14709( 4) - 22-Jul-2016 11:03:30 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 14709 Version: 4 Check-in Time: 22-Jul-2016 11:03:30 STScI Edit Number: 2 Title HST/WFC3 Spectroscopy of < 400 AU Companions to Orion Young Stellar Objects ------------------------------------------------------------------------------------ Type Cycle GO 24 ------------------------------------------------------------------------------------ Investigators Contact? PI: Brian Mazur University of Toledo Y CoI: Dr. Elise Furlan California Institute of Technology N CoI: Dr. Lee W. Hartmann University of Michigan N CoI: Dr. Will Fischer NASA Goddard Space Flight Center N CoI: Marina A Kounkel University of Michigan N CoI: Dr. S Thomas Megeath University of Toledo N ------------------------------------------------------------------------------------ Abstract We propose WFC3 G141 grism spectroscopy of companions to young stellar objects (YSOs) in the Orion molecular cloud which were identified in a WFC3/HST 1.6 micron survey of 320 YSOs in Orion. We will target six close companions with separaitons < 400 AU which have F160W magnitudes between 17-19; these are too faint obtain spectra from ground-based telecopes using LGS AO. To determine spectral types and masses for these sources, we will use grism spectroscopy to detect broad water features in the photospheric spectrum. These observations are part of a coordinated spectroscopy campaign; the remaining companions have been/will be observed using spectrographs on ground-based telescopes as well as a HST (Cycle 22). These data will constrain the companion mass function at projected separations of 100-1000 AU from Orion young stellar objects. Given their faint magnitudes, as many as half of the companions may be below the Hydrogen burning limit. With spectra, we can determine whether or not there is an excess of sub-stellar companions relative to the field IMF at these separations; thereby testing whether the companions form from the fragmentation of the parental cloud or by fragmenation in protostellar disks. Furthermore, the HST survey showed that the observed fraction of stars with companions increases ~50% between low and high stellar density region in Orion; suggesting that the formation of multiple systems is dependent on the birth environment. With spectra, we can explore the physical mechanisms for this enhanced formation. ------------------------------------------------------------------------------------ Observations Description ------------------------ G141 Grism Spectroscopy ------------------------------------------------------------------------------------ 14709( 4) - 22-Jul-2016 11:03:30 - [ 2] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 3 HOPS115 STAR, YSO RA=05H39M56.5243S, J2000 V = 35 F160W = 17.8 DEC=-07D25'51.58" Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 4 HOPS138 STAR, YSO RA=05H38M48.3200S, J2000 V = 35 F160W = 20 DEC=-07D02'43.70" Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 5 HOPS281 STAR, YSO RA=05H40M24.6226S, J2000 V = 35 F160W = 17.3 DEC=-07D43'8.07" Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 6 HOPS24 STAR, YSO RA=05H34M46.9294S, J2000 V = 35 F160W = 17.3 DEC=-05D44'51.15" Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 1 HOPS189 STAR, YSO RA=05H35M30.9089S, J2000 V = 35 F160W = 16.7 DEC=-06D26'31.99" Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 2 HOPS79 STAR, YSO RA=05H35M27.8330S, J2000 V = 35 F160W = 18.8 DEC=-05D05'36.28" Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 14709( 4) - 22-Jul-2016 11:03:30 - [ 3] Patterns ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 1 Primary_Pattern Secondary_Pattern Pattern_Type LINE Pattern_Purpose DITHER Number_Of_Points 2 Point_Spacing 3.604 Line_Spacing Coordinate_Frame POS-TARG Pattern_Orient 82.75 Angle_Between_Sides Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ 14709( 4) - 22-Jul-2016 11:03:30 - [ 4] Visit: 01 Visit Requirements: ORIENT 239D TO 239 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 HOPS115 WFC3/IR MULTIAC GRISM1024 F160W NSAMP=9, SAMP-SEQ=STEP25 1 DEF PATTERN 1 1-2 CUM (248.464 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 HOPS115 WFC3/IR MULTIAC GRISM1024 G141 NSAMP=13, SAMP-SEQ=STEP200 1 DEF CUM (2398.463 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 | ------------------------------------------------------------------------------------------------------------------------------------ HOPS115 1 WFC3/IR MULTIAC GRISM102 F160W 1 none none none 1 N/A CUM 4 HOPS115 1 WFC3/IR MULTIAC GRISM102 F160W 2 none none none 1 N/A CUM 4 HOPS115 2 WFC3/IR MULTIAC GRISM102 G141 1 none none none 1 N/A CUM 4 HOPS115 2 WFC3/IR MULTIAC GRISM102 G141 2 none none none 1 N/A CUM 4 14709( 4) - 22-Jul-2016 11:03:30 - [ 5] Visit: 02 Visit Requirements: ORIENT 45D TO 45 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 HOPS138 WFC3/IR MULTIAC GRISM1024 F160W NSAMP=9, SAMP-SEQ=STEP25 1 DEF GS ACQ SCENARIO ONEB1B3; CUM (248.464 PATTERN 1 1-2 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 HOPS138 WFC3/IR MULTIAC GRISM1024 G141 NSAMP=13, SAMP-SEQ=STEP200 1 DEF CUM (2398.463 