12261( 3) - 17-Nov-2010 13:34:33 - [ 1] HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 12261 Version: 3 Check-in Time: 17-Nov-2010 13:34:33 STScI Edit Number: 0 Title Resolving the Pictor A Jet ------------------------------------------------------------------------------------ Type Cycle GO 18 ------------------------------------------------------------------------------------ Investigators Contact? PI: Dr. Herman L. Marshall Massachusetts Institute of Technology CoI: Dr. Martin J. Hardcastle University of Hertfordshire N CoI: Dr. Eric S. Perlman Florida Institute of Technology N CoI: Dr. Diana M. Worrall University of Bristol N CoI: Dr. Mark Birkinshaw University of Bristol N CoI: Dr. Emil Lenc CSIRO, Australia Telescope National N Facility CoI: Dr. Daniel E. Harris Smithsonian Institution Astrophysical N Observatory CoI: Dr. Claudia Megan Urry Yale University N CoI: Dr. Aneta Siemiginowska Smithsonian Institution Astrophysical N Observatory ------------------------------------------------------------------------------------ Abstract We are proposing to obtain new images of the Pictor A jet in order to measure the spatial scale of clumping and to search for variability. X-ray images show a jet that has an opening angle of less than 1 degree that is about 2' (84 kpc, projected) long, unresolved for the first 30-40", and marginally detectable out to the terminal hotspot that is 4.2' from the core. The brightest portions of the inner jet are also marginally detectable in radio images. Based on a synchrotron model of the X-ray emission, we estimate that the bright parts of the inner jet should be detectable in the optical and IR in short HST observations with the WFC3. Three bandpasses will provide sufficient information on each knot to determine the synchrotron cutoffs, if it is in the optical band. ------------------------------------------------------------------------------------ Observations Description ------------------------ We plan to use two orbits of HST time using the WFC3. One orbit would be used for one filter (F160W) with the IR channel and the second orbit would be used for two filters of the UV channel: F475W and 814W. For the IR channel, filter F160W, a 3000 s exposure yields a 34$\sigma$ detection for the brightest part of the jet and 3.5$\sigma$ for point sources $\times 10$ fainter than the peak, even with our conservative flux estimates. Using the WFC3 UV channel exposure time calculator for filter F475W, we find a SNR of 19 for the peak of the jet in 1100 s and a similar SNR for filter 814W. Point sources $\times 8$ fainter than the peak will be detectable at 3$\sigma$ and again, our conservative estimates indicate that many of the jet knots and diffuse emission should be at least this bright. Real Time Justification ----------------------- 12261( 3) - 17-Nov-2010 13:34:33 - [ 2] Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ 12261( 3) - 17-Nov-2010 13:34:33 - [ 3] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 PICTOR-A-JET GALAXY, JET, KNOT, RA=05H19M44.6260S +/- 0.1", J2000 V = 18.8 +/- .1 Core is 19th magnitude. RADIO GALAXY DEC=-45D46'32.00" +/- 0.1" Knot fluxes in the range 50-1000 nJy at 1.6 microns, 0.2-4.0 microJy at 475 Angstroms Reference Frame: ICRS Comments: The pointing position is 1arcmin from the position of Pictor A along a position angle of -78.8deg, where 0deg is due north and positive is to the east. ------------------------------------------------------------------------------------------------------------------------------------ 12261( 3) - 17-Nov-2010 13:34:33 - [ 4] Patterns ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 3 Primary_Pattern Secondary_Pattern Pattern_Type WFC3-IR-DITHER-LINE-3PT Pattern_Purpose DITHER Number_Of_Points 3 Point_Spacing 0.605 Line_Spacing Coordinate_Frame POS-TARG Pattern_Orient 41.788 Angle_Between_Sides Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 5 Primary_Pattern Secondary_Pattern Pattern_Type WFC3-UVIS-DITHER-LINE-3PT Pattern_Purpose DITHER Number_Of_Points 3 Point_Spacing 0.135 Line_Spacing Coordinate_Frame POS-TARG Pattern_Orient 46.84 Angle_Between_Sides Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ 12261( 3) - 17-Nov-2010 13:34:33 - [ 5] Visit: 01 Visit Requirements: ORIENT 65D TO 120 D; ORIENT 0.0D TO 45 D; ORIENT 347D TO 359.9 D; ORIENT 150D TO 220 D; ORIENT 240D TO 310 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 PICTOR-A-JE WFC3/IR MULTIAC IR-UVIS-F F160W NSAMP=10, SAMP-SEQ=SPARS100 1 DEF PATTERN 3 1 T CUM IX ------------------------------------------------------------------------------------------------------------------------------------ 2 PICTOR-A-JE WFC3/UVI ACCUM UVIS-IR-F F475W 1 433 S PATTERN 5 2 T S IX ------------------------------------------------------------------------------------------------------------------------------------ 3 PICTOR-A-JE WFC3/UVI ACCUM UVIS-IR-F F814W 1 400 S PATTERN 5 3 T S IX ------------------------------------------------------------------------------------------------------------------------------------ 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 | ------------------------------------------------------------------------------------------------------------------------------------ PICTOR-A-JET 1 WFC3/IR MULTIAC IR-UVIS- F160W 1 none none none 1 N/A CUM FIX PICTOR-A-JET 1 WFC3/IR MULTIAC IR-UVIS- F160W 2 none none none 1 N/A CUM FIX PICTOR-A-JET 1 WFC3/IR MULTIAC IR-UVIS- F160W 3 none none none 1 N/A CUM FIX PICTOR-A-JET 2 WFC3/UVI ACCUM UVIS-IR- F475W 1 none none none 2 N/A S FIX PICTOR-A-JET 2 WFC3/UVI ACCUM UVIS-IR- F475W 2 none none none 2 N/A S FIX PICTOR-A-JET 2 WFC3/UVI ACCUM UVIS-IR- F475W 3 none none none 2 N/A S FIX PICTOR-A-JET 3 WFC3/UVI ACCUM UVIS-IR- F814W 1 none none none 2 N/A S FIX PICTOR-A-JET 3 WFC3/UVI ACCUM UVIS-IR- F814W 2 none none none 2 N/A S FIX PICTOR-A-JET 3 WFC3/UVI ACCUM UVIS-IR- F814W 3 none none none 2 N/A S FIX 12261( 3) - 17-Nov-2010 13:34:33 - [ 6] Summary Form for Proposal 12261 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures IR-UVIS-FIX, UVIS-IR-FIX ------------------------------------------------------------------------------------------------------------------------------------ Configurations WFC3/IR, WFC3/UVIS ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM, MULTIACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters NSAMP=10, SAMP-SEQ=SPARS100 ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ORIENT 0.0D TO 45 D, ORIENT 150D TO 220 D, ORIENT 240D TO 310 D, ORIENT 347D TO 359.9 D, ORIENT 65D TO 120 D, PATTERN 3 1, PATTERN 5 2, PATTERN 5 3 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F160W, F475W, F814W ------------------------------------------------------------------------------------------------------------------------------------ Target Names PICTOR-A-JET ------------------------------------------------------------------------------------------------------------------------------------