16464( 2) - 01-Dec-2020 13:12:35 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 16464 Version: 2 Check-in Time: 01-Dec-2020 13:12:35 STScI Edit Number: 0 Title Mapping the Porous Neutral Gas Reservoir in an Extremely High Ionization Galaxy ------------------------------------------------------------------------------------ Type Cycle GO 28 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. John Chisholm University of Texas at Austin Y CoI: Prof. Matthew James Hayes Stockholm University N CoI: Dr. Alaina L. Henry Space Telescope Science Institute N CoI: Prof. Daniel P. Stark University of Arizona N CoI: Dr. Jarle Brinchmann Universidade do Porto N CoI: Prof. Crystal Linn Martin University of California - Santa Barbara N CoI: Dr. Danielle Berg University of Texas at Austin N CoI: Prof. Dawn K. Erb University of Wisconsin - Milwaukee N CoI: Dr. Rongmon Bordoloi North Carolina State University N CoI: Dr. Bethan Lesley James Space Telescope Science Institute - ESA N CoI: Mr. Zuyi Chen University of Arizona N CoI: Dr. Alessandra Aloisi Space Telescope Science Institute N ------------------------------------------------------------------------------------ Abstract We do not empirically know how the first galaxies reionized the early universe. In particular, how does neutral gas transmit ionizing photons from gas-rich star-forming regions into the intergalactic medium? One solution is that small regions of ionized gas preferentially funnel ionizing photons out of galaxies. However, this anisotropic escape dramatically changes the morphology of cosmic reionization and the subsequent structure of the universe. The James Webb Space Telescope aims to provide the empirical foundation of the epoch of reionization, but it will not sufficiently resolve the morphology of neutral gas nor the isotropy of the escape of ionizing photons. Here, we propose 15 orbits of HST mid-cycle observations to obtain 35 pc spatial resolution WFC3 images of the neutral resonant Mg II emission line. The proposed high-ionization emission line galaxy has recently been discovered to have a massive, but porous, neutral gas reservoir. Regions of bright resonant Mg II emission will trace the low column density holes through which the newly observed Lyman Alpha must propagate through. These Mg II maps will test where photons are transmitted out of this galaxy to answer how isotropically ionizing photons stream into the intergalactic medium. We will complement the Mg II maps with optical emission line maps to determine whether strong optical lines trace these low column density holes. These observations are crucial for understanding upcoming JWST observations and will illuminate one of the key empirical obstacles towards understanding cosmic reionization. ------------------------------------------------------------------------------------ Observations Description ------------------------ Here we aim to image the Mg II emission from an extreme emission line galaxy with WFC3/UVIS. We then aim to understand why this resonant emission escapes the extreme emission line galaxy. To do this we will image the galaxy in 9 different filters: Mg II emission (F275W)m Mg II continuum (F280N), [O II] 16464( 2) - 01-Dec-2020 13:12:35 - [ 2] (F373N), [O II] continuum (F343N), [O III] (F502N), H-beta (F487N), the H-beta + [O III] continuum (F467N), H-alpha (F665N) and the H-alpha continuum (F645N). We use previous SDSS and MUSE spatially resolved imaging to determine the surface brightnesses that we must integrate down to and the WFC3/UVIS ETC to determine the required exposure times. We will break the individual visits up into 3 orbit visits. Where possible, we will try to have as long of visits as possible to increase the background and the CTE, while reducing the pre-flash required. We calculate the pre-flash required for each exposure using the WFC3 ETC and determining the flash required to reach a total background of 20 e-. We will use the WFC3 Dither-line pattern, which will allow us to do 2 exposures per