! Proposal 5896, submission 4 ! PI: Daniel Welty ! Received Fri Nov 17 15:21:21 EST 1995 ! From: welty@celeborn.uchicago.edu ! Hubble Space Telescope Cycle 5 (1995) Phase II Proposal Template ! $Id: 5896,v 7.1 1995/11/28 18:30:41 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: Alice Berman ! Phone: 410 338-4462 , E-mail: aberman@stsci.edu ! ! This partially completed template was generated from a Phase I proposal. ! Proposal_Information ! Section 4 Title: Detailed Studies of High-Velocity Ionized Gas in the Galactic Disk Proposal_Category: GO Scientific_Category: Interstellar Medium Cycle: 5 Investigators PI_name: Daniel Welty PI_Institution: University of Chicago CoI_Name: Lewis Hobbs CoI_Institution: University of Chicago Contact: ! Y or N (designate at most one contact) CoI_Name: Donald Morton CoI_Institution: Herzberg Institute of Astrophysics Contact: ! Y or N (designate at most one contact) CoI_Name: Lyman Spitzer CoI_Institution: Princeton University Contact: ! Y or N (designate at most one contact) CoI_Name: Donald York CoI_Institution: University of Chicago Contact: ! Y or N (designate at most one contact) Abstract: ! Free format text (please update) The study of high-velocity gas can provide significant information on such topics as the structure and evolution of interstellar shocks, the transfer of energy from stars to the ISM, and the processing of interstellar dust grains. We propose to obtain sensitive new GHRS echelle spectra toward three stars known to exhibit absorption due to high-velocity ionized gas. The goals of the proposed work are to determine the detailed properties of the individual subcomponents in the high-velocity gas and to identify characteristics of this gas useful for distinguishing it from ionized gas arising in other physical environments (e.g., photoionized H II regions, circumstellar shells). Accurate individual component column densities, line widths, and velocities for C II, C II*, C IV, Mg II, Al II, Al III, Si II, Si III, Si IV, S II, S III, and Fe II (essentially all the potentially detectable species) will yield estimates of the temperatures, densities, sizes, ionization characteristics, and depletions for the individual clouds. An understanding of both the prevalence and the detailed physical properties of high- velocity gas in our own Galaxy will aid in understanding the abundances and physical processes characterizing the absorption-line systems seen at various redshifts in the spectra of background QSOs, and thus in understanding crucial aspects of the evolution of galaxies. Questions ! Free format text (please update) Observing_Description: We will need sufficient resolution (to get N, b, v for individual components) and sensitivity (to get weak lines due to S II, S III, Fe II, Al III, C II*) for as many of the accessible, potentially significant ionization states as possible (Table 1) - in order to obtain adequate diagnostics for evaluating shock models and to obtain accurate total abundances for as many elements as possible. Thus we will use ECH-A and ECH-B, and aim for S/N ~ 100 (where practical), which will yield 2-sigma equivalent width limits of 0.7-1.6 mAngstrom\ over the range of wavelengths to be observed. We will use 23 Ori as an example for calculation of exposure times and orbits (see Table 1, where exposure time calculation includes a factor 2 for proper diode sampling and a factor 0.54 for background time and use of SSA). Some settings will be omitted for stars where the lines are expected to be too weak; some strong lines will be observed at slightly reduced S/N. Table 1 Wave Primary Flux inst. blaze count t_exp (min) Species sens. rate S/N=100 1190 SiII,SIII 1.2e-09 0.46e11 0.93 28 12 1206 SiIII 1.2e-09 0.46e11 0.82 24 14 1259 SII,SiII 1.2e-09 0.92e11 0.89 60 6 1335 CII,CII* 1.0e-09 1.34e11 0.98 71 5 1400 SiIV 7.8e-10 1.47e11 0.96 59 6 1550 CIV 6.0e-10 0.64e11 0.86 18 19 1670 AlII 6.8e-10 0.44e11 0.86 12 27 1858 AlIII 4.8e-10 1.62e11 0.78 33 10 2600 FeII 2.2e-10 13.0e11 0.48 74 5 2800 MgII 1.6e-10 12.8e11 0.96 106 3 2852 MgI 1.4e-10 12.8e11 0.60 58 6 For 23 Ori, we have 52 min visibility per orbit; acquisition can be with mirror N1. For orbit 1, we have 12 min guide star + 19 min SSA acq + 3 min spybal + 18 min for two ECH-A spectra (10 min exposure, two 4 min overhead). For orbit 2, we have 6 min guide star + 46 min for 3 ECH-A spectra (34 min exp + three 4 min OH). We switch to ECH-B during occultation. For orbit 3, we have 6 min guide star + 3 min spybal + 42 min for 3 ECH-B spectra (30 min exp + three 4 min OH). The line of sight to Zeta Ori will be particularly useful, as shorter wavelength data for C III, N II, N III, and H I are available from Copernicus; Fe III may be available for Zeta Ori from recent IMAPS observations. Real_Time_Justification: Calibration_Justification: ! Move appropriate text from Real_Time_Justification Additional_Comments: Fixed_Targets ! Section 5.1 Target_Number: 1 Target_Name: HD35149 Alternate_Names: 23-ORI, GSC105-2800 Description: STAR, B0-B2 V-IV Position: RA = 05H 22M 49.87S +/- 0.01S, DEC = +03D 32' 39.8" +/- 0.1" Equinox: J2000 RV_or_Z: V = +18 RA_PM: +0.0000 ! Units are seconds of time per year Dec_PM: +0.0000 ! Units are seconds of arc per year Epoch: 2000 Annual_Parallax: 0.002 Flux: V=5.00 +/- 0.02, B-V=-0.15 +/- 0.02, TYPE=B1V, E(B-V)=0.11, F(1400) = 7.8 +/- 0.2 E-10, F(2800) = 1.6 +/- 0.2 E-10 Comments: Coordinates from Hipparcos INCA Target_Number: 2 Target_Name: HD37742 Alternate_Names: ZETA-ORI, GSC4771-1188 Description: STAR, SUPERGIANT O Position: RA = 05H 40M 45.52S +/- 0.01S, DEC = -01D 56' 33.5" +/- 0.1" Equinox: J2000 RV_or_Z: V = +18 RA_PM: +0.0000 ! Units are seconds of time per year Dec_PM: +0.0000 ! Units are seconds of arc per year Epoch: 2000 Annual_Parallax: 0.002 Flux: V=2.05 +/- 0.02, B-V=-0.21 +/- 0.02, TYPE=O9Ibe, E(B-V)=0.07, F(1400) = 2.0 +/- 0.2 E-08, F(2800) = 4.2 +/- 0.2 E-09 Comments: Coordinates from Hipparcos INCA Target_Number: 3 Target_Name: HD57061 Alternate_Names: TAU-CMA, GSC6541-4204 Description: STAR, SUPERGIANT O Position: RA = 07H 18M 42.50S +/- 0.01S, DEC = -24D 57' 16.0" +/- 0.1" Equinox: J2000 RV_or_Z: V = +40 RA_PM: +0.0000 ! Units are seconds of time per year Dec_PM: +0.0000 ! Units are seconds of arc per year Epoch: 2000 Annual_Parallax: 0.001 Flux: V=4.40 +/- 0.02, B-V=-0.15 +/- 0.02, TYPE=O9Ib, E(B-V)=0.13, F(1400) = 1.0 +/- 0.2 E-09, F(2800) = 3.5 +/- 0.2 E-10 Comments: Coordinates from Hipparcos INCA Visits ! Section 6 ! 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