Page 1 PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID 3759c Report Date: 09-May-96:18:49 Version: ********** Check-in Date: ********** 1.Proposal Title: DUST, MOLECULAR, ATOMIC COMPOSITION AND THE PHYSICAL CONDITIONS IN MOLECULAR CLOUDS ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Proposal Type 5. Continuation ID INTERSTELLAR MEDIUM GO Sub Category DUST ------------------------------------------------------------------------------------ 6. Principal Investigator Institution Country Telephone Francois Boulanger RADIOASTRONOMIE - ECOLE NORM FRANCE 33-44 32 33 47 ------------------------------------------------------------------------------------ 7. Abstract IRAS images of nearby molecular clouds show that the mid-IR (12 and 25um) emission, supposed to come from small particules, is distributed very differently from the 100 um emission from large grains. These variations in the IR colors probably result from variations in the abundance of the small particules. We have performed observations of clouds of different colors ("blue" and "red") in the Chamaeleon at sub-mm, visible and UV wavelengths. They show that the variations in the IR colors are accompa nied by variations in the extinction curve, in the abundance of molecules (CO, CH+), as well as in temperature and density. The observation with the GHRS of several atomic and molecular absorption lines in the spectra of stars located behind both red and blue clouds will give access to important information on the clouds : H column densities from the lines of SII, depletion processes from the Si abundance, density and temperature from lines of the different CO rotation levels, pressure independently from lines of different CI excitation levels, cooling rates and heating processes in cold and warm phases from respectively CII and OI excited levels... All these quantities compared with our models will in addition to the study of the color variations and their implications, constitute a valuable data base to understand the physics and chemistry of these molecular clouds. ------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------ 9. Est obs time (hours) pri: 6.70 par: 0 10. Num targs pri: 2 par: 0 ------------------------------------------------------------------------------------ 11. Instruments requested: HRS ------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------ Page 2 I. GENERAL FORM Proposal 3759c PI: Francois Boulanger Proposal Title: DUST, MOLECULAR, ATOMIC COMPOSITION AND THE PHYSICAL CONDITIONS IN MOLECULAR CLOUDS ------------------------------------------------------------------------------------ 1. Proposers: Proposers Institution Country ESA ------------------------------------------------------------------------------------ Pi Francois Boulanger RADIOASTRONOMIE - ECOLE NORMALE FRANCE X SUPERIEURE Cecile Gry LABORATOIRE D'ASTRONOMIE FRANCE X SPATIALE James Lequeux OBSERVATOIRE DE PARIS-MEUDON FRANCE X Edith Falgarone RADIOASTRONOMIE - ECOLE NORMALE FRANCE X SUPERIEURE ------------------------------------------------------------------------------------ 2. Scientific Justification. ------------------------------------------------------------------------------------ 3. Description of proposed observations. We will record the spectrum of 2 stars at three spectral settings of the G160M grating. The three center wavelengths are 1265, 1338 and 1462 A. This should provide measurements of the following lines: CI (1216, 1280, and 1329 A) and CII (1355 A) OI (1355 A) CO (1447 and 1477 A) SII (1252 and 1258 A) To get the highest spectral resolution we will observe with the small aperture (SSA) and proceed by substepping the spectrum across the detector in 1/4-diode steps and then combining the four spectra into an oversampled spectrum, as it is described by R. Gilliland in the STScI Newsletter, June 1991. To correct for the photocathode granularity we will break down the exposure into 4 sub-exposures via the FP-split procedure. ------------------------------------------------------------------------------------ 4. Justification of need for HST observations. These observations (high resolution-spectroscopy in the Far-UV) can only be done with the GHRS on board the HST. Attempts for using IUE have been very disappointing for lack of resolution and signal to noise ratio. IUE spectra were used to plan these observations, showing us qualitatively which were the most interesting features in the spectra to characterize the two kinds of clouds. IUE low resolution spectra were used to derive the extinction curve for a larger sample of stars. We also high resolution optical spectra to measure the abundance of several molecular and atomic species. ------------------------------------------------------------------------------------ 5. Description of special scheduling requirements. None ------------------------------------------------------------------------------------ 6. Description of special calibration exposures. None ------------------------------------------------------------------------------------ 7. Data reduction and analysis plans. We will get from the ST ScI the calibrated science data which is provided as the output of the Routine Science Data Processing (RSDP) and Calibration Data Base Software (CDBS) at the Institut. The data reduction can be made at any of the proposing institutes which possess adequate facilities, with the help if necessary of the ESA ST/ECF in Garching. The data analysis will be done using an interactive program for line-profile fitting of which we have a considerable experience. ------------------------------------------------------------------------------------ 8. Additional comments or special requests. None Page 3 ------------------------------------------------------------------------------------ 9. Description of previous HST work. P 2078 "A search for primordial gas; is IZw18 a young galaxy?" PI J. Lequeux Not related to present project Observations not yet done no publication yet (see