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 | ------------------------------------------------------------------------------------------------------------------------------------ HOPS138 1 WFC3/IR MULTIAC GRISM102 F160W 1 none none none 1 N/A CUM 4 HOPS138 1 WFC3/IR MULTIAC GRISM102 F160W 2 none none none 1 N/A CUM 4 HOPS138 2 WFC3/IR MULTIAC GRISM102 G141 1 none none none 1 N/A CUM 4 HOPS138 2 WFC3/IR MULTIAC GRISM102 G141 2 none none none 1 N/A CUM 4 14709( 4) - 22-Jul-2016 11:03:30 - [ 6] Visit: 03 Visit Requirements: ORIENT 27.5D TO 27.5 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 HOPS281 WFC3/IR MULTIAC GRISM1024 F160W NSAMP=9, SAMP-SEQ=STEP25 1 DEF GS ACQ SCENARIO ONEB1B3; CUM (248.464 PATTERN 1 1-2 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 HOPS281 WFC3/IR MULTIAC GRISM1024 G141 NSAMP=13, SAMP-SEQ=STEP200 1 DEF CUM (2398.463 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 | ------------------------------------------------------------------------------------------------------------------------------------ HOPS281 1 WFC3/IR MULTIAC GRISM102 F160W 1 none none none 1 N/A CUM 4 HOPS281 1 WFC3/IR MULTIAC GRISM102 F160W 2 none none none 1 N/A CUM 4 HOPS281 2 WFC3/IR MULTIAC GRISM102 G141 1 none none none 1 N/A CUM 4 HOPS281 2 WFC3/IR MULTIAC GRISM102 G141 2 none none none 1 N/A CUM 4 14709( 4) - 22-Jul-2016 11:03:30 - [ 7] Visit: 04 Visit Requirements: ORIENT 344.5D TO 344.5 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 HOPS24 WFC3/IR MULTIAC GRISM1024 F160W NSAMP=9, SAMP-SEQ=STEP25 1 DEF GS ACQ SCENARIO ONEB1B3; CUM (248.464 PATTERN 1 1-2 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 HOPS24 WFC3/IR MULTIAC GRISM1024 G141 NSAMP=13, SAMP-SEQ=STEP200 1 DEF CUM (2398.463 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 | ------------------------------------------------------------------------------------------------------------------------------------ HOPS24 1 WFC3/IR MULTIAC GRISM102 F160W 1 none none none 1 N/A CUM 4 HOPS24 1 WFC3/IR MULTIAC GRISM102 F160W 2 none none none 1 N/A CUM 4 HOPS24 2 WFC3/IR MULTIAC GRISM102 G141 1 none none none 1 N/A CUM 4 HOPS24 2 WFC3/IR MULTIAC GRISM102 G141 2 none none none 1 N/A CUM 4 14709( 4) - 22-Jul-2016 11:03:30 - [ 8] Visit: 05 Visit Requirements: ORIENT 314D TO 314 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 HOPS189 WFC3/IR MULTIAC GRISM1024 F160W NSAMP=9, SAMP-SEQ=STEP25 1 DEF GS ACQ SCENARIO BASE1B3; CUM (248.464 PATTERN 1 1-2 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 HOPS189 WFC3/IR MULTIAC GRISM1024 G141 NSAMP=13, SAMP-SEQ=STEP200 1 DEF CUM (2398.463 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 | ------------------------------------------------------------------------------------------------------------------------------------ HOPS189 1 WFC3/IR MULTIAC GRISM102 F160W 1 none none none 1 N/A CUM 4 HOPS189 1 WFC3/IR MULTIAC GRISM102 F160W 2 none none none 1 N/A CUM 4 HOPS189 2 WFC3/IR MULTIAC GRISM102 G141 1 none none none 1 N/A CUM 4 HOPS189 2 WFC3/IR MULTIAC GRISM102 G141 2 none none none 1 N/A CUM 4 14709( 4) - 22-Jul-2016 11:03:30 - [ 9] Visit: 06 Visit Requirements: ORIENT 45D TO 50 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 HOPS79 WFC3/IR MULTIAC GRISM1024 F160W NSAMP=9, SAMP-SEQ=STEP25 1 DEF GS ACQ SCENARIO BASE1B3; CUM (248.464 PATTERN 1 1-2 S) ------------------------------------------------------------------------------------------------------------------------------------ 2 HOPS79 WFC3/IR MULTIAC GRISM1024 G141 NSAMP=13, SAMP-SEQ=STEP200 1 DEF CUM (2398.463 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 | ------------------------------------------------------------------------------------------------------------------------------------ HOPS79 1 WFC3/IR MULTIAC GRISM102 F160W 1 none none none 1 N/A CUM 4 HOPS79 1 WFC3/IR MULTIAC GRISM102 F160W 2 none none none 1 N/A CUM 4 HOPS79 2 WFC3/IR MULTIAC GRISM102 G141 1 none none none 1 N/A CUM 4 HOPS79 2 WFC3/IR MULTIAC GRISM102 G141 2 none none none 1 N/A CUM 4 14709( 4) - 22-Jul-2016 11:03:30 - [ 10] Summary Form for Proposal 14709 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures GRISM1024 ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFC3/IR ------------------------------------------------------------------------------------------------------------------------------------ Opmodes MULTIACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters NSAMP=13, NSAMP=9, SAMP-SEQ=STEP200, SAMP-SEQ=STEP25 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements GS ACQ SCENARIO BASE1B3, GS ACQ SCENARIO ONEB1B3, ORIENT 239D TO 239 D, ORIENT 27.5D TO 27.5 D, ORIENT 314D TO 314 D, ORIENT 344.5D TO 344.5 D, ORIENT 45D TO 45 D, ORIENT 45D TO 50 D, PATTERN 1 1-2 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F160W, G141 ------------------------------------------------------------------------------------------------------------------------------------ Target Names HOPS115, HOPS138, HOPS189, HOPS24, HOPS281, HOPS79 ------------------------------------------------------------------------------------------------------------------------------------