17119( 2) - 15-Jul-2022 15:11:57 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 17119 Version: 2 Check-in Time: 15-Jul-2022 15:11:57 STScI Edit Number: 0 Title Completing the stellar census of Westerlund 1 ------------------------------------------------------------------------------------ Type Cycle GO 30 ------------------------------------------------------------------------------------ Investigators Contact? PI: Prof. Quinn Konopacky University of California - San Diego Y CoI: Lingfeng Wei University of California - San Diego N CoI: Dr. Jessica Ryan Lu University of California - Berkeley N CoI: Dr. Christopher Theissen University of California - San Diego N CoI: Dr. Matthew Hosek Jr. University of California - Los Angeles N ------------------------------------------------------------------------------------ Abstract We propose to obtain a new epoch of precise astrometry covering a 4'x4' extent of the massive, young cluster Westerlund 1. Previous epochs of HST data have been used to determine cluster membership for the full cluster down to a mass limit of 1.4 Msun using proper motions derived from a combination of optical and near infrared data. By adding an additional epoch of astrometry from WFC3-IR, we will be able to confirm the full membership of the cluster down to 0.1 Msun. These observations will be used to map the full initial mass function (IMF) of the cluster, which we have tentatively found is bottom-light. Furthermore, the additional epoch of data will offer an improvement in proper motion precision by a factor of 3, enabling the measurement of velocities to ~1 km/s. Using this information, we will map the velocities as a function of mass to test star formation models. These data will provide new insight into the origin and universality of the IMF. ------------------------------------------------------------------------------------ Observations Description ------------------------ Our program to measure the internal kinematics of the massive young cluster, Westerlund 1, requires precise astrometric observations. Archival HST data sets of Wd 1 include three epochs multi-band WFC3-IR imaging of the full extent of the cluster, which we will use as our initial epochs. New observations in cycle 30 will provide a critical fourth near-infrared astrometric epochs, providing membership confirmation and precise velocities down to the substellar limit. A 2x2 (4'x4') mosaic is needed to cover the full cluster extent. Our target goal is to identify and measure cluster members down to the limits of the existing WFC3-IR data at 0.1 solar masses, which corresponds to H=20.5. In order to effectively select the field stars, we require a 1 sigma proper motion precision of <0.3 mas/yr. We will use existing data from 2010, 2013, and 2015 with a total time baseline of 12 years to achieve our desired proper motion errors. We will measure the astrometry with WFC3's longest-wavelength filter (F160W) to minimize the impact of extinction. Therefore, we need a total SNR=160 on the stars of interest to achieve an astrometric precision of 1 mas and a final velocity precision of 0.1 mas/yr. Additionally, to minimize the impact of geometric distortions, we request that the astrometric observations have the SAME ORIENT with small POSTARG offsets as the 2013 and 2015 17119( 2) - 15-Jul-2022 15:11:57 - [ 2] observations. Our observations require a high dynamic range as we are interested in both the higher mass, brighter stars (typically H=0) and the lower mass, fainter stars (typically H=20.5) in the cluster. As a result we must limit our integration time per exposure so as to avoid saturating too many stars, such that the resulting persistence images would not impact the