Page 1 PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID 3746c Report Date: 09-May-96:18:49 Version: ********** Check-in Date: ********** 1.Proposal Title: THE COOLING OF THE LOCAL DIFFUSE INTERSTELLAR MEDIUM ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Proposal Type 5. Continuation ID INTERSTELLAR MEDIUM GO Sub Category LOCAL MEDIUM ------------------------------------------------------------------------------------ 6. Principal Investigator Institution Country Telephone Cecile Gry LABORATOIRE D'ASTRONOMIE SPA FRANCE 33-91-055927 ------------------------------------------------------------------------------------ 7. Abstract We want to study the cooling processes of the local interstellar medium by observing the population of the excited fine-structure states in the ground electronic level of ionized carbon and neutral atomic oxygen. Far-IR line emission between these excited states and the ground states of these ions is the main cooling agent of the cold and warm neutral atomic gas respectively. The corresponding column densities in front of bright stars will be obtained from GHRS observations of electronic transitions originating from these states. In order to study the structure of the interstellar matter along the lines of sight, other transitions will be observed with the GHRS and from the ground: this is necessary to correctly derive the column densities of the different individual components by fitting the lines with theoretical profiles and to separate the neutral from the ionized medium along the lines of sight. A comparison of the results with direct observations of the FIR fine -structure lines from COBE and later from ISO and SIRTF will allow to determine to what extent the local interstellar medium is representative of the general medium at galactic scales, and in particular to compare the far-UV interstellar radiation fields. ------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------ 9. Est obs time (hours) pri: 7.22 par: 0 10. Num targs pri: 18 par: 0 ------------------------------------------------------------------------------------ 11. Instruments requested: HRS ------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------ Page 2 I. GENERAL FORM Proposal 3746c PI: Cecile Gry Proposal Title: THE COOLING OF THE LOCAL DIFFUSE INTERSTELLAR MEDIUM ------------------------------------------------------------------------------------ 1. Proposers: Proposers Institution Country ESA ------------------------------------------------------------------------------------ Pi Cecile Gry LABORATOIRE D'ASTRONOMIE FRANCE X SPATIALE Francois Boulanger OBSERVATOIRE DE PARIS-MEUDON FRANCE X James Lequeux OBSERVATOIRE DE PARIS-MEUDON FRANCE X ------------------------------------------------------------------------------------ 2. Scientific Justification. ------------------------------------------------------------------------------------ 3. Description of proposed observations. We will record the spectrum of 8 stars at one spectral setting of the G160M grating. It will be centered at the wavelength of 1312 A to optimize both the quality of the photocathode at the most important line (OI* 1304A) and the number of covered interesting spectral lines. Special care will be taken to get i) the highest possible resolution : the spectra will be recorded in the SSA with a substepping of 4, to increase the resolution by deconvolution. ii) a very high signal to noise ratio. To overcome the limit due to the photocathode granularity, we will break down the exposure into 4 subexposures via the FP-split procedure to distinguish between photocathode granularity and spectral features, and we aim at getting a photon noise much smaller than the fixed-pattern noise (>2%) therefore we calculate the exposure time corresponding to a S/N of 250 for each diode substep (i.e. the total exposure time for one target will be 4 times this time). ------------------------------------------------------------------------------------ 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. Copernicus data have been used in a preliminary study for CII*, NII* and NII**, but a better S/N ratio is needed to detect OI*. Nevertheless ground-based observations will be performed to help defining the line of sight structure. ------------------------------------------------------------------------------------ 5. Description of special scheduling requirements. For the faint OI* and OI** lines, there is a possibility of