! $Id: 5739,v 6.1 1994/07/27 20:46:35 pepsa Exp $ coverpage: title_1: ULTRAVIOLET SPECTROSCOPY OF A HIGH-LATITUDE MOLECULAR CLOUD: title_2: CARRYOVER sci_cat: INTERSTELLAR MEDIUM sci_subcat: ABSORPTION LINES proposal_for: GO/CAR cont_id: 4458 pi_fname: EWINE pi_mi: F. pi_lname: VAN DISHOECK pi_inst: LEIDEN OBSERVATORY pi_country: THE NETHERLANDS hours_pri: 9.55 num_pri: 1 hrs: Y funds_length: 12 off_fname: HARM off_mi: J. off_lname: HABING off_title: DIRECTOR off_inst: LEIDEN OBSERVATORY off_addr_1: P.O. BOX 9513 off_city: 2300 RA LEIDEN off_country: THE NETHERLANDS off_phone: 31-71-275859 ! end of coverpage abstract: line_1: We propose to investigate the composition of and physical conditions line_2: in an isolated, well-characterized high-latitude molecular cloud line_3: through high-resolution UV absorption spectroscopy. Observations line_4: at 6 carefully chosen grating settings will determine the abundances line_5: and excitation of at least 9 different atomic species and 5 different line_6: molecules. The measurements will provide diagnostic probes of density, line_7: temperature, and electron fraction that should be more stringent line_8: than those available through ground-based measurements. Accurate line_9: determinations of the abundances of the principal forms of interstellar line_10: carbon (C+, C, 12CO and 13CO), combined with existing CO millimeter line_11: data, will afford rigorous, unique tests of theories of the line_12: small-scale structure and chemistry of interstellar clouds. Such line_13: tests are crucial because this high-latitude cloud evidently line_14: occupies the regime of parameter space in which molecular line_15: species are just beginning to dominate all gas-phase abundances. ! ! end of abstract general_form_proposers: lname: VAN DISHOECK fname: EWINE title: PI mi: F. inst: 6870 country: THE NETHERLANDS esa: Y ! lname: SPAANS fname: MARCO mi: C. inst: 6870 country: THE NETHERLANDS esa: Y ! lname: BLACK fname: JOHN mi: H. inst: 1212 country: U.S.A. ! ! end of general_form_proposers block general_form_text: question: 3 section: 1 line_1: 3. Short description of proposed observations line_2: We will exploit the unique advantages of UV absorption spectroscopy line_3: in the investigation of a single high-latitude cloud. Interstellar line_4: absorption lines of various atoms and molecules will be measured with line_5: the GHRS. Of prime importance are the observations of the principal line_6: carbon-bearing species C+,C, 12CO and 13CO at 2325, 1613, 1477 line_7: and 1421 A. The long exposure time at 2325 A is chosen such that line_8: a limiting equivalent width of <1 mA (S/N=90 per diode) line_9: is reached. At wavelengths longer than 2000 A, the ECH-B line_10: will be used, whereas at shorter wavelengths, ECH-A is chosen. line_11: The LSA is used to obtain maximum S/N. line_12: Since the UV flux decreases rapidly at shorter wavelengths, line_13: the S/N will be less for the ECH-A settings. Our observing plan line_14: also covers other important molecules, such as CS, SO and OH at line_15: 2582 and 3078 A. Substepping routines and comb addition will line_16: be used aimed at optimizing the S/N. ! question: 3 section: 2 line_1: Table with Grating settings line_2: ================================================================== line_3: Wavelength Grating Priority Species line_4: ------------------------------------------------------------------ line_5: 1421.8 ECH-A 1 CO, 13CO, S I line_6: 1478.2 ECH-A 1 CO, 13CO, S I line_7: 1613.1 ECH-A 1 C I], Fe II, Si I line_8: 2325.0 ECH-B 1 C II], Ni I line_9: 2581.5 ECH-B 1 CS, SO, Fe II, Mn II line_10: 3078.0 ECH-B 1 OH, Al I, Ti II line_11: ------------------------------------------------------------------- line_12: All observations will be made in the LSA. Substepping will be used, line_13: along with the FP-SPLIT feature, to minimize fixed-pattern noise due line_14: to diode-to-diode sensitivity variations. The long exposure at 2325 A line_15: will be divided into two different grating settings to minimize line_16: systematic noise. ! question: 4 section: 1 line_1: 4. Justify need for HST line_2: The GHRS on HST is