! Hubble Space Telescope Cycle 5 (1995) Phase II Proposal Template ! $Id: 6082,v 6.1 1995/09/28 17:02:51 pepsa Exp $ ! ! Refer to the HST Phase II Proposal Instructions to fill this out ! ! Anything after a "!" is ignored, and may be deleted ! ! All keywords with multiple entries are comma delimited except the ! Visit_Requirements and Special_Requirements keywords which can be ! delimited with carriage returns or semi-colons, but not commas ! ! For help call your Program Coordinator: Dustin Manning ! Phone: 410 338-4456 , E-mail: manning@stsci.edu ! ! This partially completed template was generated from a Phase I proposal. ! Date generated: Sun Dec 18 19:19:15 EST 1994 ! Proposal_Information ! Section 4 Title: GHRS Spatially Resolved Spectra of Nova Cygni 1992 Proposal_Category: GO Scientific_Category: Interstellar Medium Cycle: 5 Investigators PI_name: Steven Shore PI_Institution: Indiana University South Bend CoI_Name: Thomas Ake CoI_Institution: Computer Sciences Corp./GSFC Contact: ! Y or N (designate at most one contact) CoI_Name: Robert Gehrz CoI_Institution: University of Minnesota Contact: ! Y or N (designate at most one contact) CoI_Name: Rosario Gonzalez-Riestra CoI_Institution: European Space Agency/Vilspa Contact: ! Y or N (designate at most one contact) CoI_Name: Peter Hauschildt CoI_Institution: Arizona State University Contact: ! Y or N (designate at most one contact) CoI_Name: Joachim Krautter CoI_Institution: Landessternwarte-Heidelberg Contact: ! Y or N (designate at most one contact) CoI_Name: George Sonneborn CoI_Institution: NASA Goddard Space Flight Center Contact: ! Y or N (designate at most one contact) CoI_Name: Sumner Starrfield CoI_Institution: Arizona State University Contact: ! Y or N (designate at most one contact) Abstract: ! Free format text (please update) We willobtain spatially resolved low resolution, 120 km s^-1 GHRS small science aperture spectra of a UV emitting knot in the ejecta of the bright Galactic OMgNe nova Cygni 1992. With the good spectral resolution, FUV sensitivity, and photon counting capabilities of the GHRS and the SSA, we will study the structure and dynamics of the nova Cyg 1992 ejecta at an intermediate stage of its expansion, very soon after the turnoff of the central nuclear source. We will determine abundances for key species in the ejecta, especially neon. These observations will provide a detailed picture of physical conditions and abundances of the ejecta that has never before been available from UV spectra, including those taken before the COSTAR installation. The knots are likely the result of a Rayleigh- Taylor instability during the explosion, and the differential mixing that may have accompanied it can be studied using the knot spectra. We will also obtain an LSA G160M medium resolution (R=15000) spectrum of the spatially integrated He II 1640 line profile. Finally, we will also obtain moderate S/N LSA G140L low resolution observations of the UV continuum of the hot central star and high S/N spatially integrated line profile data for the nebula in order to study the physical conditions in the post-thermonuclear runaway envelope. Questions ! Free format text (please update) Observing_Description: begincenter Proposed Observations endcenter Low resolution G140L spectra (resolution 120 - 200 km s^-1) will be obtained for two settings, covering the region from 1200 - 1760 Angstrom, with a resolution of R=1500, for the central star with the LSA (which will include the nebula). One spectrum, centered at 1622 Angstrom, will be obtained for the brightest knot with the G140L and the SSA with the full resolution of 2500. In addition, we will obtain an LSA G160M spectrum at the central star with nebula at He II 1640,. The exposure times (15 min per G140L spectrum) provide S/N=20-40 at the peak of the emission lines and S/N=5-10 per resolution element in the stellar continuum. We will obtain spectra for the UV-brightest knot in the FOC images and a set of spectra pointing at the central star. We also propose to use the G140L grating to obtain two high S/N low resolution observations of the entire short wavelength spectrum in order to determine the flux distribution of the remnant's photosphere. We will