! Proposal 6164, submission 2 ! PI: Lyman Spitzer, Jr. ! Received Tue Aug 1 16:41:56 EDT 1995 ! From: fitz@astro.Princeton.EDU ! Hubble Space Telescope Cycle 5 (1995) Phase II Proposal ! Lyman Spitzer, P.I. ! Director's Discretionary Time Continuation ! Proposal_Information Title: Composition of Gas in Individual Interstellar Clouds: Cycle 5 DDT Observations Proposal_Category: GO/DD Scientific_Category: Interstellar Medium Cycle: 5 Investigators PI_name: Lyman Spitzer PI_Institution: Princeton University Observatory CoI_name: Edward L. Fitzpatrick CoI_Institution: Princeton University Observatory Contact: Y Abstract: In this Cycle 5 DDT program, spectroscopic observations of interstellar absorption lines will be made towards 2 stars in the Galactic disk using the Goddard High Resolution Spectrograph in its highest resolution modes. The star HD160578 will be observed with both the Ech-A and Ech-B modes. The star HD202904 will be observed only with the Ech-A; these data will be combined with Ech-B observations to be obtained for this star with a Cycle 5 GTO program. All these data will be analyzed to determine column densities in individual interstellar clouds for approximately 19 species from 11 different elements. These measurements will determine how the composition of the gas in such clouds and the various physical processes occurring vary with cloud parameters such as H column density, velocity, ionization level, and distance z from the galactic plane. This information should help to clarify the many physical processes occurring in interstellar gas. Questions Observing_Description: Much pioneering work on the study of individual interstellar clouds has been done from the ground. However, to obtain data on many elements, including the highly-ionized species, requires observations from above the atmosphere. The Copernicus satellite made important contributions to this topic, but its resolving power of 20,000 was insufficient to resolve clearly many of the individual components in most lines of sight; although in favorable cases properties of individual clouds were successfully deduced. The IUE satellite has been enormously useful for broad surveys of interstellar absorption, especially for the fainter stars which could not be observed with Copernicus, but its resolving power of 10,000 is inadequate for resolving most components. The HST, with its resolving power of 85,000 for lines observed with Echelle A and Echelle B, can answer detailed questions on the physical properties of individual clouds towards many stars. Two stars in the Galactic disk, HD160578 and HD202904, will be observed under this Cycle 5 DDT program. The observations will follow the pattern set in previous cycles. In general, we require for each star observations of a series of interstellar lines -- using the Echelle A for lines shortward of 1800 A and the Echelle B for lines longward of 1800 A. The use of the echelles and the Small Science Aperture (SSA) will yield the highest resolution available with the GHRS (resolving power R about 85,000). For photometric accuracy, the FP-SPLIT mode is used to give four adjacent exposures of each line. Lines from 19 different species, corresponding to 11 different elements, are included in the observations, namely, C I, C II, C IV, N V, O I, Mg I, Mg II, S I, S II, S III, Si II, Si III, Si IV, P II, P III, Mn