! $Id: 5610,v 5.1 1994/07/27 19:45:04 pepsa Exp $ coverpage: title_1: SYMBIOTIC SYSTEMS IN THE MAGELLANIC CLOUDS title_2: CYCLE 4 HIGH sci_cat: HOT STARS sci_subcat: ERUPTIVE BINARIES proposal_for: GO/DD pi_fname: MANFRED pi_lname: VOGEL pi_inst: ETH ZURICH pi_country: SWITZERLAND hours_pri: 4.20 num_pri: 2 fos: Y off_fname: JAN off_lname: STENFLO off_title: HEAD OF INSTITUTE off_inst: 7820 off_addr_1: ETH ZENTRUM off_city: 8092 ZURICH off_country: SWITZERLAND off_phone: 41-1-632 3804 ! end of coverpage abstract: line_1: We propose FOS observations of line_2: symbiotic systems in the Magellanic Clouds. The goal of this line_3: proposal is twofold : (1) The main goal is an accurate line_4: determination of the luminosity and radiation temperature of the line_5: hot component in symbiotic systems. That knowledge is of prime line_6: importance when trying to situate symbiotics in an evolutionary line_7: scenario. Since distances to galactic symbiotics are very badly line_8: known, observations in the Magellanic Clouds can be the basis for line_9: a breakthrough. (2) From the nebular spectrum we can fairly easily line_10: determine relative CNO abundances of symbiotic nebulae. As the line_11: nebula has its origin in the red giant, this provides a line_12: straightforward method for determining relative C/N/O abundances line_13: of the Magellanic red giants without the uncertainties of a line_14: stellar atmosphere analysis. Up to now almost all information line_15: about the chemistry of the Clouds has been derived from H II line_16: regions and planetary nebulae. The proposed observations present line_17: therefore also a new possibility for studying abundances in the line_18: Magellanic Clouds. ! ! end of abstract general_form_proposers: lname: VOGEL fname: MANFRED title: PI inst: ETH ZURICH country: SWITZERLAND esa: Y ! lname: NUSSBAUMER fname: HARRY inst: ETH ZURICH country: SWITZERLAND esa: Y ! lname: SHORE fname: STEVEN mi: N. inst: COMPUTER SCIENCES CORPORATION country: USA ! ! end of general_form_proposers block general_form_text: question: 3 section: 1 line_1: For determining the radiation temperature and luminosity of the line_2: hot component we need to observe the He II 1640 line and the line_3: continuum to wavelengths as short as possible. As these observations line_4: do not require high resolution, we plan for each target one exposure line_5: with the G130H grating, observed in the 4.3 arcsec aperture. line_6: As a side benefit we obtain at the shortest HST wavelengths some of line_7: the most interesting nebular emission lines like N V 1240, line_8: the dielectronic recombination line O V 1371 and the multiplet line_9: Si IV 1401. They give additional information on the ionization state line_10: of these objects. line_11: For abundance determinations we need absolute fluxes of the line_12: CNO lines in the UV: C III] 1908, C IV 1550, N III] 1750, N IV] line_13: 1486, and O III] 1664. In addition to the G130H observation for the line_14: temperature and luminosity determination, one complementary exposure line_15: with the G190H grating will provide the C III] 1908 line. Thus, two line_16: exposures for every target would then cover the range from line_17: 1150 to 2300 A, and contain all the crucial emission lines line_18: as well as a sufficiently broad fraction of the stellar and line_19: nebular continuum to determine the shape of the continuous energy line_20: distribution. ! question: 4 section: 1 line_1: By their very nature symbiotics demand observations in the far UV. The line_2: hot components have radiation temperatures of at least 50000 K, but line_3: mostly of 100000 K and higher. Contrary to other classes of double line_4: star systems, the hot components are only directly observable at the line_5: shortest wavelengths accessible with HST. On the other hand, the line_6: luminous M giant which dominates the visual and the infrared, makes line_7: essentially no contribution in the far UV. line_8: IUE provided a tremendous boost to research of galactic symbiotics. line_9: However, the limited sensitivity and the low dynamic range of IUE line_10: prevented anything beyond an exploratory study of symbiotic systems in line_11: the Magellanic Clouds in the UV. The FOS on HST is very well suited line_12: for an extension of research to extragalactic symbiotics. There is at line_13: present no substitute for the dynamic range required by our proposal line_14: and provided by HST. In addition, since the hot components in line_15: symbiotic systems are only directly observable at wavelengths shorter line_16: than 1600 A, the FOS is the most suited instrument for the line_17: proposed scientific goal, and there is obviously no ground-based line_18: substitute. ! question: 5 section: 1 line_1: S 63-LMC is reasonably well observed with IUE