12602( 3) - 08-Jul-2011 19:34:47 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 12602 Version: 3 Check-in Time: 08-Jul-2011 19:34:47 STScI Edit Number: 0 Title Beyond the Hydrogen-burning limit: Deep IR observations of the Globular Clusters M4 ------------------------------------------------------------------------------------ Type Cycle GO 19 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. Andrea Dieball University of Southampton CoI: Dr. Harvey B. Richer University of British Columbia N CoI: Dr. Christian Knigge University of Southampton N CoI: Dr. Aaron Dotter Space Telescope Science Institute N CoI: Dr. David R. Zurek American Museum of Natural History N CoI: Dr. R. Michael Rich University of California - Los Angeles N ------------------------------------------------------------------------------------ Abstract We propose to use ultra-deep near-infrared imaging with WFC3 in M4 to explore the very lowest mass domain in this globular cluster. We expect to detect the first brown dwarfs in globular clusters, and in fact perhaps the first PopII BDs anywhere. In doing so, we will also explore the hydrogen-burning limit and determine the mass-luminosity relationship around the stellar/sub-stellar border of the main sequence. In addition we will search the cluster white dwarfs for evidence of infrared excess which could herald the presence of a planetary disk or planets themselves. This ultra-deep near-IR data set will allow us to test fundamental physical predictions quantitatively for the first time. This will have important consequences for many astrophysical aspects from stellar structure and evolution, to planet formation in the early Universe, to ages, formation and evolution of GCs. ------------------------------------------------------------------------------------ Observations Description ------------------------ The observations will be obtained using a dither pattern so that the PSF will be well sampled. For our WFC3-IR observations, we chose a WFC3-IR-DITHER-BOX-MIN to best sample the PSF, and for our WFC3-UVIS observations we chose a combination of WFC3-UVIS-GAP-LINE and WFC3-UVIS-LINE-3PT to step over the gap between the two UVIS CCD and to sample the PSF with a 3 point dither. We split our observations into 2 visits with 4 orbits each. The first visit will be spend on 2 orbits F110W followed by 2 orbits on F390W. The first two orbits in F110W will be done with a NSAMP14 SPARS50 and the four point dither pattern. The third and forth orbit will be spent on F390W, with 911 or 922 sec individual exposure times, once on each of the three dither positions (3 exposures per orbit). The second visit will consist of 4 orbits on F160W observations, again with the WFC3-IR-DITHER-BOX-MIN to best sample the PSF, and with the same NSAMP14 SPARS50. Our deep near-IR data will be matched to the already existing optical HST ACS WFC data sets. Thus, we want to have our WFC3 IR observations within the field 12602( 3) - 08-Jul-2011 19:34:47 - [ 2] of view of the existing ACS WFC data, but we also want to avoid the bulk of bright stars that will be saturated in our images. The best orientation angles are thus between 30 - 65 degree or between 290 - 330 degree. The parallel observations will be done with ACS WFC F606W (2 orbits) and ACS WFC F814W (6 orbits). Real Time Justification ----------------------- Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ 12602( 3) - 08-Jul-2011 19:34:47 - [ 3] 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 +/- 0.1", J2000 V = 7.12 GLOBULAR CLUSTER DEC=-26D30'19.01" +/- 0.1" Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 12602( 3) - 08-Jul-2011 19:34:47 - [ 4] Patterns ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 1 Primary_Pattern Secondary_Pattern Pattern_Type WFC3-IR-DITHER-BOX-MIN Pattern_Purpose DITHER Number_Of_Points 4 Point_Spacing 0.572 Line_Spacing 0.365 Coordinate_Frame POS-TARG Pattern_Orient 18.528 Angle_Between_Sides 74.653 Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 2 Primary_Pattern Secondary_Pattern Pattern_Type WFC3-UVIS-GAP-LINE WFC3-UVIS-DITHER-LINE-3PT Pattern_Purpose MOSAIC DITHER Number_Of_Points 2 3 Point_Spacing 2.414 0.135 Line_Spacing Coordinate_Frame POS-TARG POS-TARG Pattern_Orient 85.759 46.84 Angle_Between_Sides Center_Pattern YES NO ------------------------------------------------------------------------------------------------------------------------------------ 12602( 3) - 08-Jul-2011 19:34:47 - [ 5] Visit: 01 Visit Requirements: ORIENT 30D TO 65 D; ORIENT 290D TO 330 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| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 M-4 WFC3/IR MULTIAC IR-UVIS-F F110W NSAMP=14, SAMP-SEQ=SPARS50 1 DEF PATTERN 1 1-2; PAR 2 CUM IX WITH 1 ------------------------------------------------------------------------------------------------------------------------------------ 2 M-4 ACS/WFC ACCUM WFC-FIX F606W 1 350 S see below ------------------------------------------------------------------------------------------------------------------------------------ 3 M-4 WFC3/IR MULTIAC IR-UVIS-F F110W NSAMP=14, SAMP-SEQ=SPARS50 1 DEF PATTERN 1 3-4; PAR 4 CUM IX WITH 3 ------------------------------------------------------------------------------------------------------------------------------------ 4 M-4 ACS/WFC ACCUM WFC-FIX F606W 1 350 S see below ------------------------------------------------------------------------------------------------------------------------------------ 5 M-4 WFC3/UVI ACCUM UVIS-IR-F F390W 1 750 S PATTERN 2 5-6; PAR 6 S IX see below WITH 5 ------------------------------------------------------------------------------------------------------------------------------------ 6 M-4 ACS/WFC ACCUM WFC-FIX F814W 1 600 S see below ------------------------------------------------------------------------------------------------------------------------------------ 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 1 none none none 1 N/A CUM FIX M-4 1 WFC3/IR MULTIAC IR-UVIS- F110W 2 none none none 1 N/A CUM FIX M-4 1 WFC3/IR MULTIAC IR-UVIS- F110W 3 none none none 1 N/A CUM FIX M-4 1 WFC3/IR MULTIAC IR-UVIS- F110W 4 none none none 1 N/A CUM FIX M-4 2 ACS/WFC ACCUM WFC-FIX F606W 1 none none none 1 475.0 S M-4 2 ACS/WFC ACCUM WFC-FIX F606W 2 none none none 1 557.0 S M-4 2 ACS/WFC ACCUM WFC-FIX F606W 3 none none none 1 557.0 S M-4 2 ACS/WFC ACCUM WFC-FIX F606W 4 none none none 1 557.0 S M-4 3 WFC3/IR MULTIAC IR-UVIS- F110W 1 none none none 2 N/A CUM FIX M-4 3 WFC3/IR MULTIAC IR-UVIS- F110W 2 none none none 2 N/A CUM FIX M-4 3 WFC3/IR MULTIAC IR-UVIS- F110W 