require 65 minutes to obtain spectra with sufficient S/N to study the central star with settings at 1340Angstrom\ and 1518Angstrom\ to cover the continuum, especially the LyAlpha profile. Predicted exposures are based on our most recent IUE observation obtained on 1994 Nov. 22. The overall decrease in emission line intensity and decreased ionization fraction (based on the N III/N IV/N V strengths followed since the beginning of the optically thin stage in 1992 June) was used to predict the spectrum for a generic observation in 1995 Aug. We have used the observed power law decline, roughly t^-3, and the COSTAR SSA throughput to predict the count rates. The observations will use FP-SPLIT=2 and quarter-stepping to obtain the highest spectral resolution and highest S/N ratio. Astrometry will be obtained for the brightest knots from the pre- and post- COSTAR FOC images. Our preliminary assessment is based on ERO observations taken post-COSTAR and also on the published information about the 31 May 1993 UV image obtained with the FOC. Thus, we will not require a separate pre-acquisition images, substantially reducing the time required for these observations. All acquisitions will be on Side 2 (N2) with LSA peakup and then SAMs to the astrometrically identified knot. begincenter Method of Analysis endcenter We will obtain the density, pressure, and neon abundance for the knot and forthe integrated spectrum of the nebula (taken to matchbthe conditions of the earlier, pr-COSTAR, observations). The G140L knot spectrum will be centered on the [Ne V] and [Ne IV] lines near 1600 Angstrom to determine the neon abundance, a critical number for studying the explosion. The density at the end of 1994 was still above the critical density for the key nebular transitions. It is likely that this situation will remain true for the filaments for quite some time. Given this uncertainty, we must perform a complete photoionization analysis (CLOUDY supplemented by line profile modeling) in order to be certain of the accuracy of the derived physical conditions for the knots. We have developed a new procedure for determining the physical parameters for the knots using CLOUDY coupled with a global Metropolis Monte Carlo algorithm (Austin et al. 1994, BAAS) and will use this to determine the parameters for the individual knots. We will continue IUE observations of Nova Cyg 1992 during the entire period leading up to and including the proposed GHRS observations. We will compare these new spectra with the ones we have from 1992 and 1993. Since we have excellent velocity resolution in the earlier data, although not the spatial resolution, we will be able to identify the knots in the integrated ejecta profiles and study their development. We knew that the knots were there by comparing the 1993 April. GHRS observations with those taken in 1992 September. The filamentary emission component decreased less rapidly than the wings of the profiles on all of the emission lines. The diffuse high velocity matter was clearly distinguished from the slower moving interior knots. The contrast growth in the profiles in the second spectrum was due to a decrease in the emission measure of high velocity gas that was masking the inner, slower moving shell. We have already crudely modeled this aspect of the outburst (Shore et al. 1993) (see Starrfield and Shore (1994) for a comparison of Ne IV 1602 at the two phases). The data will be obtained, extracted, and reduced by Shore, Ake, and Starrfield. Shore and Ake are members of the GHRS Science Team and are thoroughly familiar with the instrument and the data reduction. Shore, Sonneborn, Starrfield, and Gonzalez-Riestra will be observing with IUE. Shore, Starrfield, Hauschildt, and Austin have experience modeling the emission spectrum of novae and are also involved with hydrodynamic models of the ejecta evolution. Hauschildt, Starrfield, and Shore performed the atmosphere analysis of the white dwarf atmosphere. The HST data will be reduced using the GHRS Science Team software and many special purpose routines, written by our group, for the analysis of nova spectra. Optical observations will be processed at GSFC and ASU. Additional analysis will be performed at