15696( 7) - 15-May-2019 20:52:10 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 15696 Version: 7 Check-in Time: 15-May-2019 20:52:10 STScI Edit Number: 2 Title Constraints on the physical origins of Lyman-alpha halos at z>4 from giant gravitational arcs ------------------------------------------------------------------------------------ Type Cycle GO 26 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. David Carton Centre de Recherche Astrophysique de Lyon Y CoI: Dr. Johan Pierre Richard Centre de Recherche Astrophysique de Lyon Y CoI: Ms. Adelaide Marie Claeyssens Centre de Recherche Astrophysique de Lyon N CoI: Dr. David Lagattuta Centre de Recherche Astrophysique de Lyon N CoI: Mr. Johany Martinez Centre de Recherche Astrophysique de Lyon N CoI: Dr. Floriane Leclercq Centre de Recherche Astrophysique de Lyon N CoI: Dr. Harald Ebeling University of Hawaii N ------------------------------------------------------------------------------------ Abstract Recent deep integral-field spectroscopy observations using VLT/MUSE revealed two high-redshift (z>4) lensed arcs in the galaxy cluster MACS0940. Notably, both lensed galaxies show highly extended Lyman-alpha emission (> 5 arcsec). These are very rare sources indeed, with only three other such systems known to date. However, truly exceptional is the fact that one of these galaxies forms an almost complete Einstein ring, with the Lyman-alpha arc reaching an unrivaled extent of 30 arcsec. Moreover, the MUSE spectroscopy of this object has identified distinct large-scale spatial variations in the Lyman-alpha line profile. While this object is very unusual from an observational perspective, it shares many intrinsic properties with other, typical, unlensed Lyman-alpha emitters, thus providing an unbiased testbed for distinguishing the different scenarios that have been proposed to explain the origin of Lyman-alpha halos: (a) scattering of the Lyman-alpha emission by neutral gas, (b) cold streams feeding the circumgalactic medium (CGM) and shining in Lyman alpha, and/or (c) the presence of satellite galaxies surrounding the main source of emission. Using multi-band HST photometry in the rest-frame UV, we will map the star-formation activity in both Lyman-alpha arcs. By correlating the results with the Lyman-alpha properties observed with MUSE, and leveraging the magnification boost from the galaxy cluster, we will be able to empirically test the different scenarios. ------------------------------------------------------------------------------------ Observations Description ------------------------ Observations of galaxy cluster MACS0940 in three filter bands. F814W (3 orbits), F125W (1 orbit) and F160W (1 orbit). Pointing chosen to cover MUSE 1'x1' FoV within a single WFC chip Roll angle constraints for F814W are required to avoid bright star. Each orbit contains 2 exposures with a small dither. ------------------------------------------------------------------------------------ 15696( 7) - 15-May-2019 20:52:10 - [ 2] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 MACS0940 CLUSTER OF GALAXIES, RA=09H40M53.6000S, J2000 V = 18.44 +/- 0.05 Primary target EINSTEIN RING, DEC=+07D44'24.90" (System 1 arc): V-Magnitude = 22.27 +/- GRAVITATIONAL LENS 0.1 Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 2 MACS0940-ACS CLUSTER OF GALAXIES, RA=09H40M53.6960S, J2000 V = 18.44 +/- 0.05 Primary target EINSTEIN RING, DEC=+07D44'24.90" (System 1 arc): V-Magnitude = 22.27 +/- GRAVITATIONAL LENS 0.1 Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 15696( 7) - 15-May-2019 20:52:10 - [ 3] Patterns ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 3 Primary_Pattern Secondary_Pattern Pattern_Type ACS-WFC-DITHER-LINE ACS-WFC-DITHER-LINE Pattern_Purpose DITHER DITHER Number_Of_Points 3 2 Point_Spacing 3.034 0.149 Line_Spacing Coordinate_Frame POS-TARG POS-TARG Pattern_Orient 85.29 34.25 Angle_Between_Sides Center_Pattern NO NO ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 2 Primary_Pattern Secondary_Pattern Pattern_Type