astrometric measurements. We also adopt a minimum integration time that still allows us to dump the WFC3 buffer in parallel (249 s for a STEP50 readout pattern with 10 MULTIACCUM reads). Integration times for observations of Wd 1 in the F160W filter were calculated with the WFC3 exposure time calculator to achieve SNR=160 for an H=20.5 star with a late M dwarf spectral type and an E(B-V) = 3.5. For each position in our proposed 2x2 mosaic of Wd 1, we require 13-14 exposures for a total of 3240-3490 s of integration time per pointing. We also require additional short exposures in sub-arrayed mode to capture the most massive stars that were saturated in the longer exposures. This amounts to 7 orbits to complete the entire mosaic in cycle 30. --------- Additional Comments ---------- The archival observations have the PID 11708 from 2010 and PID 13809 from 2013/2015. We request that our new observations have the same orientation and detector position as the F160W images from the archived data set. ------------------------------------------------------------------------------------ 17119( 2) - 15-Jul-2022 15:11:57 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 CL-WESTERLUN STELLAR CLUSTER, OB RA=16H47M4.0000S +/- 0.1", J2000 V = 12 H=9-20 D-1 ASSOCIATION, OPEN DEC=-45D50'42.00" +/- 0.1" CLUSTER, STAR FORMING REGION, YOUNG ASSOCIATION Reference Frame: Other: SIMBAD Comments: This object was generated by the targetselector and retrieved from the SIMBAD database. Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) 2015.5 -2.2253430573750216E-4 -0.0036540000337481615 0.0 ------------------------------------------------------------------------------------------------------------------------------------ 17119( 2) - 15-Jul-2022 15:11:57 - [ 4] Patterns ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 1 Primary_Pattern Secondary_Pattern Pattern_Type SPIRAL Pattern_Purpose DITHER Number_Of_Points 14 Point_Spacing 3.26 Line_Spacing Coordinate_Frame POS-TARG Pattern_Orient 14 Angle_Between_Sides Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 2 Primary_Pattern Secondary_Pattern Pattern_Type SPIRAL Pattern_Purpose DITHER Number_Of_Points 13 Point_Spacing 3.26 Line_Spacing Coordinate_Frame POS-TARG Pattern_Orient 14 Angle_Between_Sides Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ 17119( 2) - 15-Jul-2022 15:11:57 - [ 5] Visit: 01 Visit Requirements: ORIENT 265D TO 275 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 CL-WESTERLU WFC3/IR MULTIAC IRSUB512- F160W SAMP-SEQ=RAPID, NSAMP=10 1 DEF (8.53 POS TARG 24.2, -21 ND-1 CUM FIX S) ------------------------------------------------------------------------------------------------------------------------------------ 2 CL-WESTERLU WFC3/IR MULTIAC IRSUB512- F160W SAMP-SEQ=RAPID, NSAMP=10 1 DEF (8.53 POS TARG 85.8, -21 ND-1 CUM FIX S) ------------------------------------------------------------------------------------------------------------------------------------ 3 CL-WESTERLU WFC3/IR MULTIAC IRSUB512- F160W SAMP-SEQ=RAPID, NSAMP=10 1 DEF (8.53 POS TARG 24.2, 21 ND-1 CUM FIX S) ------------------------------------------------------------------------------------------------------------------------------------ 4 CL-WESTERLU WFC3/IR MULTIAC IRSUB512- F160W SAMP-SEQ=RAPID, NSAMP=10 1 DEF (8.53 POS TARG 85.8, 21 ND-1 CUM FIX S) ------------------------------------------------------------------------------------------------------------------------------------ 5 CL-WESTERLU WFC3/IR MULTIAC IR-FIX F160W SAMP-SEQ=STEP50, NSAMP=10 1 DEF POS TARG 55, -55; ND-1 CUM (3240.016 PATTERN 2 5 S) ------------------------------------------------------------------------------------------------------------------------------------ 