contamination by telluric lines (In the Xi Per spectrum presented by Savage in the STScI Newsletter of March 1991, the telluric OI* is very well seen). We thus ask to make those observations when the velocity shift between the earth and the interstellar cloud is not null (higher than 10 km/s). The allowed observation dates are specified are requirements.Usually there are two allowed time intervals in one year. ------------------------------------------------------------------------------------ 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. Page 3 ------------------------------------------------------------------------------------ 8. Additional comments or special requests. None ------------------------------------------------------------------------------------ 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 At least one student will be dedicated to the project. ------------------------------------------------------------------------------------ 11. Address Information Name: CECILE GRY Category: PI Institution: LABORATOIRE D'ASTRONOMIE SPATIALE Address: TRAVERSE DU SIPHON LES TROIS LUCS City: 13012 MARSEILLE State: Zip Code: Country: FRANCE Telephone: (33) 91 05 59 27 Telex (or e-mail): 420 584 ASTROSP F ------------------------------------------------------------------------------------ TARGET LIST a) Fixed Targets ID = 3746c [ 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 HD149038 MU- A,105,G,513 RA=16H 34M 04.86S +/-.05S, 2000 V = +5 1 V=4.87 +/-.1 NOR DEC=-44D 02' 42.8" +/-.1" 2 B-V=+0.10 +/- .02 3 F-CONT(1300)=5.0 +/-.3 E-10 Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) B 1950.00 -0.0007 +/- 0.0000 -0.0050 +/- 0.0000 0.0000 +/- 0.0000 ------------------------------------------------------------------------------------------------------------------------------------ 2 HD149757 ZET A,104,G,513 RA=16H 37M 09.398S +/-.01S, 2000 V = -15 1 V = 2.57 +/-.1 -OPH DEC=-10D 34' 02.79" +/-.1" 2 B-V = +0.02 +/- .02 3 F-CONT(1300) = 4.0 +/-.3 E-9 Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) B 1950.00 0.0008 +/- 0.0000 0.0230 +/- 0.0000 0.0000 +/- 0.0000 ------------------------------------------------------------------------------------------------------------------------------------ 3 HD30614 ALP- A,105,G,513 RA = 04H 54M 02.966S +/- 2000 V = +6.1 1 V = 4.29 +/-.01 CAM .01S, 2 B-V = +0.04 +/- .01 DEC = +66D 20' 33.45" +/- 3 F-CONT(1300) = 6.9 +/-.1 E-10 .1" Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) B 1950.00 -0.0003 +/- 0.0000 0.0290 +/- 0.0000 0.0000 +/- 0.0000 ------------------------------------------------------------------------------------------------------------------------------------ 4 HD165024 TET A,113,G,508 RA = 18H 06M 37.78S +/-.05S, 2000 V = +3.4 1 V = 3.66 +/-.01 -ARA DEC = -50D 05' 29.0" +/-.1" 2 B-V = -.09 +/- .01 3 F-CONT(1300) = 2.2 +/-.1 E-9 Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) B 1950.00 -0.0007 +/- 0.0000 -0.0170 +/- 0.0000 0.0000 +/- 0.0000 ------------------------------------------------------------------------------------------------------------------------------------ 5 HD214680 A,104,G,508 RA = 22H 39M 15.60S +/-.01S, 2000 V = -9.7 1 V = 4.90 +/-.02 10LAC DEC = 39D 03' 01.21" +/-.1" 2 B-V = -0.20 +/- .02 3 F-CONT(1300) = 2.4 +/-.3 E-9 Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) B 1950.00 -0.0021 +/- 0.0000 0.0290 +/- 0.0000 0.0050 +/- 0.0000 ------------------------------------------------------------------------------------------------------------------------------------ EXPOSURE LOGSHEET ID = 3746c [ 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 HD149038 HRS ACQ 2.0 MIRROR-A2 SEARCH-SIZE=3 1.8S 1 ONBOARD ACQ FOR BRIGHT=65000 1.2 FAINT=1000 AT 4-SEP-92 +/- LOCATE=DEF 62D CYCLE 2 / 1.1-8.2 Comments: AVOID OBSERVING WHEN THE EARTH HAS SAME RADIAL VELOCITY AS THE INTERSTELLAR CLOUD. ALLOWED PERIODS : DEC 19 TO MAY 22 OR : JULY 4 TO NOV 5 ALTERNATE AT 6- MAR-93 +/- 77D ------------------------------------------------------------------------------------------------------------------------------------ 1.2 HD149038 HRS ACCUM 0.25 G160M 1312 STEP-PATT=5 3 13.3M 200 3 1 FP-SPLIT=STD COMB=FOUR DOPPLER=ON ------------------------------------------------------------------------------------------------------------------------------------ 2.1 HD149757 HRS ACQ 2.0 MIRROR-A2 SEARCH-SIZE=3 1.8S 1 ONBOARD ACQ FOR BRIGHT=65000 2.2 FAINT=2000 AT 1-SEP-92 +/- LOCATE=DEF 36D Comments: AVOID OBSERVING WHEN THE EARTH