14695( 2) - 19-Jul-2016 16:17:46 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 14695 Version: 2 Check-in Time: 19-Jul-2016 16:17:46 STScI Edit Number: 0 Title WFC3 Imaging of 24 um Dropout Protostars in Orion ------------------------------------------------------------------------------------ Type Cycle GO 24 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. S Thomas Megeath University of Toledo Y CoI: Joseph Jon Booker University of Toledo N CoI: Amelia Marie Stutz Max-Planck-Institut fur Astronomie, N Heidelberg CoI: Dr. Elise Furlan California Institute of Technology N CoI: Marina A Kounkel University of Michigan N CoI: Dr. Thomas Stanke European Southern Observatory - Germany N CoI: Nicole Karnath University of Toledo N CoI: Dr. Will Fischer NASA Goddard Space Flight Center N ------------------------------------------------------------------------------------ Abstract We propose WFC3 imaging of four unusual candidate protostars that were uncovered in Spitzer and Herschel observations of the Orion Molecular Cloud. These sources exhibited a combination of weak 24 um fluxes, modest to bright 70 um fluxes, low luminosities and bolometric temperatures, but comparatively bright emission between 3.6 and 8 um. Since they did not fall into one of the typical protostar classes, they were not targeted for futher study. A recent HST/WFC3 F160W snapshot survey serendiptiously imaged one of these sources, revealing a bipolar nebula with a broad dust lane and binary point sources. This suggest that the lack of 24 um emission might be due to dust clearing in the inner disk and envelope by the binary. We propose to image the remaining four other sources with WFC3 in the F160W band, all of which have been detected in lower resolution, ground-based H-band observations and three of which show some sign of extension in the H or Ks-band. F160W imaging is essential to understand the geometry and inclination of the envelope and interpret the SEDs. These data will place these objects into the context of our picture of protostellar evolution, and test the possibility that these are envelopes being cleared by the gravitational torques from binary systems. ------------------------------------------------------------------------------------ Observations Description ------------------------ For each target we repeat the same observation in the F160W band. The observation consists of four separate dithers with Step 100 and 13 samples for a 600 second integration per exposure. A WFC3 line dither pattern with an angle of 41 degrees and a separation of 1.13 along the line is used to obtain sub-pixel sampling. The targets are identified from Spitzer coordinates. In two case, they have been shifted by about 20" to capture additional YSOs near the targets. ------------------------------------------------------------------------------------ 14695( 2) - 19-Jul-2016 16:17:46 - [ 2] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 037003 STAR, YSO RA=05H37M0.3500S, J2000 V = 25 DEC=-06D37'10.95" Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 2 092011 STAR, YSO RA=05H46M26.1700S, J2000 V = 25 DEC=-00D04'45.31" Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 3 038002 STAR, YSO RA=05H36M10.7900S, J2000 V = 25 DEC=-06D49'6.93" Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 4 302004 STAR, YSO RA=05H46M16.0000S, J2000 V = 25 DEC=+00D21'12.02" Reference Frame: ICRS ------------------------------------------------------------------------------------------------------------------------------------ 14695( 2) - 19-Jul-2016 16:17:46 - [ 3] Patterns ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 1 Primary_Pattern Secondary_Pattern Pattern_Type LINE Pattern_Purpose DITHER Number_Of_Points 4 Point_Spacing 1.13306 Line_Spacing Coordinate_Frame POS-TARG Pattern_Orient 41.788 Angle_Between_Sides Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ 14695( 2) - 19-Jul-2016 16:17:46 - [ 4] Visit: 01 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 037003 WFC3/IR MULTIAC IR F160W SAMP-SEQ=STEP100, NSAMP=12 1 DEF PATTERN 1 1 CUM (2396.929 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 | ------------------------------------------------------------------------------------------------------------------------------------ 037003 1 WFC3/IR MULTIAC IR F160W 1 none none none 1 N/A CUM 037003 1 WFC3/IR MULTIAC IR F160W 2 none none none 1 N/A CUM 037003 1 WFC3/IR MULTIAC IR F160W 3 none none none 1 N/A CUM 037003 1 WFC3/IR MULTIAC IR F160W 4 none none none 1 N/A CUM 14695( 2) - 19-Jul-2016 16:17:46 - [ 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 092011 WFC3/IR MULTIAC IR F160W SAMP-SEQ=STEP100, NSAMP=12 1 DEF PATTERN 1 1 CUM (2396.929 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 | ------------------------------------------------------------------------------------------------------------------------------------ 092011 1 WFC3/IR MULTIAC IR F160W 1 none none none 1 N/A CUM 092011 1 WFC3/IR MULTIAC IR F160W 2 none none none 1 N/A CUM 092011 1 WFC3/IR MULTIAC IR F160W 3 none none none 1 N/A CUM 092011 1 WFC3/IR MULTIAC IR F160W 4 none none none 1 N/A CUM 14695( 2) - 19-Jul-2016 16:17:46 - [ 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 038002 WFC3/IR MULTIAC IR F160W SAMP-SEQ=STEP100, NSAMP=12 1 DEF PATTERN 1 1 CUM (2396.929 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 | ------------------------------------------------------------------------------------------------------------------------------------ 038002 1 WFC3/IR MULTIAC IR F160W 1 none none none 1 N/A CUM 038002 1 WFC3/IR MULTIAC IR F160W 2 none none none 1 N/A CUM 038002 1 WFC3/IR MULTIAC IR F160W 3 none none none 1 N/A CUM 038002 1 WFC3/IR MULTIAC IR F160W 4 none none none 1 N/A CUM 14695( 2) - 19-Jul-2016 16:17:46 - [ 7] Visit: 04 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 302004 WFC3/IR MULTIAC IR F160W NSAMP=12, SAMP-SEQ=STEP100 1 DEF PATTERN 1 1 CUM (2396.929 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 | ------------------------------------------------------------------------------------------------------------------------------------ 302004 1 WFC3/IR MULTIAC IR F160W 1 none none none 1 N/A CUM 302004 1 WFC3/IR MULTIAC IR F160W 2 none none none 1 N/A CUM 302004 1 WFC3/IR MULTIAC IR F160W 3 none none none 1 N/A CUM 302004 1 WFC3/IR MULTIAC IR F160W 4 none none none 1 N/A CUM 14695( 2) - 19-Jul-2016 16:17:46 - [ 8] Summary Form for Proposal 14695 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures IR ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFC3/IR ------------------------------------------------------------------------------------------------------------------------------------ Opmodes MULTIACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters NSAMP=12, SAMP-SEQ=STEP100 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements PATTERN 1 1 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F160W ------------------------------------------------------------------------------------------------------------------------------------ Target Names 037003, 038002, 092011, 302004 ------------------------------------------------------------------------------------------------------------------------------------