13639( 6) - 28-Aug-2015 16:07:31 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 13639 Version: 6 Check-in Time: 28-Aug-2015 16:07:31 STScI Edit Number: 2 Title Resolving Lyman-alpha Emission On Physical Scales < 270 pc at z > 4 ------------------------------------------------------------------------------------ Type Cycle GO 22 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. Matthew Bayliss Colby College Y CoI: Dr. Takatoshi Shibuya University of Tokyo, Institute of Cosmic N Ray Research CoI: Prof. Keren Sharon University of Michigan N CoI: Dr. Grant R. Tremblay Yale University N CoI: Prof. Michael D. Gladders University of Chicago N CoI: Dr. Eva Wuyts Max-Planck-Institut fur extraterrestrische N Physik CoI: Dr. Jane R. Rigby NASA Goddard Space Flight Center N CoI: Prof. Nobunari Kashikawa National Astronomical Observatory of Japan N (NAOJ) CoI: Ms. Traci Lin Johnson University of Michigan N CoI: Mr. Michael Florian University of Chicago N CoI: Dr. Haakon Dahle University of Oslo N CoI: Prof. Christopher W. Stubbs Harvard University N ------------------------------------------------------------------------------------ Abstract We propose ACS-WFC Ramp narrowband imaging of six strongly lensed Lyman-alpha Emitters (LAEs) at z > 4 that will spatially resolve the Lyman-alpha line emitting regions on scales < 270 pc. The best available observations (HST, Spitzer, 10m ground based telescopes) are unable to provide robust measurements of the structure of these galaxies from blank field studies, but strong gravitational lensing provides a unique opportunity to peer into the heart of young star forming galaxies at high redshift and address outstanding questions regarding their morphology and evolution. Strong lensing magnifies each of our target LAEs, increasing the effective spatial resolution of ACS-WFC such that the point spread function will correspond to physical scales < 270 parsecs within all six z > 4 galaxies. Additionally, the boost in flux due to gravitational lensing makes our proposed targets the brightest sources of their kind at these redshifts, in spite of the fact that they are intrinsically ~L* LAEs. The proposed observations will probe the morphological properties of Lyman-alpha and UV continuum emission in typical/representative high-redshift LAEs with signal-to-noise and spatial resolution comparable to studies of Lyman-alpha emitting galaxies in the z ~ 0.1 universe. The resulting data will bridge the gap between deep ground-based studies of blank field LAEs at high redshift, and detailed studies of low-redshift LAEs. ------------------------------------------------------------------------------------ Observations Description ------------------------ We will be acquiring ACS-WFC Ramp Filter observations of six strongly lensed Lyman Alpha Emitters (LAEs). One of the six targets will also require broadband F850LP observations. Each target will be observed for either 2 or 3 orbits. The 13639( 6) - 28-Aug-2015 16:07:31 - [ 2] three targets with 2 orbits will have 4 individual exposures in each filter (this includes the one target that will have both Ramp Filter and broadband observations). The three targets with 3 orbits will have 6 individual Ramp Filter exposures (2/orbit). From these data we will measure the spatial extent and morphology of Lyan-alpha and rest-frame UV emission emitting regions on physical scales of <270 pc, where the high spatial resolution is achieved via the combination of superb HST image quality and magnification from gravitational lensing. We optimize ramp filter wavelength settings to match the Lyman-alpha line emission for each target. From the available imaging and spectroscopy we generate precise estimates of the integration times necessary to achieve good S/N in the ramp narrowband imaging for