! 6830_v3.prop ! Revised by Ray Lucas - 23 July, 1996, based on CS recommendations ! and updated target position measurements, etc. and info from co-I ! Ed Shaya. Target measurements were made by Ray Lucas and Ed Shaya ! using stsdas metric task, etc. ! ! Updated TA Texps to more conservative values as per CS since HOPR ! repeats not as easy these days as we get closer to next Servicing ! Mission. Also corrected values for SCAN-STEP and SEARCH-SIZE as ! per conversation/email with CS. ( They were reversed from what they ! should have been in original CS review. ) - RAL - 23 July, 1996 ! ! Changed Texp for 5th stage of ACQ/PEAK back to 70s since 80s wouldn't ! fit into one orbit and CS said to drop it back to 70s while keeping ! all the first 4 stages at 8s each. - RAL 24 July, 1996 ! ! Changed Texp for 5th stage of ACQ/PEAK from 70s to 24s on CS's advice ! once it became clear that the ACQ/PEAK sequence was still taking one ! orbit too many causing the program to take 7 orbits instead of 6. ! ( NOTE: TAC allocation of 5 orbits was increased to 6 by USCC at ! behest of CS before the latest results were known. ) - RAL - 11/25/96 ! ! Proposal 6830, submission 1 ! PI: Douglas Currie ! Received Sun Feb 11 16:44:10 EST 1996 ! From: shaya@leibnitz.umd.edu ! Hubble Space Telescope Cycle 6 (1996) Phase II Proposal Template ! $Id: 6830,v 8.1 1996/11/25 17:11:07 pepsa Exp $ ! Hubble Space Telescope Cycle 6 (1996) Phase II Proposal Template ! $Id: 6830,v 8.1 1996/11/25 17:11:07 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: Lucas ! Phone: 410-338-4716 , E-mail: lucas@stsci.edu ! ! This partially completed template was generated from a Phase I proposal. ! Name of Phase I Proposal: archive-1158.currie.prop ! Date generated: Fri Dec 22 16:43:14 EST 1995 ! Proposal_Information ! Section 4 Title: FOS Spectroscopy of NGC 1316 (Fornax A) Proposal_Category: GO Scientific_Category: GALAXIES & CLUSTERS Cycle: 6 Investigators PI_name: Douglas Currie PI_Institution: University of Maryland CoI_Name: Edward Shaya CoI_Institution: University of Maryland Contact: ! Y or N (designate at most one contact) Abstract: ! Free format text (please update) The elliptical galaxy NGC 1316, also known as Fornax A, is the third brightest radio source in the sky. It has twin jets on opposite sides of the nucleus, but no opaque radio core. Ground based spectra of the core hint at a rising mass-to- light ratio with increasing resolution and allow the possibility of a 3 * 10^9 M_SUN dark object. Stellar absorption lines are quite strong and easily measured for the purpose of velocity dispersion measurements, but only the HST has the spatial resolution required to focus in on scales where stars would no longer dominate the mass. FOC measurements reveal a central bright bright point source at Lambda1750Angstrom\ which indicates that the center is free of gas and dust. There is also no observable HAlpha observed in the central 1". A spectrum of the inner 0arcs13 (10 pc) in radius, would allow a decisive measurement of the mass of the central engine to be made. The spectra will be analyzed using the Fourier quotient method, a cross-correlation method, and a deconvolution method. Each method will determine a line width and evaluate deviations from a Gaussian line profile. A complete dynamical description of the core of this galaxy will then be possible. Questions ! Free format text (please update) Observing_Description: We propose to use the smallest circular apertures on the FOS (0.26" diameter) to obtain a deep optical spectrum of the central peak of NGC 1316. We are expecting the velocity dispersion to be in excess of Sigma = 190 km s^-1 (no massive dark object) and perhaps as high as 800 km s^-1 (dark object of 3 * 10^9 M_SUN). Experience from similar observations of elliptical galaxies has established that velocity dispersion can be determined to an accuracy of ~ 10\% with signal-to-noise ratio of about 20 per Angstrom (Faber; personal communication). This seems to hold for FOS spectra as well as typical ground based spectra. Each diode covers 4.37 angstroms. So the signal-to-noise ratio per diode should be 87. This signal-to-noise ratio is comparible to the flat field determination errors. The central surface brightness is V=13.6 mag arcsec^-2 which translates into 16.79 mag within the aperture. If a V=15 magnitude G2 star gets 5.1 counts per second per diode at 4600Angstrom (Table 1 -9 of Handbook) and the throughput is 0.86 (Table 1-8), then we expect 5.1*0.86*dex(15-16.8 / 2.5) = 0.85 counts/s. The exposure time is 87^2/0.85 = 8900s = 148 minutes. Although we want high signal-to-noise, positioning is made slightly less critical by the fact that the core of the galaxy fills the selected apertures. I have discussed acquisition of this object in detail with an FOS Instrument Team member. The acquisition will be A+B1+C1+F1+D3. The overhead for this is 7+12+10+10+17 minutes. At the declination of this object, the visibility is typically 54 minutes. Guide star acquisition takes 8 minutes and reacquisition takes 6 minutes. The target acquisition is completed 23 (6+17) minutes into the second orbit. Using the remaining time in the second orbit 31 min plus 3 additional orbits, each with 48 min on target time, totals to 175 minutes on target for a signal-to-noise ratio of 21.6 per angstrom. We will not require the observation of red stars for templates since these have been made by several FOS observations in previous cycles. NOTE: The above Target Acquisition scenario has been modified to that currently in the program as per further work by the Contact Scientist, the PC, and the observers ( co-I Ed Shaya ). The 5th step especially had to be revised further downward in order to keep the program within its newly increased ( from 5 to 6 ) allocation of orbits. Real_Time_Justification: None. Calibration_Justification: ! Move appropriate text from ! Real_Time_Justification None. Additional_Comments: None. Fixed_Targets ! Section 5.1 Target_Number:1 Target_Name: NGC1316-GC Alternate_Names: Description: EXT-CLUSTER,Globular Cluster,CALIBRATION,Aperture Location Position: RA=03H 22M 42.5381S +/- 0.1S, DEC=-37D 12' 41.214" +/- 0.5", PLATE-ID=02IW Equinox: 2000 RV_or_Z: V=+1635 Flux: V=18.5+/-0.2 ! Include at least V and B-V Comments: GC RV is value for galaxy. GC color is V-I=1.7. Assume K2III continuum for GC. GC position is from Westphal's GTO WFPC-I image of NGC 1316. GC is being used as an offset "star" for target acquisition. Guide stars used for Westphal's observations were from GS Plate-ID=02IW. Target_Number:2 Target_Name: NGC1316-NUCLEUS Alternate_Names: FORNAX A Description: GALAXY, RADIO GALAXY, ELLIPTICAL Position: RA=03H 22M 41.7915S +/- 0.1S, DEC=-37D 12' 29.745" +/- 0.5", PLATE-ID=02IW Equinox: 2000 RV_or_Z: V=+1635 Flux: SURF(V)=13.5+/-0.2 ! Include at least V and B-V Comments: Position of nucleus is from Westphal's GTO WFPC-I image of NGC 1316. Guide stars used for Westphal's observations were from GS Plate-ID=02IW. Visits ! Section 6 Visit_Number: 01 Visit_Requirements: ! Section 7.1 ! 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