6 CL-WESTERLU WFC3/IR MULTIAC IR-FIX F160W SAMP-SEQ=STEP50, NSAMP=10 1 DEF POS TARG 55, 55; PATTERN ND-1 CUM (3240.016 2 6 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 | ------------------------------------------------------------------------------------------------------------------------------------ CL-WESTERLUND-1 1 WFC3/IR MULTIAC IRSUB512 F160W none none none none 1 N/A CUM -FIX CL-WESTERLUND-1 2 WFC3/IR MULTIAC IRSUB512 F160W none none none none 1 N/A CUM -FIX CL-WESTERLUND-1 3 WFC3/IR MULTIAC IRSUB512 F160W none none none none 1 N/A CUM -FIX CL-WESTERLUND-1 4 WFC3/IR MULTIAC IRSUB512 F160W none none none none 1 N/A CUM -FIX CL-WESTERLUND-1 5 WFC3/IR MULTIAC IR-FIX F160W 1 none none none 1 N/A CUM CL-WESTERLUND-1 5 WFC3/IR MULTIAC IR-FIX F160W 2 none none none 1 N/A CUM CL-WESTERLUND-1 5 WFC3/IR MULTIAC IR-FIX F160W 3 none none none 1 N/A CUM CL-WESTERLUND-1 5 WFC3/IR MULTIAC IR-FIX F160W 4 none none none 1 N/A CUM 17119( 2) - 15-Jul-2022 15:11:57 - [ 6] 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 | ------------------------------------------------------------------------------------------------------------------------------------ CL-WESTERLUND-1 5 WFC3/IR MULTIAC IR-FIX F160W 5 none none none 1 N/A CUM CL-WESTERLUND-1 5 WFC3/IR MULTIAC IR-FIX F160W 6 none none none 1 N/A CUM CL-WESTERLUND-1 5 WFC3/IR MULTIAC IR-FIX F160W 7 none none none 1 N/A CUM CL-WESTERLUND-1 5 WFC3/IR MULTIAC IR-FIX F160W 8 none none none 1 N/A CUM CL-WESTERLUND-1 5 WFC3/IR MULTIAC IR-FIX F160W 9 none none none 2 N/A CUM CL-WESTERLUND-1 5 WFC3/IR MULTIAC IR-FIX F160W 10 none none none 2 N/A CUM CL-WESTERLUND-1 5 WFC3/IR MULTIAC IR-FIX F160W 11 none none none 2 N/A CUM CL-WESTERLUND-1 5 WFC3/IR MULTIAC IR-FIX F160W 12 none none none 2 N/A CUM CL-WESTERLUND-1 5 WFC3/IR MULTIAC IR-FIX F160W 13 none none none 2 N/A CUM CL-WESTERLUND-1 6 WFC3/IR MULTIAC IR-FIX F160W 1 none none none 2 N/A CUM CL-WESTERLUND-1 6 WFC3/IR MULTIAC IR-FIX F160W 2 none none none 2 N/A CUM CL-WESTERLUND-1 6 WFC3/IR MULTIAC IR-FIX F160W 3 none none none 2 N/A CUM CL-WESTERLUND-1 6 WFC3/IR MULTIAC IR-FIX F160W 4 none none none 2 N/A CUM CL-WESTERLUND-1 6 WFC3/IR MULTIAC IR-FIX F160W 5 none none none 3 N/A CUM CL-WESTERLUND-1 6 WFC3/IR MULTIAC IR-FIX F160W 6 none none none 3 N/A CUM CL-WESTERLUND-1 6 WFC3/IR MULTIAC IR-FIX F160W 7 none none none 3 N/A CUM CL-WESTERLUND-1 6 WFC3/IR MULTIAC IR-FIX F160W 8 none none none 3 N/A CUM CL-WESTERLUND-1 6 WFC3/IR MULTIAC IR-FIX F160W 9 none none none 3 N/A CUM CL-WESTERLUND-1 6 WFC3/IR MULTIAC IR-FIX F160W 10 none none none 3 N/A CUM CL-WESTERLUND-1 6 WFC3/IR MULTIAC IR-FIX F160W 11 none none none 3 N/A CUM CL-WESTERLUND-1 6 WFC3/IR MULTIAC IR-FIX F160W 12 none none none 3 N/A CUM CL-WESTERLUND-1 6 WFC3/IR MULTIAC IR-FIX F160W 13 none none none 3 N/A CUM 17119( 2) - 15-Jul-2022 15:11:57 - [ 7] Visit: 02 Visit Requirements: SAME ORIENT AS 01; AFTER 01 BY 0 D TO 30 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 CL-WESTERLU WFC3/IR MULTIAC IRSUB512- F160W SAMP-SEQ=RAPID, NSAMP=10 1 DEF (8.53 POS TARG -85.8, 21 ND-1 CUM FIX S) ------------------------------------------------------------------------------------------------------------------------------------ 2 CL-WESTERLU WFC3/IR MULTIAC IRSUB512- F160W SAMP-SEQ=RAPID, NSAMP=10 1 DEF (8.53 POS TARG -24.1, 21 ND-1 CUM FIX S) ------------------------------------------------------------------------------------------------------------------------------------ 3 CL-WESTERLU WFC3/IR MULTIAC IRSUB512- F160W SAMP-SEQ=RAPID, NSAMP=10 1 DEF (8.53 POS TARG -85.8, -21 ND-1 CUM FIX S) ------------------------------------------------------------------------------------------------------------------------------------ 4 