II, Cr II, Fe II, and Zn II. Since Echelle B observations for HD202904 will be acquired in a separate Cycle 5 GTO program, for this star we will obtain only Echelle A data under this DDT program. The scientific goal of the program is to determine column densities in individual interstellar clouds for each of the many species included in the observations. These measurements will determine how the composition of the gas in such clouds and the various physical processes occurring vary with cloud parameters such as H column density, velocity, ionization level, and distance z from the galactic plane. This information should help to clarify the many physical processes occurring in interstellar gas. The program should also increase our understanding of the balance between formation and destruction of interstellar dust grains. Real_Time_Justification: There are no special requirements. Calibration_Justification: There are no coordinated and/or supporting observations. Additional_Comments: There are no additional comments. ! ! ***** TARGET LIST FOLLOWS ****** ! Fixed_Targets ! Target data updated 8/2/95 - AFB Target_Number: 25 Target_Name: HD160578 Alternate_Names: KAPPA-SCO, GSC7885-02065 Description: STAR, B0-B2 III-I Position: RA = 17H 42M 29.28S +/- 0.01S, DEC = -39D 01' 48.1" +/- 0.1" Equinox: J2000 Epoch: 2000.000 Flux: F-CONT(1300) = 1.7 +/- 0.2 E-8, V = 2.41 +/- 0.05, B-V = -0.22, TYPE = B1.5 III Comments: Coordinates are from Hipparcos INCA Target_Number: 27 Target_Name: HD202904 Alternate_Names: UPSILON-CYGNI, GSC2710-02647 Description: STAR, BE Position: RA = 21H 17M 55.06S +/- 0.01S, DEC = 34D 53' 48.5" +/- 0.1" Equinox: J2000 Epoch: 2000.000 Flux: F-CONT(1300) = 5.0 +/- 0.2 E-10, V = 4.43 +/- 0.05, B-V = -0.11, TYPE = B2 Ve Comments: Coordinates are from Hipparcos INCA ! ! ***** VISIT/EXPOSURE LOGSHEET FOLLOWS ***** ! Visits Visit_Number: 1 Exposure_Number: 1 Target_Name: HD160578 Config: HRS Opmode: ACQ Aperture: 2.0 Sp_Element: MIRROR-A1 Time_Per_Exposure: 1.8S Special_Requirements: ONBOARD ACQ FOR 2 Comments: STEP-TIME = 0.2 SEC Exposure_Number: 2 Target_Name: HD160578 Config: HRS Opmode: ACQ/PEAKUP Aperture: 0.25 Sp_Element: MIRROR-A1 Time_Per_Exposure: 5.0S Special_Requirements: ONBOARD ACQ FOR 3 Comments: STEP-TIME = 0.2 SEC Exposure_Number: 3 Target_Name: HD160578 Config: HRS Opmode: ACQ/PEAKUP Aperture: 0.25 Sp_Element: MIRROR-A1 Time_Per_Exposure: 5.0S Special_Requirements: ONBOARD ACQ FOR 4-12 Comments: STEP-TIME = 0.2 SEC Exposure_Number: 4 Target_Name: HD160578 Config: HRS Opmode: ACCUM Aperture: 0.25 Sp_Element: ECH-A Wavelength: 1192.53 Optional_Parameters: FP-SPLIT=DSFOUR, STEP-PATT=DEF, COMB=TWO Number_of_Iterations: 1 Time_Per_Exposure: 326.40S Exposure_Number: 5 Target_Name: HD160578 Config: HRS Opmode: ACCUM Aperture: 0.25 Sp_Element: ECH-A Wavelength: 1241.00 Optional_Parameters: FP-SPLIT=DSFOUR, STEP-PATT=DEF, COMB=TWO Number_of_Iterations: 1 Time_Per_Exposure: 217.60S Exposure_Number: 6 Target_Name: HD160578 Config: HRS Opmode: ACCUM Aperture: 0.25 Sp_Element: ECH-A Wavelength: 1252.89 Optional_Parameters: FP-SPLIT=DSFOUR, STEP-PATT=DEF, COMB=TWO Number_of_Iterations: 1 Time_Per_Exposure: 163.20S Exposure_Number: 7 Target_Name: HD160578 Config: HRS Opmode: ACCUM Aperture: 0.25 Sp_Element: ECH-A Wavelength: 1262.22 Optional_Parameters: FP-SPLIT=DSFOUR, STEP-PATT=DEF, COMB=TWO Number_of_Iterations: 