WFC3-IR-DITHER-LINE Pattern_Purpose DITHER Number_Of_Points 2 Point_Spacing 0.636 Line_Spacing Coordinate_Frame POS-TARG Pattern_Orient 41.788 Angle_Between_Sides Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 4 Primary_Pattern Secondary_Pattern Pattern_Type WFC3-IR-DITHER-LINE Pattern_Purpose DITHER Number_Of_Points 2 Point_Spacing 2.088 Line_Spacing Coordinate_Frame POS-TARG Pattern_Orient 41.788 Angle_Between_Sides Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ 15696( 7) - 15-May-2019 20:52:10 - [ 4] Visit: 01 Visit Requirements: ORIENT 45D TO 135 D 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 MACS0940-AC ACS/WFC ACCUM WFC1 F814W 1 1000 S PATTERN 3 1 S see below (7526 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 | ------------------------------------------------------------------------------------------------------------------------------------ MACS0940-ACS 1 ACS/WFC ACCUM WFC1 F814W 1 1 none none 1 1217.0 S MACS0940-ACS 1 ACS/WFC ACCUM WFC1 F814W 1 2 none none 1 1217.0 S MACS0940-ACS 1 ACS/WFC ACCUM WFC1 F814W 2 1 none none 2 1273.0 S MACS0940-ACS 1 ACS/WFC ACCUM WFC1 F814W 2 2 none none 2 1273.0 S MACS0940-ACS 1 ACS/WFC ACCUM WFC1 F814W 3 1 none none 3 1273.0 S MACS0940-ACS 1 ACS/WFC ACCUM WFC1 F814W 3 2 none none 3 1273.0 S 15696( 7) - 15-May-2019 20:52:10 - [ 5] Visit: 02 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 MACS0940 WFC3/IR MULTIAC IR F125W NSAMP=14, SAMP-SEQ=SPARS100 1 DEF PATTERN 2 1 CUM (2605.873 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 | ------------------------------------------------------------------------------------------------------------------------------------ MACS0940 1 WFC3/IR MULTIAC IR F125W 1 none none none 1 N/A CUM MACS0940 1 WFC3/IR MULTIAC IR F125W 2 none none none 1 N/A CUM 15696( 7) - 15-May-2019 20:52:10 - [ 6] Visit: 03 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 MACS0940 WFC3/IR MULTIAC IR F160W NSAMP=14, SAMP-SEQ=SPARS100 1 DEF POS TARG -0.82, null; CUM (2605.873 PATTERN 2 1 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 | ------------------------------------------------------------------------------------------------------------------------------------ MACS0940 1 WFC3/IR MULTIAC IR F160W 1 none none none 1 N/A CUM MACS0940 1 WFC3/IR MULTIAC IR F160W 2 none none none 1 N/A CUM 15696( 7) - 15-May-2019 20:52:10 - [ 7] Visit: 63 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 MACS0940 WFC3/IR MULTIAC IR F160W NSAMP=14, SAMP-SEQ=SPARS100 1 DEF POS TARG null, -0.79; GS CUM (2605.873 ACQ SCENARIO BASE1B3; S) PATTERN 4 1 ------------------------------------------------------------------------------------------------------------------------------------ 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 | ------------------------------------------------------------------------------------------------------------------------------------ MACS0940 1 WFC3/IR MULTIAC IR F160W 1 none none none 1 N/A CUM MACS0940 1 WFC3/IR MULTIAC IR F160W 2 none none none 1 N/A CUM 15696( 7) - 15-May-2019 20:52:10 - [ 8] Summary Form for Proposal 15696 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures IR, WFC1 ------------------------------------------------------------------------------------------------------------------------------------ Configurations ACS/WFC, WFC3/IR ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM, MULTIACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters NSAMP=14, SAMP-SEQ=SPARS100 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements GS ACQ SCENARIO BASE1B3, ORIENT 45D TO 135 D, PATTERN 2 1, PATTERN 3 1, PATTERN 4 1, POS TARG -0.82, null, POS TARG null, -0.79 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F125W, F160W, F814W ------------------------------------------------------------------------------------------------------------------------------------ Target Names MACS0940, MACS0940-ACS ------------------------------------------------------------------------------------------------------------------------------------