9847( 6) - 07/01/03 16:39 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 9847 Version: 6 Check-in Date: 01-Jul-2003 16:36:09 1.Proposal Title: The Structure and Physics of Extragalactic Jets ------------------------------------------------------------------------------------ 2. Proposal For 3. Cycle GO 12 ------------------------------------------------------------------------------------ 4. Investigators Contact? PI: Dr. Eric S. Perlman University of Maryland Baltimore County CoI: Dr. Alessandro Capetti Osservatorio Astronomico di Torino N CoI: Dr. John A. Biretta Space Telescope Science Institute N CoI: Dr. William B. Sparks Space Telescope Science Institute N CoI: Dr. Sebastian Jester Fermilab N CoI: Dr. Christopher P. ODea Space Telescope Science Institute N CoI: Dr. Stefi A. Baum Space Telescope Science Institute N CoI: Dr. J. Patrick Leahy University of Manchester N CoI: Dr. Mark Birkinshaw University of Bristol N CoI: Dr. Diana M. Worrall University of Bristol N CoI: Dr. F. Duccio Macchetto Space Telescope Science Institute N CoI: Dr. Andre' Martel The Johns Hopkins University N ------------------------------------------------------------------------------------ 5. Abstract As part of an ongoing investigation into the physics of jets, we propose to obtain ACS polarimetry of the jets of 3C 15, 3C 66B, 3C 346, 3C 371 and PKS 0521-36. This builds on our earlier HST work and completes a sample of 9 jets that spans the range of jet luminosities and morphological types. All of these jets have deep, multi-band HST imaging, and radio polarimetry at matching resolution, and all but one has Chandra data. Our goal is to investigate three fundamental issues, brought to light by recent HST and Chandra observations. These are: (1) What is the energetic and magnetic field structure of jets? (2) What is the nature of particle acceleration in jets? (3) What is the nature of the X-ray emission from jets, and what is its relationship to lower energy emissions? Optical polarimetry provides unique information about all of these issues. Because of their vastly different radiative lifetimes (hundreds of years compared to millions), optical and radio polarimetry probe different electron populations and emission regions. Comparison of radio and optical polarimetry can therefore yield direct information about the three- dimensional energetic and magnetic field structure of jets. Optical polarimetry traces the magnetic field configuration in and near electron acceleration regions, and when combined with optical and X-ray spectral index maps, polarimetry can yield key constraints about particle acceleration and the nature of the X-ray emission of jets. ------------------------------------------------------------------------------------ 9847( 6) - 07/01/03 16:39 - [ 2] Observations Description ------------------------ We propose to obtain polarimetry of five jets, 3C 15, 3C 66B, 3C 346, 3C 371 and PKS 0521-36, to complete HST polarimetry of a sample of 9 optical jets. This sample was chosen to span the range of observed jet luminosities and morphologies in known objects and represents the highest surface brightness optical jets currently known. We have chosen to observe each of these with ACS+WFC+POLVIS+F606W. While WFPC2 also has polarimetric capability, ACS is greatly superior both in terms of the characteristics of its polarizers, and more importantly in its higher sensitivity. Thus ACS is the instrument of choice. We have chosen the F606W filter to give us the best compromise between total count rate, jet-to-galaxy ratio, and polarizer fidelity. This is critically important because we will need to do the highest quality galaxy subtraction possible prior to combining the three polarizer observations to obtain Stokes I, Q and U images. We will do sub-pixel dithering and combine the images with tasks in the IRAF dither package. This technique is well tested, and will allow us to achieve the full ~ 0.05'' resolution which HST is capable of at 6000 Angstroms. In order to achieve maximum observing efficiency, we will not CR-SPLIT at each dither position. Instead we will rely on the multiple dither positions to subtract out both cosmic rays and hot pixels. This is a strategy recommended in the latest ACS STAN; we have used this strategy successfully in previous WFPC2 observations. According to the ACS Exposure Time Calculator, a 2040s (1 orbit) observation will yield S/N=30 for R=20 mag/arcsec^2, using the WFC+POLVIS+F606W