CL-WESTERLU WFC3/IR MULTIAC IRSUB512- F160W SAMP-SEQ=RAPID, NSAMP=10 1 DEF (8.53 POS TARG -24.2, -21 ND-1 CUM FIX S) ------------------------------------------------------------------------------------------------------------------------------------ 5 CL-WESTERLU WFC3/IR MULTIAC IR-FIX F160W SAMP-SEQ=STEP50, NSAMP=10 1 DEF POS TARG -55, 55; ND-1 CUM (3240.016 PATTERN 2 5 S) ------------------------------------------------------------------------------------------------------------------------------------ 6 CL-WESTERLU WFC3/IR MULTIAC IR-FIX F160W SAMP-SEQ=STEP50, NSAMP=10 1 DEF POS TARG -55, -55; ND-1 CUM (3489.248 PATTERN 1 6 S) ------------------------------------------------------------------------------------------------------------------------------------ 7 CL-WESTERLU WFC3/IR MULTIAC IRSUB512- F160W SAMP-SEQ=RAPID, NSAMP=10 1 DEF (8.53 POS TARG 24.2, 89 ND-1 CUM FIX S) ------------------------------------------------------------------------------------------------------------------------------------ 8 CL-WESTERLU WFC3/IR MULTIAC IRSUB512- F160W SAMP-SEQ=RAPID, NSAMP=10 1 DEF (8.53 POS TARG -24.2, 89 ND-1 CUM FIX S) ------------------------------------------------------------------------------------------------------------------------------------ 9 CL-WESTERLU WFC3/IR MULTIAC IRSUB512- F160W SAMP-SEQ=RAPID, NSAMP=10 1 DEF (8.53 POS TARG -85.8, 89 ND-1 CUM FIX S) ------------------------------------------------------------------------------------------------------------------------------------ 10 CL-WESTERLU WFC3/IR MULTIAC IRSUB512- F160W SAMP-SEQ=RAPID, NSAMP=10 1 DEF (8.53 POS TARG -85.8, -89 ND-1 CUM FIX S) ------------------------------------------------------------------------------------------------------------------------------------ 11 CL-WESTERLU WFC3/IR MULTIAC IRSUB512- F160W SAMP-SEQ=RAPID, NSAMP=10 1 DEF (8.53 POS TARG -24.2, -89 ND-1 CUM FIX S) ------------------------------------------------------------------------------------------------------------------------------------ 12 CL-WESTERLU WFC3/IR MULTIAC IRSUB512- F160W SAMP-SEQ=RAPID, NSAMP=10 1 DEF (8.53 POS TARG 24.2, -89 ND-1 CUM FIX S) ------------------------------------------------------------------------------------------------------------------------------------ 13 CL-WESTERLU WFC3/IR MULTIAC IRSUB512- F160W SAMP-SEQ=RAPID, NSAMP=10 1 DEF (8.53 POS TARG 85.8, -89 ND-1 CUM FIX S) ------------------------------------------------------------------------------------------------------------------------------------ 17119( 2) - 15-Jul-2022 15:11:57 - [ 8] 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 | ------------------------------------------------------------------------------------------------------------------------------------ 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 | ------------------------------------------------------------------------------------------------------------------------------------ CL-WESTERLUND-1 1 WFC3/IR MULTIAC IRSUB512 F160W none none none none 1 N/A CUM -FIX CL-WESTERLUND-1 2 WFC3/IR MULTIAC IRSUB512 F160W none none none none 1 N/A CUM -FIX CL-WESTERLUND-1 3 WFC3/IR MULTIAC IRSUB512 F160W none none none none 1 N/A CUM -FIX CL-WESTERLUND-1 4 WFC3/IR MULTIAC IRSUB512 F160W none none none none 1 N/A CUM -FIX CL-WESTERLUND-1 5 WFC3/IR MULTIAC IR-FIX F160W 1 none none none 1 N/A CUM CL-WESTERLUND-1 5 WFC3/IR MULTIAC IR-FIX F160W 2 none none none 1 N/A CUM CL-WESTERLUND-1 5 WFC3/IR MULTIAC IR-FIX F160W 3 none none none 1 N/A CUM CL-WESTERLUND-1 5 WFC3/IR MULTIAC IR-FIX F160W 4 none none none 1 N/A CUM CL-WESTERLUND-1 5 WFC3/IR MULTIAC IR-FIX F160W 5 none none none 1 N/A CUM CL-WESTERLUND-1 5 WFC3/IR MULTIAC IR-FIX F160W 6 none none none 1 N/A CUM