1 Time_Per_Exposure: 217.60S Exposure_Number: 8 Target_Name: HD160578 Config: HRS Opmode: ACCUM Aperture: 0.25 Sp_Element: ECH-A Wavelength: 1303.47 Optional_Parameters: FP-SPLIT=DSFOUR, STEP-PATT=DEF, COMB=TWO Number_of_Iterations: 1 Time_Per_Exposure: 108.80S Exposure_Number: 9 Target_Name: HD160578 Config: HRS Opmode: ACCUM Aperture: 0.25 Sp_Element: ECH-A Wavelength: 1335.32 Optional_Parameters: FP-SPLIT=DSFOUR, STEP-PATT=DEF, COMB=TWO Number_of_Iterations: 1 Time_Per_Exposure: 108.80S Exposure_Number: 10 Target_Name: HD160578 Config: HRS Opmode: ACCUM Aperture: 0.25 Sp_Element: ECH-A Wavelength: 1393.97 Optional_Parameters: FP-SPLIT=DSFOUR, STEP-PATT=DEF, COMB=TWO Number_of_Iterations: 1 Time_Per_Exposure: 163.20S Exposure_Number: 11 Target_Name: HD160578 Config: HRS Opmode: ACCUM Aperture: 0.25 Sp_Element: ECH-A Wavelength: 1549.71 Optional_Parameters: FP-SPLIT=DSFOUR, STEP-PATT=DEF, COMB=TWO Number_of_Iterations: 1 Time_Per_Exposure: 326.40S Exposure_Number: 12 Target_Name: HD160578 Config: HRS Opmode: ACCUM Aperture: 0.25 Sp_Element: ECH-A Wavelength: 1561.10 Optional_Parameters: FP-SPLIT=DSFOUR, STEP-PATT=DEF, COMB=TWO Number_of_Iterations: 1 Time_Per_Exposure: 326.40S Visit_Number: 2 Exposure_Number: 1 Target_Name: HD160578 Config: HRS Opmode: ACQ Aperture: 2.0 Sp_Element: MIRROR-A1 Time_Per_Exposure: 1.8S Special_Requirements: ONBOARD ACQ FOR 2 Comments: STEP-TIME = 0.2 SEC Exposure_Number: 2 Target_Name: HD160578 Config: HRS Opmode: ACQ/PEAKUP Aperture: 0.25 Sp_Element: MIRROR-A1 Time_Per_Exposure: 5.0S Special_Requirements: ONBOARD ACQ FOR 3 Comments: STEP-TIME = 0.2 SEC Exposure_Number: 3 Target_Name: HD160578 Config: HRS Opmode: ACQ/PEAKUP Aperture: 0.25 Sp_Element: MIRROR-A1 Time_Per_Exposure: 5.0S Special_Requirements: ONBOARD ACQ FOR 4-12 Comments: STEP-TIME = 0.2 SEC Exposure_Number: 4 Target_Name: HD160578 Config: HRS Opmode: ACCUM Aperture: 0.25 Sp_Element: ECH-A Wavelength: 1355.80 Optional_Parameters: FP-SPLIT=DSFOUR, STEP-PATT=DEF, COMB=TWO Number_of_Iterations: 1 Time_Per_Exposure: 326.40S Exposure_Number: 5 Target_Name: HD160578 Config: HRS Opmode: ACCUM Aperture: 0.25 Sp_Element: ECH-B Wavelength: 1807.93 Optional_Parameters: FP-SPLIT=DSFOUR, STEP-PATT=DEF, COMB=TWO Number_of_Iterations: 1 Time_Per_Exposure: 380.80S Exposure_Number: 6 Target_Name: HD160578 Config: HRS Opmode: ACCUM Aperture: 0.25 Sp_Element: ECH-B Wavelength: 2027.00 Optional_Parameters: FP-SPLIT=DSFOUR, STEP-PATT=DEF, COMB=TWO Number_of_Iterations: 1 Time_Per_Exposure: 217.60S Exposure_Number: 7 Target_Name: HD160578 Config: HRS Opmode: ACCUM Aperture: 0.25 Sp_Element: ECH-B Wavelength: 2059.77 Optional_Parameters: FP-SPLIT=DSFOUR, STEP-PATT=DEF, COMB=TWO Number_of_Iterations: 1 Time_Per_Exposure: 217.60S Exposure_Number: 8 Target_Name: HD160578 Config: HRS Opmode: ACCUM Aperture: 0.25 Sp_Element: ECH-B Wavelength: 2261.12 Optional_Parameters: FP-SPLIT=DSFOUR, STEP-PATT=DEF, COMB=TWO Number_of_Iterations: 1 Time_Per_Exposure: 108.80S Exposure_Number: 9 Target_Name: HD160578 Config: HRS Opmode: ACCUM Aperture: 0.25 Sp_Element: ECH-B Wavelength: 2371.36 Optional_Parameters: FP-SPLIT=DSFOUR, STEP-PATT=DEF, COMB=TWO Number_of_Iterations: 1 Time_Per_Exposure: 108.80S Exposure_Number: 10 Target_Name: HD160578 Config: HRS Opmode: ACCUM Aperture: 0.25 Sp_Element: ECH-B Wavelength: 2603.71 Optional_Parameters: FP-SPLIT=DSFOUR, STEP-PATT=DEF, COMB=TWO