combination (i.e., POL0V+F606W, POL60V+F606W, POL120V+F606W). We have verified the reasonability of this calculation by using our own data for 3C 264 (GO-9493, with ACS/HRC) and M87 (GO/DD-9705, with ACS/HRC). This very high S/N is absolutely necessary to yield good discrimination between different structural features, as it will yield errors of 3% in polarized flux and errors ~6 degrees in PA. By comparison, these jets have polarizations of ~20-30% in the radio, and (if they follow the pattern of M87, 3C 78 and 3C 273) they should be at least equally polarized in the optical. It is not critical that the optical polarimetry proposed here will be separated by a few years from the radio observations to which they will be compared. This is because the relevant radiative lifetimes are hundreds of years, so unless extremely fast superluminal motions are present in these jets (upwards of 10c - not seen in these objects on arcsecond scales), morphological changes are not a strong concern. We have included observations of two jets (PKS 0521-36 and 3C 371) without the POLVIS filters. This will help us calibrate out the effects of the ACS's large instrumental polarization. Two sources (but not more) need to be observed this way because of the need to derive any dependence on ORIENT. Real Time Justification ----------------------- Calibration Justification ------------------------- Additional Comments ------------------- 9847( 6) - 07/01/03 16:39 - [ 3] ------------------------------------------------------------------------------------ 9847( 6) - 07/01/03 16:39 - [ 4] TARGET LIST Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 3C66B GALAXY, JET RA=02H23M11.4S +/- 0.1", J2000 V = 14.0 DEC=+42D59'31.0" +/- 0.1" Coordinate Source: GUIDE_STAR_CATALOG 2 3C371 GALAXY, JET RA=18H06M50.6S +/- 0.1", J2000 V = 14.0 DEC=+69D49'28.0" +/- 0.1" Coordinate Source: GUIDE_STAR_CATALOG 3 3C346 GALAXY, JET RA=16H43M48.6S +/- 0.1", J2000 V = 18.0 DEC=+17D15'49.0" +/- 0.1" Coordinate Source: GUIDE_STAR_CATALOG 4 PKS0521-36 GALAXY, JET RA=05H23M2.0S +/- 0.1", DEC=- J2000 V = 16.0 36D26'42.0" +/- 0.1" Coordinate Source: GUIDE_STAR_CATALOG 5 3C15 GALAXY, JET RA=00H37M4.1S +/- 0.1", DEC=- J2000 V = 16.0 01D09'8.0" +/- 0.1" Coordinate Source: GUIDE_STAR_CATALOG 9847( 6) - 07/01/03 16:39 - [ 5] Patterns ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 1 Primary_Pattern Secondary_Pattern Pattern_Type ACS-WFC-DITHER-LINE Pattern_Purpose DITHER Number_Of_Points 2 Point_Spacing 0.183 Coordinate_Frame POS-TARG Pattern_Orient 47.17 Center_Pattern YES ------------------------------------------------------------------------------------------------------------------------------------ Pattern_Number: 2 Primary_Pattern Secondary_Pattern Pattern_Type ACS-WFC-DITHER-BOX Pattern_Purpose DITHER Number_Of_Points 4 Point_Spacing 0.265 Coordinate_Frame POS-TARG Pattern_Orient 20.67 Center_Pattern NO ------------------------------------------------------------------------------------------------------------------------------------ 9847( 6) - 07/01/03 16:39 - [ 6] Visit: 11 Visit Priority: Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 3C346 ACS/WF ACCUM WFC F606W, CR-SPLIT=NO 1 251 S PATTERN 1 1 C POL0V ------------------------------------------------------------------------------------------------------------------------------------ 2 3C346 ACS/WF ACCUM WFC F606W, CR-SPLIT=NO 1 251 S PATTERN 1 2 C POL60V ------------------------------------------------------------------------------------------------------------------------------------ 3 3C346 ACS/WF ACCUM WFC F606W, CR-SPLIT=NO 1 251 S PATTERN 1 3 C POL120V ------------------------------------------------------------------------------------------------------------------------------------ 9847( 6) - 07/01/03 16:39 - [ 7] Visit: 12 Visit Priority: Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 PKS0521-36 ACS/WF ACCUM WFC F606W, CR-SPLIT=NO 1 580 S PATTERN 1 1 C POL0V ------------------------------------------------------------------------------------------------------------------------------------ 2 PKS0521-36 ACS/WF ACCUM WFC1-2K F606W CR-SPLIT=NO 1 160 S POS TARG 0, 0 C ------------------------------------------------------------------------------------------------------------------------------------ 3 PKS0521-36 ACS/WF ACCUM WFC F606W, CR-SPLIT=NO 1 580 S PATTERN 1 3 C POL60V ------------------------------------------------------------------------------------------------------------------------------------ 