3 none none none 2 N/A CUM FIX 12602( 3) - 08-Jul-2011 19:34:47 - [ 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 | ------------------------------------------------------------------------------------------------------------------------------------ M-4 3 WFC3/IR MULTIAC IR-UVIS- F110W 4 none none none 2 N/A CUM FIX M-4 4 ACS/WFC ACCUM WFC-FIX F606W 1 none none none 2 557.0 S M-4 4 ACS/WFC ACCUM WFC-FIX F606W 2 none none none 2 557.0 S M-4 4 ACS/WFC ACCUM WFC-FIX F606W 3 none none none 2 557.0 S M-4 4 ACS/WFC ACCUM WFC-FIX F606W 4 none none none 2 557.0 S M-4 5 WFC3/UVI ACCUM UVIS-IR- F390W 1 1 none none 3 911.0 S S FIX M-4 5 WFC3/UVI ACCUM UVIS-IR- F390W 1 2 none none 3 911.0 S S FIX M-4 5 WFC3/UVI ACCUM UVIS-IR- F390W 1 3 none none 3 911.0 S S FIX M-4 5 WFC3/UVI ACCUM UVIS-IR- F390W 2 1 none none 4 922.0 S S FIX M-4 5 WFC3/UVI ACCUM UVIS-IR- F390W 2 2 none none 4 922.0 S S FIX M-4 5 WFC3/UVI ACCUM UVIS-IR- F390W 2 3 none none 4 922.0 S S FIX M-4 6 ACS/WFC ACCUM WFC-FIX F814W 1 1 none none 3 860.0 S M-4 6 ACS/WFC ACCUM WFC-FIX F814W 1 2 none none 3 880.0 S M-4 6 ACS/WFC ACCUM WFC-FIX F814W 1 3 none none 3 780.0 S M-4 6 ACS/WFC ACCUM WFC-FIX F814W 2 1 none none 4 890.0 S M-4 6 ACS/WFC ACCUM WFC-FIX F814W 2 2 none none 4 890.0 S M-4 6 ACS/WFC ACCUM WFC-FIX F814W 2 3 none none 4 790.0 S 12602( 3) - 08-Jul-2011 19:34:47 - [ 7] Visit: 02 Visit Requirements: SAME ORIENT AS 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| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 M-4 WFC3/IR MULTIAC IR-UVIS-F F160W NSAMP=14, SAMP-SEQ=SPARS50 1 DEF PATTERN 1 1-2; PAR 2 CUM IX WITH 1 ------------------------------------------------------------------------------------------------------------------------------------ 2 M-4 ACS/WFC ACCUM WFC-FIX F814W 1 450 S see below ------------------------------------------------------------------------------------------------------------------------------------ 3 M-4 WFC3/IR MULTIAC IR-UVIS-F F160W NSAMP=14, SAMP-SEQ=SPARS50 1 DEF PATTERN 1 3-4; PAR 4 CUM IX WITH 3 ------------------------------------------------------------------------------------------------------------------------------------ 4 M-4 ACS/WFC ACCUM WFC-FIX F814W 1 450 S see below ------------------------------------------------------------------------------------------------------------------------------------ 5 M-4 WFC3/IR MULTIAC IR-UVIS-F F160W NSAMP=14, SAMP-SEQ=SPARS50 1 DEF PATTERN 1 5-6; PAR 6 CUM IX WITH 5 ------------------------------------------------------------------------------------------------------------------------------------ 6 M-4 ACS/WFC ACCUM WFC-FIX F814W 1 450 S see below ------------------------------------------------------------------------------------------------------------------------------------ 7 M-4 WFC3/IR MULTIAC IR-UVIS-F F160W NSAMP=14, SAMP-SEQ=SPARS50 1 DEF PATTERN 1 7-8; PAR 8 CUM IX WITH 7 ------------------------------------------------------------------------------------------------------------------------------------ 8 M-4 ACS/WFC ACCUM WFC-FIX F814W 1 450 S see below ------------------------------------------------------------------------------------------------------------------------------------ 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- F160W 1 none none none 1 N/A CUM FIX M-4 1 WFC3/IR