IUSB, especially the merger of the UV and groundbased data. Real_Time_Justification: Calibration_Justification: ! Move appropriate text from Real_Time_Justification Additional_Comments: The LSA G160M observation makes use the the available time following target acquisition with side 2. The N2 mirror is required for adequate S/N; there is enough time remaining (RPS2 processing) to allow for a medium resolution He II 1640 observation for comparison with 1992 and 1993 spectra at the central star. Side switch will be performed during occultation. The knot spectrum should be taken contemporaneously with the central star on a single visit. We will continue monitoring the integrated 1200 - 2000Angstrom\ flux of Cyg 1992 with IUE through the period of these observations. Groundbased spectra will be obtained from the MMT to support the observations by Starrfield and his students. The spectra should be obtained as soon as possible after the start of Cycle 5 in order to insure that the knots are brighter than .8e-15 erg/s/cm^2/A. IUE will not be available after 31 Sept. 1995, so the observations should be scheduled as closely as possible to that time. Fixed_Targets ! Section 5.1 Target_Number: 1 Target_Name: NOVA-CYG-1992-CENTRAL-STAR Alternate_Names: V1974 CYGNI Description: STAR, CLASSICAL NOVA, PLANETARY NEBULA CENTRAL STAR Position: RA=20H 29M 07.0S +/- 0.05S, ! Most common specification format is DEC=52D 27' 44" +/- 0.05" ! RA=0H 0M 0.00S +/- 0S, ! DEC=0D 0' 0.0" +/- 0", ! PLATE-ID=0000 Equinox: 1950.0 RV_or_Z: RA_PM: ! Units are seconds of time per year Dec_PM: ! Units are seconds of arc per year Epoch: Annual_Parallax: Flux: F-LINE(1602)=1.0E-14 ! Include at least V and B-V Comments: FLUX BASED ON IUE SPECTRA NOV 1994 Target_Number: 2 Target_Name: NOVA-CYG-1992-KNOT-2 Alternate_Names: V1974 CYGNI KNOT Description: STAR, CLASSICAL NOVA, KNOT, EJECTA Position: RA-OFF = -0.0093S +/- 0.0001S, ! Most common specification format is DEC-OFF = -0.280" +/- 0.01", ! RA=0H 0M 0.00S +/- 0S, FROM 1, ! DEC=0D 0' 0.0" +/- 0", ! PLATE-ID=0000 Equinox: 1950.0 RV_or_Z: RA_PM: ! Units are seconds of time per year Dec_PM: ! Units are seconds of arc per year Epoch: Annual_Parallax: Flux: F-LINE(1602)=1.0E-14 ! Include at least V and B-V Comments: FLUX BASED ON IUE SPECTRA NOV 1994 ! This is a template for a single visit containing a single exposure ! Repeat exposure and visit blocks as needed Visits ! Section 6 Visit_Number:1 Visit_Requirements: BEFORE 30-SEP-1995 On_Hold_Comments: Visit_Comments: Exposure_Number: 1 ! Section 6.5 Target_Name: NOVA-CYG-1992-CENTRAL-STAR Config: HRS Opmode: ACQ Aperture: 2.0 Sp_Element: MIRROR-N2 Wavelength: Optional_Parameters: Number_of_Iterations: 1 Time_Per_Exposure: 36S Special_Requirements: ONBOARD ACQ FOR 2-5; NO SPLIT Comments: STEP-TIME=4S TO YIELD 500 COUNTS Exposure_Number: 2 ! Section 6.5 Target_Name: NOVA-CYG-1992-CENTRAL-STAR Config: HRS Opmode: ACCUM Aperture: 2.0 Sp_Element: G160M Wavelength: 1640 Optional_Parameters: FP-SPLIT=TWO Number_of_Iterations: 4 Time_Per_Exposure: 326.4S Special_Requirements: ! Section 7.2 Exposure_Number: 3 ! Section 6.5 Target_Name: NOVA-CYG-1992-CENTRAL-STAR Config: HRS Opmode: ACCUM Aperture: 2.0 Sp_Element: G140L Wavelength: 1340 Optional_Parameters: FP-SPLIT=TWO Number_of_Iterations: 12 Time_Per_Exposure: 326.4S Special_Requirements: ! Section 7.2 Exposure_Number: 4 ! Section 6.5 Target_Name: NOVA-CYG-1992-CENTRAL-STAR Config: HRS Opmode: ACCUM Aperture: 2.0 Sp_Element: G140L Wavelength: 1618 Optional_Parameters: FP-SPLIT=TWO Number_of_Iterations: 12 Time_Per_Exposure: 326.4S Special_Requirements: ! Section 7.2 Exposure_Number: 5 ! Section 6.5 Target_Name: NOVA-CYG-1992-KNOT-2 Config: HRS Opmode: ACCUM Aperture: 0.25 Sp_Element: G140L Wavelength: 1618 Optional_Parameters: FP-SPLIT=TWO Number_of_Iterations: 27 Time_Per_Exposure: 326.4S Special_Requirements: ! Section 7.2 Comments: 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: Steve Shore c/o Tom Ake Code 681/CSC Goddard Space Flight Center Greenbelt, MD 20771 ! STSCI or PI_Address or ! PI Address from Phase I is: ! ! Northside Hall, ! 1700 Mishawaka Ave., ! South Bend, IN 46634-7111 ! ! Ship_Via: UPS ! 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