HAS SAME RADIAL VELOCITY AS THE INTERSTELLAR CLOUD. ALLOWED PERIODS : NOV 25 TO JUNE 10 OR : JULY 27 TO OCT 7 ALTERNATE AT 3-MAR-93 +/- 98D; ------------------------------------------------------------------------------------------------------------------------------------ 2.2 HD149757 HRS ACCUM 0.25 G160M 1312 STEP-PATT=5 1 7M 250 3 1 FP-SPLIT=STD COMB=FOUR DOPPLER=ON ------------------------------------------------------------------------------------------------------------------------------------ 3.1 HD30614 HRS ACQ 2.0 MIRROR-A2 SEARCH-SIZE=3 1.8S 1 ONBOARD ACQ FOR BRIGHT=65000 3.2 FAINT=1000 AT 13-SEP-92 +/- LOCATE=DEF 73D Comments: AVOID OBSERVING WHEN THE EARTH HAS SAME RADIAL VELOCITY AS THE INTERSTELLAR CLOUD. ALLOWED PERIODS : JAN 14 TO MAY 9 OR : JULY 2 TO NOV 26 ALTERNATE AT 12-MAR-93 +/- 57D ------------------------------------------------------------------------------------------------------------------------------------ 3.2 HD30614 HRS ACCUM 0.25 G160M 1312 STEP-PATT=5 2 15M 250 3 1 FP-SPLIT=STD COMB=FOUR DOPPLER=ON ------------------------------------------------------------------------------------------------------------------------------------ EXPOSURE LOGSHEET ID = 3746c [ 6] ------------------------------------------------------------------------------------------------------------------------------------ 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 ------------------------------------------------------------------------------------------------------------------------------------ 4.1 HD165024 HRS ACQ 2.0 MIRROR-A2 SEARCH-SIZE=3 1.8S 1 ONBOARD ACQ FOR BRIGHT=65000 4.2 FAINT=1000 AT 21-SEP-92 +/- LOCATE=DEF 53D Comments: AVOID OBSERVING WHEN THE EARTH HAS SAME RADIAL VELOCITY AS THE INTERSTELLAR CLOUD. ALT AT:21- MAR-93 +/- 86D ALLOWED : JULY 30 TO NOVEMBER 13 OR: DECEMBER 25 TO JUNE 15 ------------------------------------------------------------------------------------------------------------------------------------ 4.2 HD165024 HRS ACCUM 0.25 G160M 1312 STEP-PATT=5 2 7M 250 3 1 FP-SPLIT=STD COMB=FOUR DOPPLER=ON ------------------------------------------------------------------------------------------------------------------------------------ 8.1 HD214680 HRS ACQ 2.0 MIRROR-A2 SEARCH-SIZE=3 1.8S 1 ONBOARD ACQ FOR BRIGHT=65000 8.2 FAINT=1000 AT 21-DEC-92 +/- LOCATE=DEF 100D Comments: AVOID OBSERVING WHEN THE EARTH HAS SAME RADIAL VELOCITY AS THE INTERSTELLAR CLOUD. ALLOWED PERIODS : SEP 10 TO APR 2 OR : MAY 4 TO AUG 9 ALTERNATE AT 21- JUN-93 +/- 48D ------------------------------------------------------------------------------------------------------------------------------------ 8.2 HD214680 HRS ACCUM 0.25 G160M 1312 STEP-PATT=5 2 7M 250 3 1 FP-SPLIT=STD COMB=FOUR DOPPLER=ON ------------------------------------------------------------------------------------------------------------------------------------ Summary Form for Proposal 3746c [ 7] Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations HRS ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACQ ACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters SEARCH-SIZE=3 BRIGHT=65000 FAINT=1000 LOCATE=DEF STEP-PATT=5 FP-SPLIT=STD COMB=FOUR DOPPLER=ON FAINT=2000 ------------------------------------------------------------------------------------------------------------------------------------ Proposal for GO ------------------------------------------------------------------------------------------------------------------------------------ S/C Hours 7.22 ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category INTERSTELLAR MEDIUM ------------------------------------------------------------------------------------------------------------------------------------ Scientific Sub-category LOCAL MEDIUM ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ONBOARD ACQ FOR 1.2; AT 4-SEP-92 +/- 62D; CYCLE 2 / 1.1-8.2; ONBOARD ACQ FOR 2.2; AT 1-SEP-92 +/- 36D; ONBOARD ACQ FOR 3.2; AT 13-SEP-92 +/- 73D; ONBOARD ACQ FOR 4.2; AT 21-SEP-92 +/- 53D; ONBOARD ACQ FOR 8.2; AT 21-DEC-92 +/- 100D; ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements MIRROR-A2 G160M ------------------------------------------------------------------------------------------------------------------------------------ Target Names HD149038 MU-NOR HD149757 ZET-OPH HD30614 ALP-CAM HD165024 TET-ARA HD214680 10LAC ------------------------------------------------------------------------------------------------------------------------------------