! +====================+ ! | PED OUTPUT PRODUCT | ! +====================+ ! ! /spectre/data1/aroman/proposals/6034.prop ! Generated by PREPROCESSOR, version 6.0e ! Date: Tue Dec 12 10:26:17 EST 1995 Proposal_Information Title: Physical conditions in ionized--neutral interfaces Proposal_Category: GO Scientific_Category: Interstellar Medium Cycle: 5 Investigators PI_Name: Jeremy Walsh PI_Institution: Space Telescope European Co-ordinating Facility CoI_Name: Michael Rosa CoI_Institution: Space Telescope European Coordinating Facility Contact: CoI_Name: Och Susanne CoI_Institution: European Southern Observatory Contact: Abstract: High spatial resolution FOS spectra of the emission lines from ionized-neutral gas interfaces are proposed covering the UV- visible wavelength range. One partially ionized globule and one dense filament will be selected in the core of the nearest H II region, the Orion nebula. Spectra representing pencil beams with spatial resolution of 0.25" will be obtained at several positions across each target: centered on the condensation; at the edge in the very thin interface zone facing the ionizing cluster; in the tail behind the condensation and also in locations representative of the ionized surroundings. Emission line ratios so observed will be compared to dedicated nebular models treating, in detail and self-consistently, H II regions with neutral inclusions of arbitrary geometry, in order to derive the small-scale structure of the physical conditions -- N_e, T_e, ioniation parameter, fraction of neutral H, etc. Radiative transfer effects on the ionization of the shadowed zone by diffuse radiation, line of sight averaging of high and low ionization regimes to produce the integrated spectra of real nebulae and the time evolution of neutral inclusions will be among the topics studied on the basis of these observations. Questions Observing_Description: The FOS Red side will be used with the five high dispersion gratings (G190H, G270H, G400H, G570H and G780H) covering the UV and optical region of the spectrum (1600-8300 A) to measure the strength of emission lines over and in the near vicinity of neutral inclusions in the Orion nebula. The aperture B-2 aperture (projected diameter 0.26") will be employed to achieve high spatial resolution to ensure as little contamination as possible from neighbouring emission. Two targets will be observed: one of the Laques & Vidal (1979) partially ionized globules in the vicinity of the Trapezium stars (No. 2, referred to as LV2) and one of the S II strong filaments selected from the HST images of Orion. For the LV globule, spectra will be obtained at the bright ionization margin, at the centre of the globule, and in the tail of the globule. For the filament, spectra will be obtained on the filament ridge as seen in NII and at a position nearby representative of the average nebular background for that filament. The spectra off the targets are required to determine the background contribution to the targets and an indication of the small scale changes in emission line properties against which the neutral-ionized interface spectra must be compared. Employing the 0.26" aperture on the WFPC2 ERO images (u2440101t-u2440104t), combined with the flux measurements of Meaburn et al (1993), and scaling by the mean line ratios of the Orion emission line spectrum near the Trapezium region (Pos. 2b of Peimbert & Torres-Peimbert, MNRAS 179, 217 (1977), Pos 2uv of Torres-Peimbert+, APJ 238, 133 (1980)) gives the following estimated HAlfa line fluxes and detected counts in the aperture: Position F(HAlfa) Detected Cnts/s G570H LV2 core 3.0E-13 100 LV2 head 2.9E-13 100 LV2 tail 2.8E-13 95 Filament 2.6E-13 90 Near filament 2.0E-13 68 For the weak line diagnostics we need to go to at least as