! Proposal 5939, submission 1 ! PI: C. Megan Urry ! Received Fri Feb 24 14:11:35 EST 1995 ! From: pesce@stsci.edu ! Hubble Space Telescope Cycle 5 (1995) Phase II Proposal Template ! $Id: 5939,v 7.1 1996/03/14 18:53:23 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 partially completed template was generated from a Phase I proposal. ! Date generated: Sat Dec 17 10:56:01 EST 1994 ! Proposal_Information ! Section 4 Title: Evolution in the Isotropic Properties of BL Lac Objects Proposal_Category: GO Scientific_Category: AGN Cycle: 5 Investigators PI_name: C. Megan Urry PI_Institution: Space Telescope Science Institute CoI_Name: Joseph E. Pesce CoI_Institution: Space Telescope Science Institute Contact: Y ! Y or N (designate at most one contact) CoI_Name: Renato Falomo CoI_Institution: Osservatorio Astronomico di Padova Contact: ! Y or N (designate at most one contact) CoI_Name: Mauro Giavalisco CoI_Institution: Space Telescope Science Institute Contact: ! Y or N (designate at most one contact) CoI_Name: Rita M. Sambruna CoI_Institution: Space Telescope Science Institute Contact: ! Y or N (designate at most one contact) CoI_Name: Riccardo Scarpa CoI_Institution: Osservatorio Astronomico di Padova Contact: ! Y or N (designate at most one contact) CoI_Name: Aldo Treves CoI_Institution: SISSA/ISAS Contact: ! Y or N (designate at most one contact) Abstract: ! Free format text (please update) Although high quality imaging of a few local BL Lac objects shows they are in giant elliptical galaxies, nothing is known about host galaxies at higher redshifts. Similarly, nearby BL Lac objects appear to be in rich clusters of galaxies but little is known about the evolution of these environments. Some nearby BL Lacs have close companions (r~<2''), possibly indicating that interactions are important the BL Lac phenomenon. There is disagreement about whether local z<0.3 and distant (z>0.5) BL Lac objects are the same thing or the latter are more closely related to quasars. The host galaxies and environments of local objects support the idea that BL Lacs are aligned versions of low-luminosity (FRI) radio galaxies, the so-called ``unified scheme,'' but as FRIs are only observed locally the extension of this scheme to higher redshift is unclear. We propose to study the host galaxies and environments of four radio-selected BL Lac objects from a well-defined, complete sample at high redshift (0.5 < z < 1), to measure evolution in the isotropic properties of BL Lac objects and to determine whether the low- and high-redshift BL Lacs are similar or are distinct classes. No comparable HST data exist or are planned for any BL Lac objects. Questions ! Free format text (please update) Observing_Description: We propose WFPC2 images in one filter, F814w (which corresponds approximately to V at the median sample redshift). We will obtain several short exposures to get the central point source without saturating the detector, and several medium and long ones to get the galaxy fuzz. The medium exposure is calculated to, at most (depending on the variability of the point source), saturate the central pixel. The longer exposure should, at most, cause the first pixel to bleed. We will rotate the telescope between sets of exposures (short, medium, long, roll, short, medium, long. It is imperative that for each target the 2 visits are in consecutive orbits. The point source will be centered in the PC to get the best resolution in the inner part of the galaxy; the WF chips will give the environments (0.5-0.6 Mpc projected distance from the BL Lac object). Our integration times should be more than sufficient to get a S/N ratio of 3 at the 24 mag/arcsec^2 isophote, which is sufficient to determine the host galaxy properties. The filter chosen is frequently used; no special calibration exposures are required but PSF monitoring in this filter would greatly enhance our program. Real_Time_Justification: We have no special scheduling requirements. Calibration_Justification: ! Move appropriate text from Real_Time_Justification We have no special calibration requirments. PSF monitoring in the PC with the F814W filter would help us better subtract the nuclear point source, which is expected to be the limiting factor in detecting the host galaxy. Additional_Comments: We require the spacecraft to roll between sets of observations (one set of short exposure, medium exposure, and long exposure per orbit). It is imperative that for each target the two visits are sequential, in consecutive orbits with nothing intervening but the roll. Fixed_Targets ! Section 5.1 Target_Number: 1 Target_Name: QSO0828+493 Alternate_Names: Description:GALAXY,BL Lac Position: RA=08H 32M 23.2S +/- 0.5S, DEC=+49D 13' 21.0" +/- 0.5" ! Most common specification format is ! RA=0H 0M 0.00S +/- 0S, ! DEC=0D 0' 0.0" +/- 0", ! PLATE-ID=0000 Equinox: J2000 RV_or_Z: Z = 0.548 RA_PM: ! Units are seconds of time per year Dec_PM: ! Units are seconds of arc per year Epoch: Annual_Parallax: Flux: V=18.5 +/- 1.0 ! Include at least V and B-V Comments: Fixed_Targets ! Section 5.1 Target_Number: 2 Target_Name: PKS1538+149 Alternate_Names: Description: GALAXY,BL Lac Position: RA=15H 40M 49.5S +/- 0.5S, DEC=+14D 47' 45.9" +/- 0.5" ! Most common specification format is ! RA=0H 0M 0.00S +/- 0S, ! DEC=0D 0' 0.0" +/- 0", ! PLATE-ID=0000 Equinox: J2000 RV_or_Z: Z = 0.605 RA_PM: ! Units are seconds of time per year Dec_PM: ! Units are seconds of arc per year Epoch: Annual_Parallax: Flux: V=17.1 +/- 1.3 ! Include at least V and B-V Comments: Fixed_Targets ! Section 5.1 Target_Number: 3 Target_Name: QSO1823+568 Alternate_Names: Description: GALAXY,BL Lac Position: RA=18H 24M 07.1S +/- 0.5S, DEC=+56D 51' 01.5" +/- 0.5" ! Most common specification format is ! RA=0H 0M 0.00S +/- 0S, ! DEC=0D 0' 0.0" +/- 0", ! PLATE-ID=0000 Equinox: J2000 RV_or_Z: Z = 0.664 RA_PM: ! Units are seconds of time per year Dec_PM: ! Units are seconds of arc per year Epoch: Annual_Parallax: Flux: V=18.4 +/- 1.0 ! Include at least V and B-V Comments: Fixed_Targets ! Section 5.1 Target_Number: 4 Target_Name: QSO1308+326 Alternate_Names: Description: GALAXY,BL Lac Position: RA=13H 10M 28.7S +/- 0.5S, DEC=+32D 20' 43.8" +/- 0.5" ! Most common specification format is ! RA=0H 0M 0.00S +/- 0S, ! DEC=0D 0' 0.0" +/- 0", ! PLATE-ID=0000 Equinox: J2000 RV_or_Z: Z = 0.997 RA_PM: ! Units are seconds of time per year Dec_PM: ! Units are seconds of arc per year Epoch: Annual_Parallax: Flux: V=19.0 +/- 4.0 ! Include at least V and B-V 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 ! 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