! $Id: 6314,v 3.1 1995/06/08 11:31:08 pepsa Exp $ Proposal_Information Title: THE LEVEL OF IONIZATION AND CHEMICAL COMPOSITION OF QSO BAL REGION GAS - REPEAT FOR HOPR 230 Proposal_Category: GO Scientific_Category: Quasars Cycle: 4 Investigators PI_Name: DAVID A. TURNSHEK PI_Institution: UNIVERSITY OF PITTSBURGH CoI_Name: BRIAN R. ESPEY CoI_Institution: UNIVERSITY OF PITTSBURGH CoI_Name: RAY J. WEYMANN CoI_Institution: MT WILSON & LAS CAMPANAS OBSERVATORY Abstract: FROM PROGRAM 5455: About 10% of all radio quiet QSOs exhibit broad absorption lines (BALs) in their spectra. The BALs come from a mostly highly ionized region outflowing from the central source at speeds up to many tens of thousands of km/s. Observational constraints on models require that the covering factor of the BAL region be small (e.g., normally < 0.2), therefore many QSOs must have BAL regions which do not lie along our lines-of-sight. For assumptions which should reasonably apply to BAL regions, accurate (algorithm independent) ionic column densities can be derived as a function of outflow velocity for BAL gas. This is unlike the case for broad emission lines in QSOs, which at any observed velocity originates in various components with a range of ionizations. Based on column density analyses, evidence suggests that the chemical composition of the BAL region gas is enhanced by factors of 10 to 100 or more times solar values. Since this conclusion is remarkable, we propose to carefully checked it. One possible problem is that our assumptions about the ability of BAL gas to cover the central source are not universally correct. Another problem with past analyses is that different ionic species of the same element in an object have not been studied. We will remedy these problems by observing the UV spectrum of three specially selected BAL QSOs which currently show the best evidence for enhanced abundances. Constraints on the ionization and chemical composition of the BAL region gas will be derived using Ferland's photoionization code. Questions Observing_Description: FROM PRGRAM 5455: We propose HST observations of 4 QSOs using the FOS G270H mode in order to study the strength and shape of BAL profiles that fall in the spectral region below 3200 Angstroms. The observation of each object can be made during a single visit. The signal-to-noise ratio attained near continuum regions will be approximately 30 per resolution element with resolution R=1300 (4 pixels per resolution element with 1/4 diode substeps). Exposure times range from 34 minutes to 54 minutes. In addition we will observe 6 QSOs using the FOS G160L mode in order to follow the shapes of the continuous energy distributions into the far UV. The signal-to-noise ratio attained near continuum regions at about 1600 Angstroms will be 10 per resolution element with resolution R=200 (4 pixels per resolution element with 1/4 diode substeps), which will be adequate for our purpose. THIS PROGRAM REPEATS 1 FAILED OBSERVATION FROM PROGRAM 5455. Fixed_Targets Target_Number: 4 Target_Name: Q0932+5006 Description: GALAXY, QSO, Radio Quiet Position: RA = 9H 35M 53.01S +/- .1S, DEC = +49D 53' 13.8" +/- .1S, PLATE-ID=00T8 Equinox: 2000 RV_or_Z: Z = 1.92 Flux: V = 17.24 B-V = 0.16 F-CONT(1600) = 8.6 E-16 Comments: PREVIOUSLY OBSERVED WITH HST Visits Visit_Number: 1 Exposure_Number: 7 Target_Name: Q0932+5006 Config: FOS/RD Opmode: ACQ/BINARY Aperture: 4.3 Sp_Element: MIRROR Number_of_Iterations: 1 Time_Per_Exposure: 14.6S Special_Requirements: ONBOARD ACQ FOR 8 Exposure_Number: 8 Target_Name: Q0932+5006 Config: FOS/RD Opmode: ACCUM Aperture: 1.0 Sp_Element: G160L Number_of_Iterations: 1 Time_Per_Exposure: 20M Data_Distribution Medium: 8MM ! 8MM or 6250BPI or 1600BPI Blocking_Factor: 10 ! 10 or 1 Ship_To: PI_Address ! STSCI or PI_Address or Ship_Via: UPS ! UPS (2-day) or OVERNIGHT