filter set up to account for bad pixels and sub-sample the PSF. In order to avoid large buffer dump issues, we include some of our shorter orbits (e.g. H-alpha and O III) with some of our longer orbits. This enables the buffer dump to occur during the longer exposure. ------------------------------------------------------------------------------------ 16464( 2) - 01-Dec-2020 13:12:35 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 J1418+2102 GALAXY, EMISSION LINE RA=14H18M51.1190S, J2000 V = 17.74 NEBULA, STARBURST DEC=+21D02'39.84" Reference Frame: ICRS Extended: YES ------------------------------------------------------------------------------------------------------------------------------------ 16464( 2) - 01-Dec-2020 13:12:35 - [ 4] Patterns ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 1 Primary_Pattern Secondary_Pattern Pattern_Type WFC3-UVIS-DITHER-LINE Pattern_Purpose DITHER Number_Of_Points 2 Point_Spacing 0.145 Line_Spacing Coordinate_Frame POS-TARG Pattern_Orient 46.84 Angle_Between_Sides Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ 16464( 2) - 01-Dec-2020 13:12:35 - [ 5] Visit: 01 (Mg II + H-alpha) 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 J1418+2102 WFC3/UVI ACCUM UVIS2 F275W FLASH=6 1 2700 S PATTERN 1 1 S see below (5523 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 J1418+2102 WFC3/UVI ACCUM UVIS2 F665N FLASH=14 1 135 S PATTERN 1 2-3 S see below (270 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 J1418+2102 WFC3/UVI ACCUM UVIS2 F275W FLASH=11 1 1500 S S see below (2012 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 | ------------------------------------------------------------------------------------------------------------------------------------ J1418+2102 1 WFC3/UVI ACCUM UVIS2 F275W 1 none none none 1 2766.0 S S J1418+2102 1 WFC3/UVI ACCUM UVIS2 F275W 2 none none none 2 2757.0 S S J1418+2102 2 WFC3/UVI ACCUM UVIS2 F665N 1 none none none 3 135.0 S S J1418+2102 2 WFC3/UVI ACCUM UVIS2 F665N 2 none none none 3 135.0 S S J1418+2102 3 WFC3/UVI ACCUM UVIS2 F275W 1 none none none 3 1006.0 S S J1418+2102 3 WFC3/UVI ACCUM UVIS2 F275W 2 none none none 3 1006.0 S S 16464( 2) - 01-Dec-2020 13:12:35 - [ 6] Visit: 02 (Mg II + O III) 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 J1418+2102 WFC3/UVI ACCUM UVIS2 F275W FLASH=6 1 2700 S PATTERN 1 1 S see below (5523 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 J1418+2102 WFC3/UVI ACCUM UVIS2 F502N FLASH=12 1 135 S PATTERN 1 2-3 S see below (270 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 J1418+2102 WFC3/UVI ACCUM UVIS2 F275W FLASH=11 1 1500 S S see below (2004 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 | ------------------------------------------------------------------------------------------------------------------------------------ J1418+2102 1 WFC3/UVI ACCUM UVIS2 F275W 1 none none none 1 2766.0 S S J1418+2102 1 WFC3/UVI ACCUM UVIS2 F275W 2 none none none 2 2757.0 S S J1418+2102 2 WFC3/UVI ACCUM UVIS2 F502N 1 none none none 3 135 S S J1418+2102 2 WFC3/UVI ACCUM UVIS2 F502N 2 none none none 3 135 S S J1418+2102 3 WFC3/UVI ACCUM UVIS2 F275W 1 none none none 3 1002.0 S S J1418+2102 3 WFC3/UVI ACCUM UVIS2 F275W 2 none none none 3 1002.0 S S 16464( 2) - 01-Dec-2020 13:12:35 - [ 7] Visit: 03 (Mg II + H-alpha continuum) 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 J1418+2102 WFC3/UVI ACCUM UVIS2 F275W FLASH=6 1 2700 S PATTERN 1 1 S see below (5523 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 J1418+2102 WFC3/UVI ACCUM UVIS2 F645N FLASH=12 1 270 S PATTERN 1 2-3 S see below (518 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 J1418+2102 WFC3/UVI ACCUM UVIS2 F275W FLASH=11 1 1500 S S see below (1756 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 | ------------------------------------------------------------------------------------------------------------------------------------ J1418+2102 1 WFC3/UVI ACCUM UVIS2 F275W 1 none none none 1 2766.0 S S J1418+2102 1 WFC3/UVI ACCUM UVIS2 F275W 2 none none