15161( 3) - 12-Dec-2018 18:02:19 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 15161 Version: 3 Check-in Time: 12-Dec-2018 18:02:19 STScI Edit Number: 0 Title The fate of infalling gas during its final approach onto the Milky Way disk ------------------------------------------------------------------------------------ Type Cycle GO 25 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. Kat A Barger Texas Christian University Y CoI: Dr. Andrew J. Fox Space Telescope Science Institute - ESA N CoI: Dr. Felix J. Lockman Associated Universities, Inc. N CoI: Dr. Lauren Corlies LSST N CoI: Dr. Molly Peeples Space Telescope Science Institute N CoI: Dr. Alex S Hill University of British Columbia N ------------------------------------------------------------------------------------ Abstract The Smith high-velocity cloud is an advanced stage of falling onto the Milky Way's disk. Its compressed head, comatary morphology structure, and diffuse tail---as well as the adjacent cloud fragments along its length---all indicate that this cloud is interacting strongly with its environment. The Smith Cloud has been studied extensively, making it an ideal candidate to assess the mechanisms that disrupt gas as it is deposited onto an Lstar galaxy and to assess how efficiently this S/H = 0.5 solar metallicity cloud disperses metals into the surrounding coronal gas. We will explore the properties of a cloud that recently splintered off the main body of the Smith Cloud using new HST/COS/G130M observations toward 2 QSOs. We will compare this freshly stripped cloud fragment with the gas in the wake of the Smith Cloud, which is in an advanced state of mixing, using published HST/COS/G130M observations toward 3 QSOs. We will combine these observations with already acquired spectroscopically resolved HI 21-cm (0.03 kpc resolution) and H-alpha (0.2 kpc resolution) emission maps to investigate how efficiently the surrounding coronal gas and ionizing radiation field are disturbing this cloud. Using spatial maps of the ionization conditions, chemical composition, and gas motions of a high-velocity cloud, we will further develop a model which uses hydrodynamical simulations with metal mixing and gas condensation to describe the evaporation timescale of galactic fountains as they flow onto Lstar galaxies. ------------------------------------------------------------------------------------ Observations Description ------------------------ This is a 7-orbit proposal to observe two background QSO targets in the direction of the Smith Cloud. V01 observes a QSO (GALAX-J204402.0-075809, z=0.1034) using the COS G130M grating with central wavelength set to 1291 AA for 3 orbits. It uses an ACQ/IMAGE with MIRRORB. We will also use the 2 FP-POS positions to dither the placing of the spectrum on the grating. V02 observes a QSO (GALAX-J20333589-0320385, z=0.6964) using the COS G130M grating with central wavelength set to 1291 AA for the 4 orbits. It uses an ACQ/IMAGE with MIRRORB. We will also use the 2 FP-POS positions to dither the 15161( 3) - 12-Dec-2018 18:02:19 - [ 2] placing of the spectrum on the grating. ------------------------------------------------------------------------------------ 15161( 3) - 12-Dec-2018 18:02:19 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 GALEX-J20440 ISM, ABSORPTION LINE RA=20H44M2.0274S +/- 0.2", J2000 Z = V = 17.31 GALEX FUV MAG = 17.78, 2.0-075809 SYSTEM - GALACTIC, HIGH DEC=-07D58'9.44" +/- 0.2" 0.1034 Magnitude give in B (V MAG unavailible) VELOCITY CLOUD Reference Frame: ICRS Extended: NO Comments: This object was generated by the targetselector and retrieved from the GALEX database. ------------------------------------------------------------------------------------------------------------------------------------ 2 GALEX-J20333 ISM, ABSORPTION LINE RA=20H33M35.8773S +/- 0.2", J2000 Z = V = 17.73952 GALEX FUV MAG = 17.74 NUV 5.8-032038 SYSTEM - GALACTIC, HIGH DEC=-03D20'38.65" +/- 0.2" 0.6964 MAG=17.07 VELOCITY CLOUD Reference Frame: ICRS Extended: NO Comments: This object was generated by the targetselector and retrieved from the GALEX database. ------------------------------------------------------------------------------------------------------------------------------------ 15161( 3) - 12-Dec-2018 18:02:19 - [ 4] Visit: 01 (J20440203-0758105) Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 GALEX-J2044 COS/NUV ACQ/SEA PSA MIRRORB SCAN-SIZE=2, STEP-SIZE=1.767, 1 30 S (30 02.0-075809 RCH CENTER=FLUX-WT S) ------------------------------------------------------------------------------------------------------------------------------------ 2 GALEX-J2044 COS/NUV ACQ/IMA PSA MIRRORB 1 44 S (44 02.0-075809 GE S) ------------------------------------------------------------------------------------------------------------------------------------ 