbit :proposal-id 17614 :visit-id "04" :orbit-number 2 :pcs-time 380 :si-vis-utilization 2653 :al-overhead-at-end 85 :internal-dur-at-end 132 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3034 :pcs-gap 0 ) (Tic-Orbit :proposal-id 17614 :visit-id "04" :orbit-number 3 :pcs-time 380 :si-vis-utilization 2653 :al-overhead-at-end 198 :internal-dur-at-end 0 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3034 :pcs-gap 0 ) (Tic-Orbit :proposal-id 17614 :visit-id "04" :orbit-number 4 :pcs-time 380 :si-vis-utilization 2653 :al-overhead-at-end 198 :internal-dur-at-end 319 :dark-offset NIL :dark-utilization 0 :max-dark-utilization 1920 :low-sky "N" :pcs-visibility 3034 :pcs-gap 0 ) true 4 0