none 2 2757.0 S S J1418+2102 2 WFC3/UVI ACCUM UVIS2 F645N 1 none none none 3 259.0 S S J1418+2102 2 WFC3/UVI ACCUM UVIS2 F645N 2 none none none 3 259.0 S S J1418+2102 3 WFC3/UVI ACCUM UVIS2 F275W 1 none none none 3 878.0 S S J1418+2102 3 WFC3/UVI ACCUM UVIS2 F275W 2 none none none 3 878.0 S S 16464( 2) - 01-Dec-2020 13:12:35 - [ 8] Visit: 04 (Mg II Continuum) 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 J1418+2102 WFC3/UVI ACCUM UVIS2 F280N FLASH=10 1 2700 S PATTERN 1 1 S see below (5523 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 J1418+2102 WFC3/UVI ACCUM UVIS2 F280N FLASH=13 1 1311 S PATTERN 1 2 S see below (2621 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 | ------------------------------------------------------------------------------------------------------------------------------------ J1418+2102 1 WFC3/UVI ACCUM UVIS2 F280N 1 none none none 1 2766.0 S S J1418+2102 1 WFC3/UVI ACCUM UVIS2 F280N 2 none none none 2 2757.0 S S J1418+2102 2 WFC3/UVI ACCUM UVIS2 F280N 1 none none none 3 1310.0 S S J1418+2102 2 WFC3/UVI ACCUM UVIS2 F280N 2 none none none 3 1311.0 S S 16464( 2) - 01-Dec-2020 13:12:35 - [ 9] Visit: 05 (Emission Lines) 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 J1418+2102 WFC3/UVI ACCUM UVIS2 F467M FLASH=12 1 259 S (518 PATTERN 1 1-2 S S) ------------------------------------------------------------------------------------------------------------------------------------ 2 J1418+2102 WFC3/UVI ACCUM UVIS2 F275W FLASH=12 1 874 S S see below (1807 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 J1418+2102 WFC3/UVI ACCUM UVIS2 F343N FLASH=12 1 270 S PATTERN 1 3-4 S see below (858 S) ------------------------------------------------------------------------------------------------------------------------------------ 4 J1418+2102 WFC3/UVI ACCUM UVIS2 F487N FLASH=10 1 650 S S see below (1418 S) ------------------------------------------------------------------------------------------------------------------------------------ 5 J1418+2102 WFC3/UVI ACCUM UVIS2 F373N FLASH=12 1 1311 S PATTERN 1 5 S (2622 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 | ------------------------------------------------------------------------------------------------------------------------------------ J1418+2102 1 WFC3/UVI ACCUM UVIS2 F467M 1 none none none 1 N/A S J1418+2102 1 WFC3/UVI ACCUM UVIS2 F467M 2 none none none 1 N/A S J1418+2102 2 WFC3/UVI ACCUM UVIS2 F275W 1 none none none 1 933.0 S S J1418+2102 2 WFC3/UVI ACCUM UVIS2 F275W 2 none none none 1 N/A S J1418+2102 3 WFC3/UVI ACCUM UVIS2 F343N 1 none none none 2 429.0 S S J1418+2102 3 WFC3/UVI ACCUM UVIS2 F343N 2 none none none 2 429.0 S S J1418+2102 4 WFC3/UVI ACCUM UVIS2 F487N 1 none none none 2 709.0 S S J1418+2102 4 WFC3/UVI ACCUM UVIS2 F487N 2 none none none 2 709.0 S S J1418+2102 5 WFC3/UVI ACCUM UVIS2 F373N 1 none none none 3 N/A S 16464( 2) - 01-Dec-2020 13:12:35 - [ 10] 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 | ------------------------------------------------------------------------------------------------------------------------------------ J1418+2102 5 WFC3/UVI ACCUM UVIS2 F373N 2 none none none 3 N/A S 16464( 2) - 01-Dec-2020 13:12:35 - [ 11] Summary Form for Proposal 16464 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures UVIS2 ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFC3/UVIS ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters FLASH=10, FLASH=11, FLASH=12, FLASH=13, FLASH=14, FLASH=6 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements PATTERN 1 1, PATTERN 1 1-2, PATTERN 1 2, PATTERN 1 2-3, PATTERN 1 3-4, PATTERN 1 5 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F275W, F280N, F343N, F373N, F467M, F487N, F502N, F645N, F665N ------------------------------------------------------------------------------------------------------------------------------------ Target Names J1418+2102 ------------------------------------------------------------------------------------------------------------------------------------