each source. We calculate the necessary integration times to achieve a minimum S/N of $\gtrsim$30 per LAE using the ACS/Ramp and ACS/imaging exposure time calculator (ETC). The choice of minimum S/N ensures that we can measure a robust radial light profile for these sources regardless of whether they are highly compact, or extended in Lyman-alpha. The orbit packing for these observations is straightforward, and for all targets we will employ a dither pattern with a minimum of four individual exposures per source, per filter in order to facilitate cosmic ray rejection. The dithering uses dither steps intended to subsample the pixel array to improve the quality of the final PSF reconstruction, post drizzling, and to help mitigate the impact of any chip defects. Due to the low background (between ~8-20 e- per pixel for our various exposures) expected in our data, we also apply a post-flash to each exposure in order to facilitate charge transfer efficiency (CTE) corrections. ------------------------------------------------------------------------------------ 13639( 6) - 28-Aug-2015 16:07:31 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 SGASJ091541+ GALAXY, GRAVITATIONAL RA=09H15M41.0300S +/- 0.2", J2000 V = 24.0 +/- 1.0 i = 22.8, z = 23.3 382655 LENS, HIGH REDSHIFT DEC=+38D26'53.50" +/- 0.2" GALAXY, LYMAN ALPHA CLOUD, STAR FORMING REGION Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 2 SGASJ115201+ GALAXY, GRAVITATIONAL RA=11H52M0.9260S +/- 0.2", J2000 V = 24.0 +/- 1.0 r = 23.5, i = 24.2 331347 LENS, HIGH REDSHIFT DEC=+33D13'43.32" +/- 0.2" GALAXY, LYMAN ALPHA CLOUD, STAR FORMING REGION Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 3 SGASJ134331+ GALAXY, GRAVITATIONAL RA=13H43M30.6680S +/- 0.2", J2000 V = 24.0 +/- 1.0 i = 23.3, z=23.3 415455 LENS, HIGH REDSHIFT DEC=+41D54'55.00" +/- 0.2" GALAXY, LYMAN ALPHA CLOUD, STAR FORMING REGION Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 4 SGASJ162132+ GALAXY, GRAVITATIONAL RA=16H21M32.8460S +/- 0.2", J2000 V = 22.7 +/- 0.2 r = 22.2, i = 22.3 060705 LENS, HIGH REDSHIFT DEC=+06D07'7.97" +/- 0.2" GALAXY, LYMAN ALPHA CLOUD, STAR FORMING REGION Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 5 RCS1J022431- GALAXY, GRAVITATIONAL RA=02H24M33.5430S +/- 0.2", J2000 V = 24.22 +/- 0.24 F814W = 22.1, 0002.5C LENS, HIGH REDSHIFT DEC=-00D02'21.77" +/- 0.2" Rc=22.4 GALAXY, LYMAN ALPHA CLOUD, STAR FORMING REGION Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 6 SGASJ105038+ GALAXY, GRAVITATIONAL RA=10H50M38.6000S +/- 0.2", J2000 V = 24.4 +/- 0.5 i =22.7 001715 LENS, HIGH REDSHIFT DEC=+00D17'11.38" +/- 0.2" GALAXY, LYMAN ALPHA CLOUD, STAR FORMING REGION Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 13639( 6) - 28-Aug-2015 16:07:31 - [ 4] Patterns ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 5 Primary_Pattern Secondary_Pattern Pattern_Type ACS-WFC-DITHER-BOX Pattern_Purpose DITHER Number_Of_Points 4 Point_Spacing 0.265 Line_Spacing 0.187 Coordinate_Frame POS-TARG Pattern_Orient 20.67 Angle_Between_Sides 69.05 Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 6 Primary_Pattern Secondary_Pattern Pattern_Type ACS-WFC-DITHER-LINE Pattern_Purpose DITHER Number_Of_Points 2 Point_Spacing 3.011 Line_Spacing Coordinate_Frame POS-TARG Pattern_Orient 85.28 Angle_Between_Sides Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 7 Primary_Pattern Secondary_Pattern Pattern_Type ACS-WFC-DITHER-LINE Pattern_Purpose DITHER Number_Of_Points 2 Point_Spacing 0.187 Line_Spacing Coordinate_Frame POS-TARG Pattern_Orient 175.28 Angle_Between_Sides Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ 13639( 6) - 28-Aug-2015 16:07:31 - [ 5] Visit: 01 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 SGASJ091541 ACS/WFC ACCUM WFC2-ORAM FR782N 7510 FLASH=25 1 1300 S PATTERN 5 1 +382655 P