4 PKS0521-36 ACS/WF ACCUM WFC F606W, CR-SPLIT=NO 1 580 S PATTERN 1 4 C POL120V ------------------------------------------------------------------------------------------------------------------------------------ 5 PKS0521-36 ACS/WF ACCUM WFC1-2K F606W CR-SPLIT=NO 1 300 S POS TARG 0.124, 0.134 C ------------------------------------------------------------------------------------------------------------------------------------ 9847( 6) - 07/01/03 16:39 - [ 8] Visit: 13 Visit Priority: Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 3C66B ACS/WF ACCUM WFC F606W, CR-SPLIT=NO 1 742 S PATTERN 2 1 C POL0V ------------------------------------------------------------------------------------------------------------------------------------ 2 3C66B ACS/WF ACCUM WFC F606W, CR-SPLIT=NO 1 742 S PATTERN 2 2 C POL60V ------------------------------------------------------------------------------------------------------------------------------------ 3 3C66B ACS/WF ACCUM WFC F606W, CR-SPLIT=NO 1 742 S PATTERN 2 3 C POL120V ------------------------------------------------------------------------------------------------------------------------------------ 9847( 6) - 07/01/03 16:39 - [ 9] Visit: 14 Visit Priority: Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 3C371 ACS/WF ACCUM WFC1-2K F606W CR-SPLIT=NO 1 76 S POS TARG 0, 0 C ------------------------------------------------------------------------------------------------------------------------------------ 2 3C371 ACS/WF ACCUM WFC F606W, CR-SPLIT=NO 1 707 S PATTERN 2 2 C POL0V ------------------------------------------------------------------------------------------------------------------------------------ 3 3C371 ACS/WF ACCUM WFC1-2K F606W CR-SPLIT=NO 1 176 S POS TARG 0.124, 0.134 C ------------------------------------------------------------------------------------------------------------------------------------ 4 3C371 ACS/WF ACCUM WFC F606W, CR-SPLIT=NO 1 707 S PATTERN 2 4 C POL60V ------------------------------------------------------------------------------------------------------------------------------------ 5 3C371 ACS/WF ACCUM WFC1-2K F606W CR-SPLIT=NO 1 176 S SAME POS AS 3 C ------------------------------------------------------------------------------------------------------------------------------------ 6 3C371 ACS/WF ACCUM WFC F606W, CR-SPLIT=NO 1 707 S PATTERN 2 6 C POL120V ------------------------------------------------------------------------------------------------------------------------------------ 7 3C371 ACS/WF ACCUM WFC1-2K F606W CR-SPLIT=NO 1 230 S SAME POS AS 1 C ------------------------------------------------------------------------------------------------------------------------------------ 9847( 6) - 07/01/03 16:39 - [ 10] Visit: 15 Visit Priority: Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1 3C15 ACS/WF ACCUM WFC F606W, CR-SPLIT=NO 1 718 S PATTERN 2 1 C POL0V ------------------------------------------------------------------------------------------------------------------------------------ 2 3C15 ACS/WF ACCUM WFC F606W, CR-SPLIT=NO 1 718 S PATTERN 2 2 C POL60V ------------------------------------------------------------------------------------------------------------------------------------ 3 3C15 ACS/WF ACCUM WFC F606W, CR-SPLIT=NO 1 718 S PATTERN 2 3 C POL120V ------------------------------------------------------------------------------------------------------------------------------------ 9847( 6) - 07/01/03 16:39 - [ 11] Summary Form for Proposal 9847 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures WFC WFC1-2K ------------------------------------------------------------------------------------------------------------------------------------ Configurations ACS/WFC ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters CR-SPLIT=NO ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements PATTERN 1 1 PATTERN 1 2 PATTERN 1 3 POS TARG 0, 0 PATTERN 1 4 POS TARG 0.124, 0.134 PATTERN 2 1 PATTERN 2 2 PATTERN 2 3 PATTERN 2 4 SAME POS AS 3 PATTERN 2 6 SAME POS AS 1 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements F606W,POL0V F606W,POL60V F606W,POL120V F606W ------------------------------------------------------------------------------------------------------------------------------------ Target Names 3C346 PKS0521-36 3C66B 3C371 3C15 ------------------------------------------------------------------------------------------------------------------------------------