3 GALEX-J2044 COS/FUV TIME-TA PSA G130M 1291 BUFFER-TIME=3473, FP-POS=3 1 2097 S 02.0-075809 G (2097 S) ------------------------------------------------------------------------------------------------------------------------------------ 4 GALEX-J2044 COS/FUV TIME-TA PSA G130M 1291 FP-POS=4, BUFFER-TIME=3473 1 2779 S 02.0-075809 G (2779 S) ------------------------------------------------------------------------------------------------------------------------------------ 5 GALEX-J2044 COS/FUV TIME-TA PSA G130M 1291 FP-POS=3, BUFFER-TIME=3473 1 2779 S 02.0-075809 G (2779 S) ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ GALEX-J204402.0-075 1 COS/NUV ACQ/SEA PSA MIRRORB none none none none 1 N/A 809 RCH GALEX-J204402.0-075 2 COS/NUV ACQ/IMA PSA MIRRORB none none none none 1 N/A 809 GE GALEX-J204402.0-075 3 COS/FUV TIME-TA PSA G130M 1291 none none none none 1 N/A 809 G GALEX-J204402.0-075 4 COS/FUV TIME-TA PSA G130M 1291 none none none none 2 N/A 809 G GALEX-J204402.0-075 5 COS/FUV TIME-TA PSA G130M 1291 none none none none 3 N/A 809 G 15161( 3) - 12-Dec-2018 18:02:19 - [ 5] Visit: 02 (J20333589-0320285) Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exp | Target | Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Num | Name | Config | Mode | or FOV |Element |Waveln.| Parameters |Exp| (Total) | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 GALEX-J2033 COS/NUV ACQ/SEA PSA MIRRORB SCAN-SIZE=2, STEP-SIZE=1.767, 1 40 S (40 35.8-032038 RCH CENTER=FLUX-WT S) ------------------------------------------------------------------------------------------------------------------------------------ 2 GALEX-J2033 COS/NUV ACQ/IMA PSA MIRRORB 1 51 S (51 35.8-032038 GE S) ------------------------------------------------------------------------------------------------------------------------------------ 3 GALEX-J2033 COS/FUV TIME-TA PSA G130M 1291 FP-POS=3, BUFFER-TIME=4048 1 2040 S 35.8-032038 G (2040 S) ------------------------------------------------------------------------------------------------------------------------------------ 4 GALEX-J2033 COS/FUV TIME-TA PSA G130M 1291 FP-POS=4, BUFFER-TIME=4048 1 2776 S 35.8-032038 G (2776 S) ------------------------------------------------------------------------------------------------------------------------------------ 5 GALEX-J2033 COS/FUV TIME-TA PSA G130M 1291 FP-POS=3, BUFFER-TIME=4048 1 2776 S 35.8-032038 G (2776 S) ------------------------------------------------------------------------------------------------------------------------------------ 6 GALEX-J2033 COS/FUV TIME-TA PSA G130M 1291 FP-POS=4, BUFFER-TIME=4048 1 2776 S 35.8-032038 G (2776 S) ------------------------------------------------------------------------------------------------------------------------------------ Sub Exposures ------------------------------------------------------------------------------------------------------------------------------------ Target | Exp |Instr | Oper. | Aper |Spectral|Cent.|Primary |Secondary |Iteration |CR-SPLIT |Orbit |Duration Name | Num |Config | Mode | or FOV |Element |Wave.|Pattern Pos |Pattern Pos |Num |Num |Number | ------------------------------------------------------------------------------------------------------------------------------------ GALEX-J203335.8-032 1 COS/NUV ACQ/SEA PSA MIRRORB none none none none 1 N/A 038 RCH GALEX-J203335.8-032 2 COS/NUV ACQ/IMA PSA MIRRORB none none none none 1 N/A 038 GE GALEX-J203335.8-032 3 COS/FUV TIME-TA PSA G130M 1291 none none none none 1 N/A 038 G GALEX-J203335.8-032 4 COS/FUV TIME-TA PSA G130M 1291 none none none none 2 N/A 038 G GALEX-J203335.8-032 5 COS/FUV TIME-TA PSA G130M 1291 none none none none 3 N/A 038 G GALEX-J203335.8-032 6 COS/FUV TIME-TA PSA G130M 1291 none none none none 4 N/A 038 G 15161( 3) - 12-Dec-2018 18:02:19 - [ 6] Summary Form for Proposal 15161 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures PSA ------------------------------------------------------------------------------------------------------------------------------------ Configurations COS/FUV, COS/NUV ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACQ/IMAGE, ACQ/SEARCH, TIME-TAG ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters BUFFER-TIME=3473, BUFFER-TIME=4048, CENTER=FLUX-WT, FP-POS=3, FP-POS=4, SCAN-SIZE=2, STEP-SIZE=1.767 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements G130M, MIRRORB ------------------------------------------------------------------------------------------------------------------------------------ Target Names GALEX-J203335.8-032038, GALEX-J204402.0-075809 ------------------------------------------------------------------------------------------------------------------------------------