the only instrument capable of performing line_3: medium to high-resolution observations of interstellar absorption line_4: lines in the ultraviolet. The sensitivity of IUE is inadequate, and line_5: the high-latitude stars were not covered with Copernicus. Resonance lines line_6: of most atomic species are accessible only in the ultraviolet: this applies line_7: to all of the chemically most important species. The absorption line technique line_8: itself insures that all measurements refer to the same absorbing column. line_9: Column densities can be determined from such measurements with greater line_10: accuracy than with ground-based millimeter wave techniques. We have already line_11: obtained extensive ground-based data on optical absorption lines and mm/submm line_12: emission lines in the cloud we propose to observe here. ! question: 4 section: 2 line_1: Justify amount of exposure time line_2: The scientific goals require minimum detectable equivalent widths in line_3: the range 1-5 mA at wavelengths above 2000 A, corresponding to S/N ratios line_4: of 50 or more per resolution element. At shorter wavelengths, S/N ratios line_5: of 20 are sufficient, based on our expected line strengths. line_6: The required exposure times have been estimated through the use of line_7: the tabulated sensitivities (May 1994, HST GHRS handbook 5.0), as well line_8: as through our Cycle 1 observations of the translucent cloud toward line_9: HD 154368. The continuum fluxes of the star are taken line_10: from IUE observations of Welty and Fowler (1991, ApJ 393,193). ! question: 5 section: 1 line_1: No special scheduling requests. ! question: 6 section: 1 line_1: Pt-lamb calibration exposures are requested for all line_2: wavelength settings in order to provide more accurate velocities line_3: for comparison with ground-based optical and millimeter data, and line_4: to aid in the analysis of the band structure. ! ! question: 9 section: 1 line_1: The applicants are coinvestigators on GO program 2415 "Physical and line_2: Chemical Processes in Dense Interstellar Clouds" (PI=T.P. Snow), which line_3: has been awarded time in Cycle 1, for which a first paper is line_4: about to be submitted. The current proposal has no direct overlap with line_5: that program, but does represent a natural extension of it to a distinct line_6: class of interstellar clouds. Several of the wavelength settings are the line_7: same as in that proposal. ! question: 9 section: 2 line_1: See proposal of Snow et al. for summary main results. ! question: 10 section: 1 line_1: The home institutions provide basic salary support and facilities for the line_2: investigators, plus support and facilities for their research students. line_3: In particular, computing facilities in the form of SUN workstations and line_4: network access are provided. The PI has a special PIONIER grant from the line_5: Netherlands Organization for the Advancement of Pure Research, which is line_6: used to provide support for graduate student Marco Spaans in Leiden, who line_7: will be responsible for most of the model calculations. ! !end of general form text general_form_address: lname: VAN DISHOECK fname: EWINE mi: F. category: PI inst: LEIDEN OBSERVATORY addr_1: P.O. BOX 9513 city: 2300 RA LEIDEN country: THE NETHERLANDS phone: 31-71-275874 telex: 39058 ASTRO ! ! end of general_form_address records fixed_targets: targnum: 1 name_1: HD210121 name_2: GSC5227352 descr_1: A,111,G,511,513 pos_1: RA=22H 08M 11.884S +/- 0.5", pos_2: DEC=-03D 31' 53.12" +/- 0.3", pos_3: PLATE-ID = 00GX equinox: J2000 pos_epoch_bj: J pos_epoch_yr: 2000.00 rv_or_z: V=-14 comment_1: PLATE-ID=00GX. comment_2: POS. MEAS. BY ANNE GONNELLA STSCI comment_3: POS. WITHIN 0.4" OF INCA POSITION fluxnum_1: 1 fluxval_1: V=7.67, TYPE=B3V fluxnum_2: 1 fluxval_2: B-V=+0.20 fluxnum_3: 2 fluxval_3: E(B-V)=0.3 fluxnum_4: 4 fluxval_4: F(3078)=3.7 E-12 fluxnum_5: 5 fluxval_5: F(2582)=2.9 E-12 fluxnum_6: 6 fluxval_6: F(2325)=2.4 E-12 fluxnum_7: 7 fluxval_7: F(1613)=2.4 E-12 fluxnum_8: 8 fluxval_8: F(1477)=2.0 E-12 fluxnum_9: 9 fluxval_9: F(1422)=1.5 E-12 ! ! end of fixed targets ! No solar system records found ! No generic target records found exposure_logsheet: linenum: 1.000 targname: HD210121 config: HRS opmode: ACQ aperture: 2.0 sp_element: MIRROR-N2 num_exp: 1 time_per_exp: 1.8S s_to_n: 100 fluxnum_1: 1 priority: 1 param_1: LOCATE=YES,BRIGHT=RETURN param_2: SEARCH-SIZE=3 req_1: CYCLE 4; req_2: ONBOARD ACQ FOR 2-16 comment_1: STEP-TIME=0.2S comment_2: EXPECT 60000 COUNTS IN STEP-TIME ! linenum: 2.000 targname: HD210121 config: HRS opmode: ACQ/PEAKUP aperture: 2.0 sp_element: MIRROR-N2 num_exp: 1 time_per_exp: 20.4S s_to_n: 100 fluxnum_1: 1 priority: 1 req_1: CYCLE 4; req_2: ONBOARD ACQ FOR 3-16 comment_1: STEP-TIME=0.2S comment_2: EXPECT 60000 COUNTS IN STEP-TIME ! linenum: 3.000 targname: WAVE config: HRS opmode: ACCUM aperture: SC2 sp_element: ECH-B wavelength: 2325.0 num_exp: 1 time_per_exp: 40S priority: 1 req_1: CYCLE 4; req_2: CALIB FOR 4.0 NO SLEW; req_3: SEQ 3-4 NO GAP ! linenum: 4.000 targname: HD210121 config: HRS opmode: ACCUM aperture: 2.0 sp_element: ECH-B wavelength: 2325.0 num_exp: 3 time_per_exp: 970S fluxnum_1: 6 priority: 1 param_1: FP-SPLIT=STD, param_2: STEP-PATT=7, req_1: CYCLE 4; comment_1: S_TO_N ESTIMATE 92 comment_2: FIRST PART OF 2325 SETTING ! linenum: 5.000 targname: WAVE config: HRS opmode: ACCUM aperture: SC2 sp_element: ECH-B wavelength: 2325.8 num_exp: 1 time_per_exp: 40S priority: 1 req_1: CYCLE 4; req_2: CALIB FOR 6.0 NO SLEW; req_3: SEQ 5-6 NO GAP ! linenum: 6.000 targname: HD210121 config: HRS opmode: ACCUM aperture: 2.0 sp_element: ECH-B wavelength: 2325.8 num_exp: 3 time_per_exp: 970S fluxnum_1: 6 priority: 1 param_1: FP-SPLIT=STD, param_2: STEP-PATT=7, req_1: CYCLE 4; comment_1: S_TO_N ESTIMATE 92 comment_2: SECOND PART OF 2325 SETTING ! linenum: 7.000 targname: WAVE config: HRS opmode: ACCUM aperture: SC2 sp_element: ECH-B wavelength: 2581.5 num_exp: 1 time_per_exp: 40S priority: 1 req_1: CYCLE 4; req_2: CALIB FOR 8.0 NO SLEW; req_3: SEQ 7-8 NO GAP ! linenum: 8.000 targname: HD210121 config: HRS opmode: ACCUM aperture: 2.0 sp_element: ECH-B wavelength: 2581.5 num_exp: 3 time_per_exp: 1000S fluxnum_1: 5 priority: 1 param_1: FP-SPLIT=STD, param_2: STEP-PATT=7, req_1: CYCLE 4; comment_1: S_TO_N ESTIMATE 79 ! linenum: 9.000 targname: WAVE config: HRS opmode: ACCUM aperture: SC2 sp_element: ECH-B wavelength: 3078.0 num_exp: 1 time_per_exp: 40S priority: 1 req_1: CYCLE 4; req_2: CALIB FOR 10.0 NO SLEW; req_3: SEQ 9-10 NO GAP ! linenum: 10.000 targname: HD210121 config: HRS opmode: ACCUM aperture: 2.0 sp_element: ECH-B wavelength: 3078.0 num_exp: 3 time_per_exp: 1000S fluxnum_1: 4 priority: 1 param_1: FP-SPLIT=STD, param_2: STEP-PATT=7, req_1: CYCLE 4; comment_1: S_TO_N ESTIMATE 41 ! linenum: 11.000 targname: WAVE config: HRS opmode: ACCUM aperture: SC2 sp_element: ECH-A wavelength: 1478.2 num_exp: 1 time_per_exp: 40S priority: 1 req_1: CYCLE 4; req_2: CALIB FOR 12.0 NO SLEW; req_3: SEQ 11-12 NO GAP ! linenum: 12.000 targname: HD210121 config: HRS opmode: ACCUM aperture: 2.0 sp_element: ECH-A wavelength: 1478.2 num_exp: 5 time_per_exp: 1000S fluxnum_1: 8 priority: 1 param_1: FP-SPLIT=STD, param_2: STEP-PATT=7, req_1: CYCLE 4; comment_1: S_TO_N ESTIMATE 25 ! linenum: 13.000 targname: WAVE config: HRS opmode: ACCUM aperture: SC2 sp_element: ECH-A wavelength: 1421.8 num_exp: 1 time_per_exp: 40S priority: 1 req_1: CYCLE 4; req_2: CALIB FOR 14.0 NO SLEW; req_3: SEQ 13-14 NO GAP ! linenum: 14.000 targname: HD210121 config: HRS opmode: ACCUM aperture: 2.0 sp_element: ECH-A wavelength: 1421.8 num_exp: 5 time_per_exp: 1000S fluxnum_1: 9 priority: 1 param_1: FP-SPLIT=STD, param_2: STEP-PATT=7, req_1: CYCLE 4; comment_1: S_TO_N ESTIMATE 27 ! linenum: 15.000 targname: WAVE config: HRS opmode: ACCUM aperture: SC2 sp_element: ECH-A wavelength: 1613.1 num_exp: 1 time_per_exp: 40S priority: 1 req_1: CYCLE 4; req_2: CALIB FOR 16.0 NO SLEW; req_3: SEQ 15-16 NO GAP ! linenum: 16.000 targname: HD210121 config: HRS opmode: ACCUM aperture: 2.0 sp_element: ECH-A wavelength: 1613.1 num_exp: 3 time_per_exp: 1200S fluxnum_1: 7 priority: 1 param_1: FP-SPLIT=STD, param_2: STEP-PATT=7, req_1: CYCLE 4; comment_1: S_TO_N ESTIMATE 18 ! ! end of exposure logsheet ! No scan data records found