MULTIAC IR-UVIS- F160W 2 none none none 1 N/A CUM FIX M-4 1 WFC3/IR MULTIAC IR-UVIS- F160W 3 none none none 1 N/A CUM FIX M-4 1 WFC3/IR MULTIAC IR-UVIS- F160W 4 none none none 1 N/A CUM FIX M-4 2 ACS/WFC ACCUM WFC-FIX F814W 1 none none none 1 475.0 S M-4 2 ACS/WFC ACCUM WFC-FIX F814W 2 none none none 1 557.0 S M-4 2 ACS/WFC ACCUM WFC-FIX F814W 3 none none none 1 557.0 S M-4 2 ACS/WFC ACCUM WFC-FIX F814W 4 none none none 1 557.0 S 12602( 3) - 08-Jul-2011 19:34:47 - [ 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 | ------------------------------------------------------------------------------------------------------------------------------------ M-4 3 WFC3/IR MULTIAC IR-UVIS- F160W 1 none none none 2 N/A CUM FIX M-4 3 WFC3/IR MULTIAC IR-UVIS- F160W 2 none none none 2 N/A CUM FIX M-4 3 WFC3/IR MULTIAC IR-UVIS- F160W 3 none none none 2 N/A CUM FIX M-4 3 WFC3/IR MULTIAC IR-UVIS- F160W 4 none none none 2 N/A CUM FIX M-4 4 ACS/WFC ACCUM WFC-FIX F814W 1 none none none 2 557.0 S M-4 4 ACS/WFC ACCUM WFC-FIX F814W 2 none none none 2 557.0 S M-4 4 ACS/WFC ACCUM WFC-FIX F814W 3 none none none 2 557.0 S M-4 4 ACS/WFC ACCUM WFC-FIX F814W 4 none none none 2 557.0 S M-4 5 WFC3/IR MULTIAC IR-UVIS- F160W 1 none none none 3 N/A CUM FIX M-4 5 WFC3/IR MULTIAC IR-UVIS- F160W 2 none none none 3 N/A CUM FIX M-4 5 WFC3/IR MULTIAC IR-UVIS- F160W 3 none none none 3 N/A CUM FIX M-4 5 WFC3/IR MULTIAC IR-UVIS- F160W 4 none none none 3 N/A CUM FIX M-4 6 ACS/WFC ACCUM WFC-FIX F814W 1 none none none 3 557.0 S M-4 6 ACS/WFC ACCUM WFC-FIX F814W 2 none none none 3 557.0 S M-4 6 ACS/WFC ACCUM WFC-FIX F814W 3 none none none 3 557.0 S M-4 6 ACS/WFC ACCUM WFC-FIX F814W 4 none none none 3 557.0 S M-4 7 WFC3/IR MULTIAC IR-UVIS- F160W 1 none none none 4 N/A CUM FIX M-4 7 WFC3/IR MULTIAC IR-UVIS- F160W 2 none none none 4 N/A CUM FIX M-4 7 WFC3/IR MULTIAC IR-UVIS- F160W 3 none none none 4 N/A CUM FIX M-4 7 WFC3/IR MULTIAC IR-UVIS- F160W 4 none none none 4 N/A CUM FIX M-4 8 ACS/WFC ACCUM WFC-FIX F814W 1 none none none 4 557.0 S M-4 8 ACS/WFC ACCUM WFC-FIX F814W 2 none none none 4 557.0 S M-4 8 ACS/WFC ACCUM WFC-FIX F814W 3 none none none 4 557.0 S M-4 8 ACS/WFC ACCUM WFC-FIX F814W 4 none none none 4 557.0 S 12602( 3) - 08-Jul-2011 19:34:47 - [ 9] Summary Form for Proposal 12602 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures IR-UVIS-FIX, UVIS-IR-FIX, WFC-FIX ------------------------------------------------------------------------------------------------------------------------------------ Configurations ACS/WFC, WFC3/IR, WFC3/UVIS ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM, MULTIACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters NSAMP=14, SAMP-SEQ=SPARS50 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ORIENT 290D TO 330 D, ORIENT 30D TO 65 D, PAR 2 WITH 1, PAR 4 WITH 3, PAR 6 WITH 5, PAR 8 WITH 7, PATTERN 1 1-2, PATTERN 1 3-4, PATTERN 1 5-6, PATTERN 1 7-8, PATTERN 2 5-6, SAME ORIENT AS 01 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F110W, F160W, F390W, F606W, F814W ------------------------------------------------------------------------------------------------------------------------------------ Target Names M-4 ------------------------------------------------------------------------------------------------------------------------------------