! Proposal 5931, submission 1 ! PI: Dr. Klaus Meisenheimer ! Received Fri Mar 10 06:56:52 EST 1995 ! From: K.Meisenheimer@roe.ac.uk ! Hubble Space Telescope Cycle 5 (1995) Phase II Proposal Template ! $Id: 5931,v 5.1 1995/07/13 19:36:27 pepsa Exp $ ! ! Refer to the HST Phase II Proposal Instructions to fill this out ! ! Anything after a "!" is ignored, and may be deleted ! ! All keywords with multiple entries are comma delimited except the ! Visit_Requirements and Special_Requirements keywords which can be ! delimited with carriage returns or semi-colons, but not commas ! ! For help call your Program Coordinator: Ray Lucas ! Phone: 410 338-4716 , E-mail: lucas@stsci.edu ! ! This proposal is based on a template from a Phase I proposal. ! Date generated: Sat Dec 17 10:46:52 EST 1994 !---------------------------------------------------------------- ! PHASE II Proposal Version: Mar-09, 1995 Klaus Meisenheimer ! (implementing suggestions by: Ray Lucas) !---------------------------------------------------------------- Proposal_Information ! Section 4 Title: Location of Particle Acceleration in Radio Hot Spots. Proposal_Category: GO Scientific_Category: AGN Cycle: 5 Investigators PI_name: Dr. Klaus Meisenheimer PI_Institution: Max-Planck-Institut fuer Astronomie CoI_Name: Dr. Hermann-Josef Roeser CoI_Institution: Max-Planck-Institut fuer Astronomie Contact: Y CoI_Name: Dr. Richard A. Perley CoI_Institution: National Radio Astronomy Observatory Contact: ! Y or N (designate at most one contact) Abstract: ! Free format text (please update) A wide variety of AGN phenomena -- e.g. the powerful double radio sources, the superluminal jets in quasars, and last but not least the unexpected powerful Gamma -ray emission of many blazars -- cannot be explained without the presence of ultrarelativistic particles (electrons, protons and perhaps positrons). But it is still a mystery how the underlying cosmic particle accelerators work. Since the most efficient acceleration processes take place in hot spots of extended radio sources (reaching E_max > 10^5 m_ec^2) and these hot spots are relatively large (> 1 kpc) they are the prime target in order to study the acceleration process and its spatial structure in detail. For the nearest hot spots the required spatial resolution of 100 pc corresponds to about 0sec point 1 which is reached by the VLA at high radio frequencies and with the HST at optical frequencies. We propose to obtain high S/N images of the nearest two optically detected hot spots in 3C 111 and Pictor A in two bandpaths with WFPC2. They will allow us to derive maps of the radio-optical and optical spectral index with a resolution of 1/10 of the hot spot diameter. Such spectral index maps are the crucial observational input for the decision between competing models of the acceleration mechanisms and should lead to a quantitative description of the underlying physics. Questions ! Free format text (please update) Observing_Description: We propose to observe the western hot spot of Pictor A in 2 wavebands, seperated by a large wavelength ratio in order to derive an accurate optical spectral index alpha_opt. Optimum WFPC2 filters are F300W and F622W. We aim to reach a alpha_opt accuracy Sigma (Alpha ) <= 0.07 in order to detect the expected variations (DeltaAlpha_opt = 0.2 ... 