see below (5302 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 SGASJ091541 ACS/WFC ACCUM WFC2-ORAM FR782N 7510 FLASH=25 1 1300 S PATTERN 6 2 +382655 P see below (2744 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 | ------------------------------------------------------------------------------------------------------------------------------------ SGASJ091541+382655 1 ACS/WFC ACCUM WFC2-ORA FR782N 7510 1 none none none 1 1277.0 S MP SGASJ091541+382655 1 ACS/WFC ACCUM WFC2-ORA FR782N 7510 2 none none none 1 1277.0 S MP SGASJ091541+382655 1 ACS/WFC ACCUM WFC2-ORA FR782N 7510 3 none none none 2 1374.0 S MP SGASJ091541+382655 1 ACS/WFC ACCUM WFC2-ORA FR782N 7510 4 none none none 2 1374.0 S MP SGASJ091541+382655 2 ACS/WFC ACCUM WFC2-ORA FR782N 7510 1 none none none 3 1383.0 S MP SGASJ091541+382655 2 ACS/WFC ACCUM WFC2-ORA FR782N 7510 2 none none none 3 1361.0 S MP 13639( 6) - 28-Aug-2015 16:07:31 - [ 6] Visit: 02 Visit Requirements: SCHED 60% 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 SGASJ115201 ACS/WFC ACCUM WFC2-ORAM FR601N 6235 FLASH=25 1 1300 S GS ACQ SCENARIO BASE1B3; +331347 P see below PATTERN 5 1 (5260 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 SGASJ115201 ACS/WFC ACCUM WFC2-ORAM FR601N 6235 FLASH=25 1 1300 S PATTERN 6 2 +331347 P see below (2723 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 | ------------------------------------------------------------------------------------------------------------------------------------ SGASJ115201+331347 1 ACS/WFC ACCUM WFC2-ORA FR601N 6235 1 none none none 1 1267.0 S MP SGASJ115201+331347 1 ACS/WFC ACCUM WFC2-ORA FR601N 6235 2 none none none 1 1267.0 S MP SGASJ115201+331347 1 ACS/WFC ACCUM WFC2-ORA FR601N 6235 3 none none none 2 1363.0 S MP SGASJ115201+331347 1 ACS/WFC ACCUM WFC2-ORA FR601N 6235 4 none none none 2 1363.0 S MP SGASJ115201+331347 2 ACS/WFC ACCUM WFC2-ORA FR601N 6235 1 none none none 3 1367.0 S MP SGASJ115201+331347 2 ACS/WFC ACCUM WFC2-ORA FR601N 6235 2 none none none 3 1356.0 S MP 13639( 6) - 28-Aug-2015 16:07:31 - [ 7] Visit: 03 Visit Requirements: SCHED 50% 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 SGASJ134331 ACS/WFC ACCUM WFC1-IRAM FR716N 7270 FLASH=25 1 1320 S GS ACQ SCENARIO BASE1B3; +415455 P see below PATTERN 5 1 (5378 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 | ------------------------------------------------------------------------------------------------------------------------------------ SGASJ134331+415455 1 ACS/WFC ACCUM WFC1-IRA FR716N 7270 1 none none none 1 1296.0 S MP SGASJ134331+415455 1 ACS/WFC ACCUM WFC1-IRA FR716N 7270 2 none none none 1 1296.0 S MP SGASJ134331+415455 1 ACS/WFC ACCUM WFC1-IRA FR716N 7270 3 none none none 2 1393.0 S MP SGASJ134331+415455 1 ACS/WFC ACCUM WFC1-IRA FR716N 7270 4 none none none 2 1393.0 S MP 13639( 6) - 28-Aug-2015 16:07:31 - [ 8] Visit: 04 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 SGASJ162132 ACS/WFC ACCUM WFC2-ORAM FR601N 6230 FLASH=25 1 1300 S PATTERN 5 1 +060705 P see below (5190 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 SGASJ162132 ACS/WFC ACCUM WFC2-ORAM FR601N 6230 FLASH=25 1 1300 S PATTERN 6 2 +060705 P see below (2688 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 | ------------------------------------------------------------------------------------------------------------------------------------ SGASJ162132+060705 1 ACS/WFC ACCUM WFC2-ORA FR601N 6230 1 none none none 1 1249.0 S MP SGASJ162132+060705 1 ACS/WFC ACCUM WFC2-ORA FR601N 6230 2 none none none 1 1249.0 S MP SGASJ162132+060705 1 ACS/WFC ACCUM WFC2-ORA FR601N 6230 3 none none none 2 1346.0 S MP SGASJ162132+060705 1 ACS/WFC ACCUM WFC2-ORA FR601N 6230 4 none none none 2 1346.0 S MP SGASJ162132+060705 2 ACS/WFC ACCUM WFC2-ORA FR601N 6230 1 none none none 3 1341.0 S MP SGASJ162132+060705 2 ACS/WFC ACCUM WFC2-ORA FR601N 6230 2 none none none 3 1347.0 S MP 13639( 6) - 28-Aug-2015 16:07:31 - [ 9] Visit: 05 Visit Requirements: SCHED 40% On Hold Comments: Additional Comments: This target/visit is the one that I am most incertain about re: the dither patterns, as I had to create a second small-scale dither line pattern. My goal (in using Pattern 7 here) was to achieve a subpixel dither that is orthogonal to the pre-defined "ACS-WFC-DITHER-LINE" pattern. 