faint as the OIII 4363 A line, i.e. 0.0017 of HAlfa. For accurate T_e determination we need an SNR of better 10 for that strengths, so >=100 counts. This implies 200-1000s per wavelength range for G400H and G570H, 100-200s for the UV gratings (for the important C II and C III lines), and 50-100s for the less sensitive G780H grating. The G780H range has the important O II 7320,7330 A line as well as HAlpha, N II 6548,6583 A, and SII 6718,6730 A lines. Thus between 500s and 2000s are required per position, depending on the anticipated ionization conditions. The 6 orbits allocated permit a total of 5600s science exposure distributed among 5 positions. The initial PhaseI request asked for a total 48000s to to do 5 positions on LV2 and 3 on the filament. Figure caption: HAlpha plate showing the Lacques--Vidal sources near the Trapezium cluster (Vidal 1982, in Symposium on the Orion Nebula to honor Henry Draper, Glassgold et al (eds), Ann. NY Acad. Sci. Vol 395, p 176). South is up and East is to the right. Exact positions of the positions across the targets and the required offsets from a nearby faint star, which will be used for centering with peakup acquisition, have been determined from public WFPC2 data sets. Real_Time_Justification: Calibration_Justification: Additional_Comments: Fixed_Targets Target_Number: 1 Target_Name: M42-OFFSET-STAR Alternate_Names: PARENAGO 538 Description: STAR Position: RA=05H 35M 17.010S +/- 0.02S,DEC=-05D 23' 34.32" +/- 0.3" Equinox: 2000 RV_or_Z: RA_PM: 0.0 Dec_PM: 0.0 Epoch: 1994.2 Annual_Parallax: 0.0 Flux: V = 14.8 B-V = 0.30 Comments: Offset star for peak-up and offsets to targets. Vmag and position from WFPC2 u2440103t[4] (NEW PLATE SCALE=0.04554), color unknown, assumed F0 type. Revised coordinates correspond to average of zeroing the frame on SAO pos of THETA1C, the catalogue position Jones/Walker AJ 95,1755 (1988), and direct measurement on WFPC1 frame W0O70A01T. Target_Number: 2 Target_Name: M42-LV2-CORE Alternate_Names: LACQUES-VIDAL GLOBULE 2 (CORE) Description: ISM, KNOT Position: RA-OFF=-0.301S+/- 0.002S,DEC-OFF=17.70"+/- 0.03",FROM 1 Equinox: 2000 RV_or_Z: RA_PM: 0.0 Dec_PM: 0.0 Epoch: 1994.2 Annual_Parallax: 0.0 Flux: SURF-LINE(6563)=6.0+/-0.5e-12 Comments: Peak of Lacques-Vidal Globule 2. Offset measured from WFPC2 u2440103t[4]. Target_Number: 3 Target_Name: M42-LV2-TAIL Alternate_Names: LACQUES-VIDAL GLOBULE 2 (TAIL) Description: ISM, KNOT Position: RA-OFF=-0.272S+/- 0.002S,DEC-OFF=18.35"+/- 0.03",FROM 1 Equinox: 2000 RV_or_Z: RA_PM: 0.0 Dec_PM: 0.0 Epoch: 1994.2 Annual_Parallax: 0.0 Flux: SURF-LINE(6563)=5.8+/-0.5e-12 Comments: 1.0" NW from peak of Lacques-Vidal Globule 2. Offset measured from WFPC2 u2440103t[4]. Target_Number: 4 Target_Name: M42-LV2-HEAD Alternate_Names: LACQUES-VIDAL GLOBULE 2 (HEAD) Description: ISM, KNOT Position: RA-OFF=-.315S+/- 0.002S,DEC-OFF=17.39"+/- 0.03",FROM 1 Equinox: 2000 RV_or_Z: RA_PM: 0.0 Dec_PM: 0.0 Epoch: 1994.2 Annual_Parallax: 0.0 Flux: SURF-LINE(6563)=5.7+/-0.5e-12 Comments: .6" SE from peak of Lacques-Vidal Globule 2. Offset measured from WFPC2 u2440103t[4]. Target_Number: 5 Target_Name: M42-FILAMENT-PEAK Alternate_Names: Description: ISM, FILAMENT Position: RA-OFF=-0.938S+/- 0.002S,DEC-OFF=-35.95"+/- 0.03",FROM 1 Equinox: 2000 RV_or_Z: RA_PM: 0.0 Dec_PM: 0.0 Epoch: 1994.2 Annual_Parallax: 0.0 Flux: SURF-LINE(6563)=5.2+/-0.5e-12 Comments: Local peak of narrow filament in core of M42. Offset measured from WFPC2 u2440103t[4]. Target_Number: 6 Target_Name: M42-FILAMENT-BACK Alternate_Names: Description: ISM, FILAMENT Position: RA-OFF=-0.837S+/- 0.002S,DEC-OFF=-35.60"+/- 0.03",FROM 1 Equinox: 2000 RV_or_Z: RA_PM: 0.0 Dec_PM: 0.0 Epoch: 1994.2 Annual_Parallax: 0.0 Flux: SURF-LINE(6563)=4.1+/-0.5e-12 Comments: Background position 1.5" E of