0.7). This requires a S/N ratio of ~eq 30 (per resolution element, in the following: ``beam'') in each filter. From the optical spectrum we derive a total hot spot flux of 40 muJy (at 300 nm) and 125 muJy (at 620 nm), respectively. With an angular extend of 1sec point 2 * 0sec point 5 and using a circular beam of 0sec point 11 (FWHM) one gets a mean surface brightness of sigma_300 = 0.95 muJy/beam and sigma_620 = 2.98 MuJy/beam, respectively. In order to get a S/N ratio of 30 (per beam) in F300W we need 3 exposures a 1100 sec (calculated according SNR = N_obj / sqrtN_obj + N_sky + beam*RON^2 with \int QT from table 6.2). This would fill ~ 1.5 orbits. Thus we chose the integration time in F622W such that a 2-orbit visit is fully used: t_int = 3 * 350 sec. This results in a comfortable S/N ratio = 74 (per beam) which will allow us to study the morphology in great detail. ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ COMMENT on the ACTUAL PHASE II proposal: The dithering of the telescope pointing by 0.5" (11 PC pixel) or 1.0" (22 pix) currently causes a superfluous "telescope alignment overhead" of 2min. Therefore we had to reduce the integration times of our exposures to: 1100,1000 (orb-1) and 900,300,300,300 (orb-2). ---------------------------------------------------------------- For the eastern hot spot of 3C 111, we propose to obtain a high S/N map (>= 30) with one filter, F791W, only. With a total flux at 800 nm of 2.6 muJy and an extend of 0sec point 8 * 1sec point 5 we get a mean surface brightness of 0.15 muJy per 0.22arcsec beam (FWHM). This beam width is perfectly matched to the resolution of VLA maps at 3.6 cm which we are analysing currently. We calculate that 13 exposures a 2500 sec are sufficient to reach the attempted S/N ratio = 30. Thus 2 visits with in total 13 orbits are needed for this object. In fact, the experience with RPS2 showed that most one-orbit exposure can be extended to 2700S. for positional reference we included three exposures of 100s to get a unsaturated image of a nearby field star. Real_Time_Justification: Calibration_Justification: ! Move appropriate text from Real_Time_Justification Additional_Comments: Fixed_Targets ! Section 5.1 Target_Number: 1 Target_Name: PICTOR-A-WEST Alternate_Names: Description: GALAXY, Radio Galaxy, Hotspot Position: RA=05H 18M 00.05S +/-0.01S, DEC=-45.8146D +/- 0.0001D ! RA=0H 0M 0.00S +/- 0S, ! DEC=0D 0' 0.0" +/- 0", ! PLATE-ID=0000 Equinox: 1950 RV_or_Z: Z = 0.0350 RA_PM: 0 ! Units are seconds of time per year Dec_PM: 0 ! Units are seconds of arc per year Epoch: Annual_Parallax: 0 Flux: SURF-CONT(3000)= 2.8+/-0.3 E-16, SURF-CONT(6200)= 2.1+/-0.2 E-16 Comments: Target_Number: 2 Target_Name: 3C111-EAST Alternate_Names: Description: GALAXY, Radio Galaxy, Hotspot Position: RA=04H 15M 09.75S +/- 0.05S, DEC=+37D 55' 15.0" +/- 0.3" ! RA=0H 0M 0.00S +/- 0S, ! DEC=0D 0' 0.0" +/- 0", ! PLATE-ID=0000 Equinox: 1950 RV_or_Z: Z = 0.0485 RA_PM: 0 ! Units are seconds of time per year Dec_PM: 0 ! Units are seconds of arc per year Epoch: Annual_Parallax: 0 Flux: SURF-CONT(7900)= 1.3+/-0.3 E-18, SURF-CONT(6500)= 1.0+/-0.2 E-18 Comments: ! This is a template for a single visit containing a single exposure ! Repeat exposure and visit blocks as needed Visits ! Section 6 Visit_Number: 1 Visit_Requirements: ! Section 7.1 ! Uncomment or copy visit level special requirements needed ! Most of these requirements (including ORIENT) will limit scheduling ! PCS MODE [Fine | Gyro] ! GUIDing TOLerance ! ORIENTation TO ! ORIENTation TO FROM ! ORIENTation TO FROM NOMINAL ! SAME ORIENTation AS ! CVZ ! PARallel ! AFTER [BY [TO ]] ! AFTER ! BEFORE ! BETWEEN AND ! GROUP WITHIN