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 RCS1J022431 ACS/WFC ACCUM WFC1-IRAM FR716N 7149 FLASH=25 1 600 S GS ACQ SCENARIO BASE1B3; -0002.5C P see below PATTERN 6 1 (1129 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 RCS1J022431 ACS/WFC ACCUM WFC F850LP FLASH=25 1 500 S PATTERN 6 2 -0002.5C see below (929 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 RCS1J022431 ACS/WFC ACCUM WFC1-IRAM FR716N 7149 FLASH=25 1 600 S PATTERN 7 3 -0002.5C P see below (1170 S) ------------------------------------------------------------------------------------------------------------------------------------ 4 RCS1J022431 ACS/WFC ACCUM WFC F850LP FLASH=25 1 525 S PATTERN 7 4 -0002.5C see below (1020 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 | ------------------------------------------------------------------------------------------------------------------------------------ RCS1J022431-0002.5C 1 ACS/WFC ACCUM WFC1-IRA FR716N 7149 1 none none none 1 534.0 S MP RCS1J022431-0002.5C 1 ACS/WFC ACCUM WFC1-IRA FR716N 7149 2 none none none 1 595.0 S MP RCS1J022431-0002.5C 2 ACS/WFC ACCUM WFC F850LP 1 none none none 1 434.0 S RCS1J022431-0002.5C 2 ACS/WFC ACCUM WFC F850LP 2 none none none 1 495.0 S RCS1J022431-0002.5C 3 ACS/WFC ACCUM WFC1-IRA FR716N 7149 1 none none none 2 585.0 S MP RCS1J022431-0002.5C 3 ACS/WFC ACCUM WFC1-IRA FR716N 7149 2 none none none 2 585.0 S MP RCS1J022431-0002.5C 4 ACS/WFC ACCUM WFC F850LP 1 none none none 2 510.0 S RCS1J022431-0002.5C 4 ACS/WFC ACCUM WFC F850LP 2 none none none 2 510.0 S 13639( 6) - 28-Aug-2015 16:07:31 - [ 10] Visit: 06 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 SGASJ105038 ACS/WFC ACCUM WFC1-IRAM FR716N 7134 FLASH=25 1 1350 S PATTERN 5 1 +001715 P see below (5190 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 | ------------------------------------------------------------------------------------------------------------------------------------ SGASJ105038+001715 1 ACS/WFC ACCUM WFC1-IRA FR716N 7134 1 none none none 1 1249.0 S MP SGASJ105038+001715 1 ACS/WFC ACCUM WFC1-IRA FR716N 7134 2 none none none 1 1249.0 S MP SGASJ105038+001715 1 ACS/WFC ACCUM WFC1-IRA FR716N 7134 3 none none none 2 1346.0 S MP SGASJ105038+001715 1 ACS/WFC ACCUM WFC1-IRA FR716N 7134 4 none none none 2 1346.0 S MP 13639( 6) - 28-Aug-2015 16:07:31 - [ 11] Summary Form for Proposal 13639 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures WFC, WFC1-IRAMP, WFC2-ORAMP ------------------------------------------------------------------------------------------------------------------------------------ Configurations ACS/WFC ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters FLASH=25 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements GS ACQ SCENARIO BASE1B3, PATTERN 5 1, PATTERN 6 1, PATTERN 6 2, PATTERN 7 3, PATTERN 7 4, SCHED 40%, SCHED 50%, SCHED 60% ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F850LP, FR601N, FR716N, FR782N ------------------------------------------------------------------------------------------------------------------------------------ Target Names RCS1J022431-0002.5C, SGASJ091541+382655, SGASJ105038+001715, SGASJ115201+331347, SGASJ134331+415455, SGASJ162132+060705 ------------------------------------------------------------------------------------------------------------------------------------