CL-WESTERLUND-1 5 WFC3/IR MULTIAC IR-FIX F160W 7 none none none 1 N/A CUM CL-WESTERLUND-1 5 WFC3/IR MULTIAC IR-FIX F160W 8 none none none 1 N/A CUM CL-WESTERLUND-1 5 WFC3/IR MULTIAC IR-FIX F160W 9 none none none 2 N/A CUM CL-WESTERLUND-1 5 WFC3/IR MULTIAC IR-FIX F160W 10 none none none 2 N/A CUM CL-WESTERLUND-1 5 WFC3/IR MULTIAC IR-FIX F160W 11 none none none 2 N/A CUM CL-WESTERLUND-1 5 WFC3/IR MULTIAC IR-FIX F160W 12 none none none 2 N/A CUM CL-WESTERLUND-1 5 WFC3/IR MULTIAC IR-FIX F160W 13 none none none 2 N/A CUM CL-WESTERLUND-1 6 WFC3/IR MULTIAC IR-FIX F160W 1 none none none 2 N/A CUM CL-WESTERLUND-1 6 WFC3/IR MULTIAC IR-FIX F160W 2 none none none 2 N/A CUM CL-WESTERLUND-1 6 WFC3/IR MULTIAC IR-FIX F160W 3 none none none 2 N/A CUM CL-WESTERLUND-1 6 WFC3/IR MULTIAC IR-FIX F160W 4 none none none 2 N/A CUM 17119( 2) - 15-Jul-2022 15:11:57 - [ 9] 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 | ------------------------------------------------------------------------------------------------------------------------------------ CL-WESTERLUND-1 6 WFC3/IR MULTIAC IR-FIX F160W 5 none none none 3 N/A CUM CL-WESTERLUND-1 6 WFC3/IR MULTIAC IR-FIX F160W 6 none none none 3 N/A CUM CL-WESTERLUND-1 6 WFC3/IR MULTIAC IR-FIX F160W 7 none none none 3 N/A CUM CL-WESTERLUND-1 6 WFC3/IR MULTIAC IR-FIX F160W 8 none none none 3 N/A CUM CL-WESTERLUND-1 6 WFC3/IR MULTIAC IR-FIX F160W 9 none none none 3 N/A CUM CL-WESTERLUND-1 6 WFC3/IR MULTIAC IR-FIX F160W 10 none none none 3 N/A CUM CL-WESTERLUND-1 6 WFC3/IR MULTIAC IR-FIX F160W 11 none none none 3 N/A CUM CL-WESTERLUND-1 6 WFC3/IR MULTIAC IR-FIX F160W 12 none none none 3 N/A CUM CL-WESTERLUND-1 6 WFC3/IR MULTIAC IR-FIX F160W 13 none none none 3 N/A CUM CL-WESTERLUND-1 6 WFC3/IR MULTIAC IR-FIX F160W 14 none none none 4 N/A CUM CL-WESTERLUND-1 7 WFC3/IR MULTIAC IRSUB512 F160W none none none none 4 N/A CUM -FIX CL-WESTERLUND-1 8 WFC3/IR MULTIAC IRSUB512 F160W none none none none 4 N/A CUM -FIX CL-WESTERLUND-1 9 WFC3/IR MULTIAC IRSUB512 F160W none none none none 4 N/A CUM -FIX CL-WESTERLUND-1 10 WFC3/IR MULTIAC IRSUB512 F160W none none none none 4 N/A CUM -FIX CL-WESTERLUND-1 11 WFC3/IR MULTIAC IRSUB512 F160W none none none none 4 N/A CUM -FIX CL-WESTERLUND-1 12 WFC3/IR MULTIAC IRSUB512 F160W none none none none 4 N/A CUM -FIX CL-WESTERLUND-1 13 WFC3/IR MULTIAC IRSUB512 F160W none none none none 4 N/A CUM -FIX 17119( 2) - 15-Jul-2022 15:11:57 - [ 10] Summary Form for Proposal 17119 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures IR-FIX, IRSUB512-FIX ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFC3/IR ------------------------------------------------------------------------------------------------------------------------------------ Opmodes MULTIACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters NSAMP=10, SAMP-SEQ=RAPID, SAMP-SEQ=STEP50 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements AFTER 01 BY 0 D TO 30 D, ORIENT 265D TO 275 D, PATTERN 1 6, PATTERN 2 5, PATTERN 2 6, POS TARG -24.1, 21, POS TARG -24.2, -21, POS TARG -24.2, -89, POS TARG -24.2, 89, POS TARG -55, -55, POS TARG -55, 55, POS TARG -85.8, -21, POS TARG -85.8, -89, POS TARG -85.8, 21, POS TARG -85.8, 89, POS TARG 24.2, -21, POS TARG 24.2, -89, POS TARG 24.2, 21, POS TARG 24.2, 89, POS TARG 55, -55, POS TARG 55, 55, POS TARG 85.8, -21, POS TARG 85.8, -89, POS TARG 85.8, 21, SAME ORIENT AS 01 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F160W ------------------------------------------------------------------------------------------------------------------------------------ Target Names CL-WESTERLUND-1 ------------------------------------------------------------------------------------------------------------------------------------