! Hubble Space Telescope Cycle 6 (1996) Phase II Proposal Template ! $Id: 6444,v 5.1 1996/04/16 19:14:12 pepsa Exp $ ! Hubble Space Telescope Cycle 6 (1996) Phase II Proposal Template ! $Id: 6444,v 5.1 1996/04/16 19:14:12 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: Landis ! Phone: 410-338-4560 , E-mail: landis@stsci.edu ! ! This partially completed template was generated from a Phase I proposal. ! Name of Phase I Proposal: archive-0156.smith.prop ! Date generated: Fri Dec 22 15:53:00 EST 1995 ! Proposal_Information ! Section 4 Title: Ultraviolet Imaging Polarimetry of the Low-Redshift BALQSO Mrk 231 Proposal_Category: GO Scientific_Category: GALAXIES & CLUSTERS Cycle: 6 Investigators PI_name: Paul Smith PI_Institution: University of Arizona CoI_Name: Gary Schmidt CoI_Institution: University of Arizona Contact: ! Y or N (designate at most one contact) CoI_Name: Dean Hines CoI_Institution: University of Arizona Contact: ! Y or N (designate at most one contact) Abstract: ! Free format text (please update) Markarian 231 is an extremely luminous galaxy with a peculiar Seyfert 1 nucleus that exhibits several absorption line systems, extremely powerful Fe II and infrared emission, and high optical and near-UV polarization. Scattering of nuclear light into our line of sight by dust distributed around the AGN produces the observed polarized flux. Several recent studies have established a strong link between Mrk 231 and broad absorption line quasars (BALQSOs). Its low redshift offers an opportunity to investigate the nuclear structure of a BALQSO-like object in more detail than is possible for the far more distant members of this class of AGN, and thereby test current BALQSO/normal QSO ``unification'' models. Direct imaging of the nucleus would be extremely difficult to interpret given the large amount of circumnuclear scattering. Therefore, we propose to obtain full polarization images of Mrk 231 in ultraviolet light to map the scattering regions within ~1 kpc of the nucleus. Individual scattering clouds can be expected to reach polarizations of >~50\ This, combined with the excellent spatial resolution of the FOC (~25 pc at the distance of Mrk 231), will allow for a detailed analysis of the inner regions of Mrk 231 and easily distinguish scattering clouds from unpolarized sources of nuclear ultraviolet flux. Our proposed observations have the potential to answer several fundamental questions concerning the nuclear structure of Mrk 231 (and by analogy, BALQSOs). Questions ! Free format text (please update) Observing_Description: We have chosen the FOC/96 over the Planetary Camera of WFPC2 because it achieves higher spatial resolution as well as having higher sensitivity in the ultraviolet. The 128*128 format of FOC samples the inner 1.5*1.5 kpc^2 of the object and allows a much higher linear counting rate than the standard 512*512 format. All images will be taken through the F346M filter to isolate the peak of the polarization spectrum as measured by the FOS (P ~ 15\ and avoid major emission lines. Two exposures of 2600 s each will be taken using the three polarizing prisms (POL0, POL60, and POL120). Each exposure plus FOC and HST overheads require 1 orbit, thus a polarization map of the nuclear region of Mrk 231 necessitates 6 orbits. Because the small FOC imaging format will be used, an interactive acquisition is required to center the nucleus in the 1arcs8*1arcs8 field of view. This acquisition will essentially take 1 orbit. The exposure time was calculated assuming that the flux measured in the 1arcs4*4arcs3 aperture of the FOS (sim4*10^-15 ergs cm^-2 s^- 1 Angstrom^-1; Smith et al. 1995) is uniformly distributed in the inner arcsec^2. Since the AGN is unresolved in ground- based observations, a large fraction of the flux must originate from this small region. The count rate in this region with the F346M+POLx combination is expected to be sim270 ct s^-1, or 0.068 ct s^-1 pix^-1 (the background is estimated to be sim9*10^-4 ct s^-1 pix^-1). In this case, there would be ~1400 cts from Mrk 231 (~20 background counts) in 5200 s per resolution element (roughly 2*2 pix^2). This yields an uncertainty based on Poisson statistics in the polarization of Sigma_P ~ 2\ per resolution element --- less than or comparable to the systematic uncertainties noted in the FOC Handbook and well below the levels of polarization expected to be present in the object. begintabularlll Cycle 6 & Primary Orbits:7 & Exposures:6, endtabular Real_Time_Justification: Centering of MRK231 into the 128x128 field of view requires an INTeractive ACQuisition. ! None. Calibration_Justification: ! Move appropriate text from Real_Time_Justification Additional_Comments: Fixed_Targets ! Section 5.1 Target_Number: 1 Target_Name: MRK231 Alternate_Names: UGC8058 Description: GALAXY,Seyfert Position: ! Most common specification format is RA=12H 56M 14.12S +/- 1.0", ! RA=0H 0M 0.00S +/- 0S, DEC=56D 52' 25.02" +/- 1.0", ! DEC=0D 0' 0.0" +/- 0", PLATE-ID=01R1 ! PLATE-ID=0000 Equinox: 2000 RV_or_Z: Z=0.041 RA_PM: ! Units are seconds of time per year Dec_PM: ! Units are seconds of arc per year Epoch: Annual_Parallax: Flux: F(5500) =12.0 +/- 1.0 E-15, ! Include at least V and B-V F(3000) = 3.0 +/- 0.5 E-15 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 ! DROP TO GYRO IF NECESSARY [NO REACQuisition] ! ORIENTation TO ! ORIENTation TO FROM ! ORIENTation TO FROM NOMINAL ! SAME ORIENTation AS ! CVZ ! PARallel ! SCHEDulability ! AFTER [BY [TO ]] ! AFTER ! BEFORE ! BETWEEN AND ! GROUP WITHIN