filament. Offset measured from WFPC2 u2440103t[4]. Solar_System_Targets Generic_Targets Scan_Data Visits Visit_Number: 01 Visit_Requirements: ON HOLD On_Hold_Comments: Position of TARGET 1 (offset star) to be checked, since it is obtained as offset from overexposed star THET1 ORIC on WFPC2. THET1 ORIC is also in GSC but has uncertain position due to overexposure. Discrepancies WFPC2-GSC-SAO-PPM amount to several arcseconds. To be resolved till April 1995. Offset star is likely in Orion cluster catalog (Parenago). Visit_Comments: Exposure_Number: 1 Target_Name: M42-OFFSET-STAR Config: FOS/RD Opmode: ACQ/PEAK Aperture: 4.3 Sp_Element: MIRROR Wavelength: Optional_Parameters: SCAN-STEP-X=2.3,SCAN-STEP-Y=1.2,SEARCH-SIZE-X=2,SEARCH-SIZE-Y=5 Number_of_Iterations: 1 Time_Per_Exposure: 1S Special_Requirements: ONBOARD ACQ FOR 2 Comments: Exposure_Number: 2 Target_Name: M42-OFFSET-STAR Config: FOS/RD Opmode: ACQ/PEAK Aperture: 1.0 Sp_Element: MIRROR Wavelength: Optional_Parameters: SCAN-STEP-X=0.61,SCAN-STEP-Y=0.61,SEARCH-SIZE-X=6,SEARCH-SIZE-Y=2 Number_of_Iterations: 1 Time_Per_Exposure: 1S Special_Requirements: ONBOARD ACQ FOR 3 Comments: Exposure_Number: 3 Target_Name: M42-OFFSET-STAR Config: FOS/RD Opmode: ACQ/PEAK Aperture: 0.5 Sp_Element: MIRROR Wavelength: Optional_Parameters: SCAN-STEP-X=0.29,SCAN-STEP-Y=0.29,SEARCH-SIZE-X=3,SEARCH-SIZE-Y=3 Number_of_Iterations: 1 Time_Per_Exposure: 1S Special_Requirements: ONBOARD ACQ FOR 4 Comments: Exposure_Number: 4 Target_Name: M42-OFFSET-STAR Config: FOS/RD Opmode: ACQ/PEAK Aperture: 0.3 Sp_Element: MIRROR Wavelength: Optional_Parameters: SCAN-STEP-X=0.11,SCAN-STEP-Y=0.11,SEARCH-SIZE-X=4,SEARCH-SIZE-Y=4 Number_of_Iterations: 1 Time_Per_Exposure: 3S Special_Requirements: ONBOARD ACQ FOR 10-54 Comments: Exposure_Number: 10 Target_Name: M42-LV2-CORE Config: FOS/RD Opmode: ACCUM Aperture: 0.3 Sp_Element: G190H Wavelength: Optional_Parameters: Number_of_Iterations: 1 Time_Per_Exposure: 60S Special_Requirements: Comments: Exposure_Number: 11 Target_Name: M42-LV2-CORE Config: FOS/RD Opmode: ACCUM Aperture: 0.3 Sp_Element: G270H Wavelength: Optional_Parameters: Number_of_Iterations: 1 Time_Per_Exposure: 40S Special_Requirements: Comments: Exposure_Number: 12 Target_Name: M42-LV2-CORE Config: FOS/RD Opmode: ACCUM Aperture: 0.3 Sp_Element: G400H Wavelength: Optional_Parameters: Number_of_Iterations: 1 Time_Per_Exposure: 200S Special_Requirements: Comments: Exposure_Number: 13 Target_Name: M42-LV2-CORE Config: FOS/RD Opmode: ACCUM Aperture: 0.3 Sp_Element: G570H Wavelength: Optional_Parameters: Number_of_Iterations: 1 Time_Per_Exposure: 200S Special_Requirements: Comments: Exposure_Number: 14 Target_Name: M42-LV2-CORE Config: FOS/RD Opmode: ACCUM Aperture: 0.3 Sp_Element: G780H Wavelength: Optional_Parameters: Number_of_Iterations: 1 Time_Per_Exposure: 60S Special_Requirements: Comments: Exposure_Number: 20 Target_Name: M42-LV2-TAIL Config: FOS/RD Opmode: ACCUM Aperture: 0.3 Sp_Element: G190H Wavelength: Optional_Parameters: Number_of_Iterations: 1 Time_Per_Exposure: 60S Special_Requirements: Comments: Exposure_Number: 21 Target_Name: M42-LV2-TAIL Config: FOS/RD Opmode: ACCUM Aperture: 0.3 Sp_Element: G270H Wavelength: Optional_Parameters: Number_of_Iterations: 1 Time_Per_Exposure: 30S Special_Requirements: Comments: Exposure_Number: 22 Target_Name: M42-LV2-TAIL Config: FOS/RD Opmode: ACCUM Aperture: 0.3 Sp_Element: G400H Wavelength: Optional_Parameters: Number_of_Iterations: 1 Time_Per_Exposure: 230S Special_Requirements: Comments: Exposure_Number: 23 Target_Name: M42-LV2-TAIL Config: FOS/RD Opmode: ACCUM Aperture: 0.3 Sp_Element: G570H Wavelength: Optional_Parameters: Number_of_Iterations: 1 Time_Per_Exposure: 229S Special_Requirements: Comments: Exposure_Number: 24 Target_Name: M42-LV2-TAIL Config: FOS/RD Opmode: ACCUM Aperture: 0.3 Sp_Element: G780H Wavelength: Optional_Parameters: Number_of_Iterations: 1 Time_Per_Exposure: 100S Special_Requirements: Comments: Exposure_Number: 30 Target_Name: M42-LV2-HEAD Config: FOS/RD Opmode: ACCUM Aperture: 0.3 Sp_Element: G190H Wavelength: Optional_Parameters: Number_of_Iterations: 1 Time_Per_Exposure: 100S Special_Requirements: Comments: Exposure_Number: 31 Target_Name: M42-LV2-HEAD Config: FOS/RD Opmode: ACCUM Aperture: 0.3 Sp_Element: G270H Wavelength: Optional_Parameters: Number_of_Iterations: 1 Time_Per_Exposure: 80S Special_Requirements: Comments: Exposure_Number: 32 Target_Name: M42-LV2-HEAD Config: FOS/RD Opmode: ACCUM Aperture: 0.3 Sp_Element: G400H Wavelength: Optional_Parameters: Number_of_Iterations: 1 Time_Per_Exposure: 220S Special_Requirements: Comments: Exposure_Number: 33 Target_Name: M42-LV2-HEAD Config: FOS/RD Opmode: ACCUM Aperture: 0.3 Sp_Element: G570H Wavelength: Optional_Parameters: Number_of_Iterations: 1 Time_Per_Exposure: 200S Special_Requirements: Comments: Exposure_Number: 34 Target_Name: M42-LV2-HEAD Config: FOS/RD Opmode: ACCUM Aperture: 0.3 Sp_Element: G780H Wavelength: Optional_Parameters: Number_of_Iterations: 1 Time_Per_Exposure: 80S Special_Requirements: Comments: Exposure_Number: 40 Target_Name: M42-FILAMENT-PEAK Config: FOS/RD Opmode: ACCUM Aperture: 0.3 Sp_Element: G190H Wavelength: Optional_Parameters: Number_of_Iterations: 1 Time_Per_Exposure: 200S Special_Requirements: Comments: Exposure_Number: 41 Target_Name: M42-FILAMENT-PEAK Config: FOS/RD Opmode: ACCUM Aperture: 0.3 Sp_Element: G270H Wavelength: Optional_Parameters: Number_of_Iterations: 1 Time_Per_Exposure: 85S Special_Requirements: Comments: Exposure_Number: 42 Target_Name: M42-FILAMENT-PEAK Config: FOS/RD Opmode: ACCUM Aperture: 0.3 Sp_Element: G400H Wavelength: Optional_Parameters: Number_of_Iterations: 1 Time_Per_Exposure: 666S Special_Requirements: Comments: Exposure_Number: 43 Target_Name: M42-FILAMENT-PEAK Config: FOS/RD Opmode: ACCUM Aperture: 0.3 Sp_Element: G570H Wavelength: Optional_Parameters: Number_of_Iterations: 1 Time_Per_Exposure: 1000S Special_Requirements: Comments: Exposure_Number: 44 Target_Name: M42-FILAMENT-PEAK Config: FOS/RD Opmode: ACCUM Aperture: 0.3 Sp_Element: G780H Wavelength: Optional_Parameters: Number_of_Iterations: 1 Time_Per_Exposure: 100S Special_Requirements: Comments: Exposure_Number: 50 Target_Name: M42-FILAMENT-BACK Config: FOS/RD Opmode: ACCUM Aperture: 0.3 Sp_Element: G190H Wavelength: Optional_Parameters: Number_of_Iterations: 1 Time_Per_Exposure: 200S Special_Requirements: Comments: Exposure_Number: 51 Target_Name: M42-FILAMENT-BACK Config: FOS/RD Opmode: ACCUM Aperture: 0.3 Sp_Element: G270H Wavelength: Optional_Parameters: Number_of_Iterations: 1 Time_Per_Exposure: 58S Special_Requirements: Comments: Exposure_Number: 52 Target_Name: M42-FILAMENT-BACK Config: FOS/RD Opmode: ACCUM Aperture: 0.3 Sp_Element: G400H Wavelength: Optional_Parameters: Number_of_Iterations: 1 Time_Per_Exposure: 666S Special_Requirements: Comments: Exposure_Number: 53 Target_Name: M42-FILAMENT-BACK Config: FOS/RD Opmode: ACCUM Aperture: 0.3 Sp_Element: G570H Wavelength: Optional_Parameters: Number_of_Iterations: 1 Time_Per_Exposure: 1000S Special_Requirements: Comments: Exposure_Number: 54 Target_Name: M42-FILAMENT-BACK Config: FOS/RD Opmode: ACCUM Aperture: 0.3 Sp_Element: G780H Wavelength: Optional_Parameters: Number_of_Iterations: 1 Time_Per_Exposure: 100S Special_Requirements: Comments: Data_Distribution ! Defaults indicated; change if desired Medium: 8MM Blocking_Factor: 10 Ship_To: PI_address Ship_Via: UPS Recipient_Email: ! Let us know what you think of this template and software! ! Please send a list of your likes and dislikes to your Program Coordinator