above) ------------------------------------------------------------------------------------ 10. Resources to be supplied by investigator's institution(s). All resources to be provided by the proposer's institutes One student will be dedicated to the project. ------------------------------------------------------------------------------------ 11. Address Information Name: FRANCOIS BOULANGER Category: PI Institution: RADIOASTRONOMIE - ECOLE NORMALE S Address: 24 RUE LHOMOND City: 75005 PARIS State: Zip Code: Country: FRANCE Telephone: (33) 1 44 32 33 47 Telex (or e-mail): ------------------------------------------------------------------------------------ TARGET LIST a) Fixed Targets ID = 3759c [ 4] ------------------------------------------------------------------------------------------------------------------------------------ 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial |Acqui|FLX| Flux data No | Name | Description | Position |Eqnx | Vel. |Prblm|REF| | | | | | | | | ------------------------------------------------------------------------------------------------------------------------------------ 1 HD96675 A,112,G,513 RA=11H 05M 58.17S +/-.05S, 2000 V = +0 1 V=7.65 +/-.01 DEC=-76D 07' 49." +/-.5" 2 B-V=+0.184 +/- .006 3 E(B-V)=0.31 +/- 0.03 4 F-CONT(1265)=5.0 +/-.5 E-11 5 F-CONT(1338)=6.0 +/-.5 E-11 6 F-CONT(1462)=7.0 +/-.5 E-11 Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) B 1950.00 -0.0015 +/- 0.0000 -0.0060 +/- 0.0000 0.0000 +/- 0.0000 ------------------------------------------------------------------------------------------------------------------------------------ 2 HD102065 A,112,G,513 RA=11H 43M 37.87S +/-.05S, 2000 V = +0 1 V=6.567 +/-.008 DEC=-80D 28' 59.4" +/-.5" 2 B-V=+0.106 +/- .006 3 E(B-V)=0.17 +/- 0.04 4 F-CONT(1265)=1.0 +/-.1 E-11 5 F-CONT(1338)=1.3 +/-.13 E-11 6 F-CONT(1462)=1.6 +/-.16 E-11 Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) B 1950.00 -0.0017 +/- 0.0000 -0.0030 +/- 0.0000 0.0000 +/- 0.0000 ------------------------------------------------------------------------------------------------------------------------------------ EXPOSURE LOGSHEET ID = 3759c [ 5] ------------------------------------------------------------------------------------------------------------------------------------ 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 |10 | 11 | 12 |13 |14| 15 ------------------------------------------------------------------------------------------------------------------------------------ Line | Seq | Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | S/N |Flx|Pr| Special Number | Name | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| |Rel. Time|Ref| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 1.1 HD96675 HRS ACQ 2.0 MIRROR-N2 SEARCH-SIZE=3 1.8S 1 ONBOARD ACQ FOR BRIGHT=RETURN 1.2-1.4 LOCATE=DEF CYCLE 2 / 1.1-2.4 ------------------------------------------------------------------------------------------------------------------------------------ 1.2 HD96675 HRS ACCUM 0.25 G160M 1265 STEP-PATT=5 4 17.5M 50 4 1 CYCLE 2 FP-SPLIT=STD COMB=FOUR DOPPLER=ON ------------------------------------------------------------------------------------------------------------------------------------ 1.3 HD96675 HRS ACCUM 0.25 G160M 1338 STEP-PATT=5 4 17.5M 60 5 1 CYCLE 2 FP-SPLIT=STD COMB=FOUR DOPPLER=ON ------------------------------------------------------------------------------------------------------------------------------------ 1.4 HD96675 HRS ACCUM 0.25 G160M 1462 STEP-PATT=5 8 17.5M 85 6 1 CYCLE 2 FP-SPLIT=STD COMB=FOUR DOPPLER=ON ------------------------------------------------------------------------------------------------------------------------------------ 2.1 HD102065 HRS ACQ 2.0 MIRROR-A2 SEARCH-SIZE=3 3.6S 1 ONBOARD ACQ FOR BRIGHT=RETURN 2.2-2.4 LOCATE=DEF CYCLE 2 / 1.1-2.4 ------------------------------------------------------------------------------------------------------------------------------------ 2.2 HD102065 HRS ACCUM 0.25 G160M 1265 STEP-PATT=5 3 11.7M 50 4 1 CYCLE 2 FP-SPLIT=STD COMB=FOUR DOPPLER=ON ------------------------------------------------------------------------------------------------------------------------------------ 2.3 HD102065 HRS ACCUM 0.25 G160M 1338 STEP-PATT=5 3 11.7M 60 5 1 CYCLE 2 FP-SPLIT=STD COMB=FOUR DOPPLER=ON ------------------------------------------------------------------------------------------------------------------------------------ 2.4 HD102065 HRS ACCUM 0.25 G160M 1462 STEP-PATT=5 4 17.5M 88 6 1 CYCLE 2 FP-SPLIT=STD COMB=FOUR DOPPLER=ON ------------------------------------------------------------------------------------------------------------------------------------ Summary Form for Proposal 3759c [ 6] Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations HRS ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACQ ACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters SEARCH-SIZE=3 BRIGHT=RETURN LOCATE=DEF STEP-PATT=5 FP-SPLIT=STD COMB=FOUR DOPPLER=ON ------------------------------------------------------------------------------------------------------------------------------------ Proposal for GO ------------------------------------------------------------------------------------------------------------------------------------ S/C Hours 6.70 ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category INTERSTELLAR MEDIUM ------------------------------------------------------------------------------------------------------------------------------------ Scientific Sub-category DUST ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ONBOARD ACQ FOR 1.2-1.4; CYCLE 2 / 1.1-2.4; CYCLE 2; ONBOARD ACQ FOR 2.2-2.4; CYCLE 2 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements MIRROR-N2 G160M MIRROR-A2 ------------------------------------------------------------------------------------------------------------------------------------ Target Names HD96675 HD102065 ------------------------------------------------------------------------------------------------------------------------------------