14725( 2) - 18-Jul-2016 19:33:50 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 14725 Version: 2 Check-in Time: 18-Jul-2016 19:33:50 STScI Edit Number: 0 Title Hunting for Brown Dwarfs in Globular Clusters: Second Epoch Deep IR observations of the Globular Clusters M4 ------------------------------------------------------------------------------------ Type Cycle GO 24 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. Andrea Dieball Universitat Bonn, Argelander Institute for Y Astronomy CoI: Dr. Luigi R. Bedin Osservatorio Astronomico di Padova N CoI: Prof. Christian Knigge University of Southampton N CoI: Dr. R. Michael Rich University of California - Los Angeles N CoI: Dr. France Allard Centre de Recherche Astronomique de Lyon N CoI: Dr. Aaron L. Dotter Harvard University N CoI: Dr. Harvey B. Richer University of British Columbia N CoI: Dr. David R. Zurek American Museum of Natural History N ------------------------------------------------------------------------------------ Abstract We propose to obtain a second epoch of deep WFC3/F110W imaging of the globular cluster M4 to confirm (or rule out) the first brown dwarfs (BDs) detected in this cluster. In a first epoch of deep WFC3 IR imaging of M4, four good BD candidates were identified. We will use a second epoch to test whether the BD candidates share the proper motion of the cluster population or not, thereby confirming (or ruling out) these sources as genuine cluster members. Confirming these sources as cluster BDs is crucial if we want to fill the observational plane with old and metal-poor benchmark sources that are much needed if we are to test and calibrate models about BD atmospheres, BD formation and evolution. ------------------------------------------------------------------------------------ Observations Description ------------------------ The observations will be obtained using a dither pattern otpimized to best sample the PSF, and to compensate for detector deficits like hot/cold/dead pixels and the IR blobs, which will improve image quality and resolution. We use POS TARG to implement the dither steps. The observations will be carried out in two visits consisting of 1 orbit each. Both orbits will be done with a NSAMP14 SPARS50 and the four point dither pattern. ------------------------------------------------------------------------------------ 14725( 2) - 18-Jul-2016 19:33:50 - [ 2] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 M-4 STELLAR CLUSTER, RA=16H23M41.7158S, J2000 V = 7.12 GLOBULAR CLUSTER DEC=-26D30'19.01" Reference Frame: ICRS Comments: This object was generated by the targetselector and retrieved from the SIMBAD database, the coordinates were updated to match the coordinates of the first epoch WFC3 F110W observations (GO-12602). ------------------------------------------------------------------------------------------------------------------------------------ 2 M-4-V2 STELLAR CLUSTER, RA=16H23M42.2147S, J2000 V = 7.12 GLOBULAR CLUSTER DEC=-26D30'5.26" Reference Frame: ICRS Comments: This object was generated by the targetselector and retrieved from the SIMBAD database, the coordinates were updated to match the coordinates of the first epoch WFC3 F110W observations (GO-12602) and shifted slightly. ------------------------------------------------------------------------------------------------------------------------------------ 14725( 2) - 18-Jul-2016 19:33:50 - [ 3] Visit: 01 Visit Requirements: ORIENT 296D TO 296 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 M-4 WFC3/IR MULTIAC IR-UVIS-F F110W NSAMP=14, SAMP-SEQ=SPARS50 1 DEF POS TARG -5, 5 CUM IX (652.938 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 M-4 WFC3/IR MULTIAC IR-UVIS-F F110W NSAMP=14, SAMP-SEQ=SPARS50 1 DEF POS TARG -2.5, 2.5 CUM IX (652.938 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 M-4 WFC3/IR MULTIAC IR-UVIS-F F110W NSAMP=14, SAMP-SEQ=SPARS50 1 DEF POS TARG -7.5, 7.5 CUM IX (652.938 S) ------------------------------------------------------------------------------------------------------------------------------------ 4 M-4 WFC3/IR MULTIAC IR-UVIS-F F110W NSAMP=14, SAMP-SEQ=SPARS50 1 DEF CUM IX (652.938 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 | ------------------------------------------------------------------------------------------------------------------------------------ M-4 1 WFC3/IR MULTIAC IR-UVIS- F110W none none none none 1 N/A CUM FIX M-4 2 WFC3/IR MULTIAC IR-UVIS- F110W none none none none 1 N/A CUM FIX M-4 3 WFC3/IR MULTIAC IR-UVIS- F110W none none none none 1 N/A CUM FIX M-4 4 WFC3/IR MULTIAC IR-UVIS- F110W none none none none 1 N/A CUM FIX 14725( 2) - 18-Jul-2016 19:33:50 - [ 4] Visit: 02 Visit Requirements: ORIENT 180D TO 180D FROM 01 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 M-4-V2 WFC3/IR MULTIAC IR-UVIS-F F110W NSAMP=14, SAMP-SEQ=SPARS50 1 DEF POS TARG 2.5, -12.5 CUM IX (652.938 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 M-4-V2 WFC3/IR MULTIAC IR-UVIS-F F110W NSAMP=14, SAMP-SEQ=SPARS50 1 DEF POS TARG 0, -10 CUM IX (652.938 S) ------------------------------------------------------------------------------------------------------------------------------------ 3 M-4-V2 WFC3/IR MULTIAC IR-UVIS-F F110W NSAMP=14, SAMP-SEQ=SPARS50 1 DEF POS TARG -2.5, -7.5 CUM IX (652.938 S) ------------------------------------------------------------------------------------------------------------------------------------ 4 M-4-V2 WFC3/IR MULTIAC IR-UVIS-F F110W NSAMP=14, SAMP-SEQ=SPARS50 1 DEF POS TARG -5, -5 CUM IX (652.938 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 | ------------------------------------------------------------------------------------------------------------------------------------ M-4-V2 1 WFC3/IR MULTIAC IR-UVIS- F110W none none none none 1 N/A CUM FIX M-4-V2 2 WFC3/IR MULTIAC IR-UVIS- F110W none none none none 1 N/A CUM FIX M-4-V2 3 WFC3/IR MULTIAC IR-UVIS- F110W none none none none 1 N/A CUM FIX M-4-V2 4 WFC3/IR MULTIAC IR-UVIS- F110W none none none none 1 N/A CUM FIX 14725( 2) - 18-Jul-2016 19:33:50 - [ 5] Summary Form for Proposal 14725 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures IR-UVIS-FIX ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFC3/IR ------------------------------------------------------------------------------------------------------------------------------------ Opmodes MULTIACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters NSAMP=14, SAMP-SEQ=SPARS50 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ORIENT 180D TO 180D FROM 01, ORIENT 296D TO 296 D, POS TARG -2.5, -7.5, POS TARG -2.5, 2.5, POS TARG -5, -5, POS TARG -5, 5, POS TARG -7.5, 7.5, POS TARG 0, -10, POS TARG 2.5, -12.5 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F110W ------------------------------------------------------------------------------------------------------------------------------------ Target Names M-4, M-4-V2 ------------------------------------------------------------------------------------------------------------------------------------