Number_of_Iterations: 1 Time_Per_Exposure: 108.80S Exposure_Number: 11 Target_Name: HD160578 Config: HRS Opmode: ACCUM Aperture: 0.25 Sp_Element: ECH-B Wavelength: 2800.36 Optional_Parameters: FP-SPLIT=DSFOUR, STEP-PATT=DEF, COMB=TWO Number_of_Iterations: 1 Time_Per_Exposure: 108.80S Exposure_Number: 12 Target_Name: HD160578 Config: HRS Opmode: ACCUM Aperture: 0.25 Sp_Element: ECH-B Wavelength: 2853.39 Optional_Parameters: FP-SPLIT=DSFOUR, STEP-PATT=DEF, COMB=TWO Number_of_Iterations: 1 Time_Per_Exposure: 108.80S Visit_Number: 3 Exposure_Number: 1 Target_Name: HD202904 Config: HRS Opmode: ACQ Aperture: 2.0 Sp_Element: MIRROR-N1 Time_Per_Exposure: 1.8S Special_Requirements: ONBOARD ACQ FOR 2 Comments: STEP-TIME = 0.2 SEC Exposure_Number: 2 Target_Name: HD202904 Config: HRS Opmode: ACQ/PEAKUP Aperture: 0.25 Sp_Element: MIRROR-N1 Time_Per_Exposure: 5.0S Special_Requirements: ONBOARD ACQ FOR 3-11 Comments: STEP-TIME = 0.2 SEC Exposure_Number: 3 Target_Name: HD202904 Config: HRS Opmode: ACCUM Aperture: 0.25 Sp_Element: ECH-A Wavelength: 1192.53 Optional_Parameters: FP-SPLIT=DSFOUR, STEP-PATT=DEF Number_of_Iterations: 1 Time_Per_Exposure: 1523.20S Exposure_Number: 4 Target_Name: HD202904 Config: HRS Opmode: ACCUM Aperture: 0.25 Sp_Element: ECH-A Wavelength: 1241.00 Optional_Parameters: FP-SPLIT=DSFOUR, STEP-PATT=DEF Number_of_Iterations: 1 Time_Per_Exposure: 870.40S Exposure_Number: 5 Target_Name: HD202904 Config: HRS Opmode: ACCUM Aperture: 0.25 Sp_Element: ECH-A Wavelength: 1252.89 Optional_Parameters: FP-SPLIT=DSFOUR, STEP-PATT=DEF Number_of_Iterations: 1 Time_Per_Exposure: 652.80S Exposure_Number: 6 Target_Name: HD202904 Config: HRS Opmode: ACCUM Aperture: 0.25 Sp_Element: ECH-A Wavelength: 1262.22 Optional_Parameters: FP-SPLIT=DSFOUR, STEP-PATT=DEF Number_of_Iterations: 1 Time_Per_Exposure: 870.40S Exposure_Number: 7 Target_Name: HD202904 Config: HRS Opmode: ACCUM Aperture: 0.25 Sp_Element: ECH-A Wavelength: 1303.47 Optional_Parameters: FP-SPLIT=DSFOUR, STEP-PATT=DEF Number_of_Iterations: 1 Time_Per_Exposure: 544.00S Exposure_Number: 8 Target_Name: HD202904 Config: HRS Opmode: ACCUM Aperture: 0.25 Sp_Element: ECH-A Wavelength: 1335.32 Optional_Parameters: FP-SPLIT=DSFOUR, STEP-PATT=DEF Number_of_Iterations: 1 Time_Per_Exposure: 544.00S Exposure_Number: 9 Target_Name: HD202904 Config: HRS Opmode: ACCUM Aperture: 0.25 Sp_Element: ECH-A Wavelength: 1393.97 Optional_Parameters: FP-SPLIT=DSFOUR, STEP-PATT=DEF Number_of_Iterations: 1 Time_Per_Exposure: 544.00S Exposure_Number: 10 Target_Name: HD202904 Config: HRS Opmode: ACCUM Aperture: 0.25 Sp_Element: ECH-A Wavelength: 1549.71 Optional_Parameters: FP-SPLIT=DSFOUR, STEP-PATT=DEF Number_of_Iterations: 1 Time_Per_Exposure: 979.20S Exposure_Number: 11 Target_Name: HD202904 Config: HRS Opmode: ACCUM Aperture: 0.25 Sp_Element: ECH-A Wavelength: 1561.10 Optional_Parameters: FP-SPLIT=DSFOUR, STEP-PATT=DEF Number_of_Iterations: 1 Time_Per_Exposure: 870.40S ! ! ***** DATA DISTRIBUTION FOLLOWS ***** ! Data_Distribution ! Defaults indicated; change if desired Medium: 8MM ! 8MM or 6250BPI or 1600BPI Blocking_Factor: 10 ! 10 or 1 ! Only astronomers with very old 9- ! track tape drives should consider ! a blocking factor of 1 Ship_To: PI_address ! Ship_Via: UPS ! UPS (2-day) or OVERNIGHT ! Overnight shipping done at PI expense Recipient_Email: !fitz@astro.princeton.edu