to estimate line_2: absolute fluxes in the UV. We use this star as a reference and line_3: scale the exposure times for the targets with unknown UV fluxes line_4: according to their blue or visual magnitudes. The visual line_5: magnitude of S 63 is V = 15.6, and the ultraviolet flux is line_6: approximately 1E-14 erg/cm/cm/sec/Ang at 1500 A. The strength of line_7: the three emission lines C III] 1908, N III] 1750, and O III] line_8: 1664 which are in the G190H range is between 3E-14 and 4E-14 line_9: erg/cm/cm/sec, and the line width we estimate to be approximately 2 A. ! question: 5 section: 2 line_1: The exposure times for S 63 are calculated as follows : the line_2: calibration curve of the FOS/BL (Gilliland and Hartig 1991) yield line_3: for G130H at 1500 A about 1E+13 cts/diode/sec per line_4: erg/cm/cm/sec/A, and the sensitivity of G190H is about 2E+13 line_5: cts/diode/sec per erg/cm/cm/sec/A at 1640 A, and higher for line_6: longer wavelengths. For a S/N = 10 in the continuum this requires line_7: an integration time of 1000 sec using the G130H grating in order line_8: to obtain the energy distribution of the hot object. For the He line_9: II 1640 equivalent width and the emission lines of C III] 1908, N III] line_10: 1750, and O III] 1664 an integration time of 300 sec will line_11: provide a S/N of about 10 in the emission lines and in the He II line_12: 1640 equivalent width. All exposures will be taken through the line_13: 4.3 arcsec aperture. The total exposure time for S 63 line_14: would therefore be approx. 22 min. The exposure times for Ln 358 line_15: are calculated assuming that it has about the same spectral distribution line_16: as S 63, and that the exposure times will simply scale with the line_17: V magnitude. The indivudual exposure times are chosen to tune the line_18: the total spacecraft to the allocated 4.2 hours. The total number of line_19: targets is 2, the total number of visits is also 2, and the total number line_20: of exposures is 4. ! question: 6 section: 1 line_1: None ! ! question: 8 section: 1 line_1: None. ! question: 9 section: 1 line_1: Nr. 2342 - The symbiotic phenomenon. line_2: (Michalitsianos, Fahey, Kafatos, Nussbaumer, Paresce) line_3: The observations have not yet been done. The goal of that project, line_4: which will concentrate on the symbiotic star R Aqr (which is not a line_5: symbiotic nova), is not related to the purpose of this proposal. ! question: 10 section: 1 line_1: At ETH (Swiss Federal Institute of Technology) we have excellent line_2: computer facilities which we can access directly from our line_3: institute, e.g. Cray YMP, VAX 9000. Allocation of requested line_4: computer access and time has never been a problem. In addition we line_5: have several computer work stations as part of the infrastructure line_6: of our institute. From ETH and the Swiss Science Foundation we line_7: have always received grants for two to three Ph.D. students to line_8: work on these projects, in addition two post-doctoral positions line_9: have been granted to work on HST related projects. Travel money line_10: needed is included in the budget of our institute. Cray YMP time line_11: will also be available at GSFC. SPAN links between institutions line_12: will permit rapid exchange of, and analysis of, the HST data. ! !end of general form text general_form_address: lname: VOGEL fname: MANFRED category: PI inst: ETH Zurich addr_1: ETH ZENTRUM city: 8092 ZURICH country: SWITZERLAND phone: 41-1-632 3806 ! ! end of general_form_address records fixed_targets: targnum: 1 name_1: S63 descr_1: A,155 pos_1: RA = 05H 48M 43.2S +/- 0.1S, pos_2: DEC = -67D 36' 09.1" +/- 1" equinox: 2000 fluxnum_1: 1 fluxval_1: V = 14.7 ! targnum: 5 name_1: LN358 descr_1: A,155 pos_1: RA = 00H 59M 12.4S +/- 0.1S, pos_2: DEC = -75D 05' 17.2" +/- 1" equinox: 2000 fluxnum_1: 1 fluxval_1: V = 15.0 ! ! end of fixed targets ! No solar system records found ! No generic target records found exposure_logsheet: linenum: 3.000 targname: S63 config: FOS/BL opmode: ACQ/PEAK aperture: 4.3 sp_element: MIRROR num_exp: 1 time_per_exp: 10S fluxnum_1: 1 priority: 3 param_1: SEARCH-SIZE-X=1 param_2: SEARCH-SIZE-Y=3 param_3: SCAN-STEP-Y=1.204 req_1: ONBOARD ACQ FOR 4; req_2: CYCLE 4 / 3-18 comment_1: COARSE PEAK-UP IN 4.3 ! linenum: 4.000 targname: S63 config: FOS/BL opmode: ACQ/PEAK aperture: 1.0 sp_element: MIRROR num_exp: 1 time_per_exp: 10S fluxnum_1: 1 priority: 3 param_1: SEARCH-SIZE-X=6 param_2: SEARCH-SIZE-Y=2 param_3: SCAN-STEP-X=.602 param_4: SCAN-STEP-Y=.602 req_1: ONBOARD ACQ FOR 5-6 comment_1: FINE PEAK-UP IN 1.0 ! linenum: 5.000 targname: S63 config: FOS/BL opmode: ACCUM aperture: 4.3 sp_element: G130H num_exp: 1 time_per_exp: 25M s_to_n: 10 fluxnum_1: 1 priority: 3 ! linenum: 6.000 targname: S63 config: FOS/BL opmode: ACCUM aperture: 4.3 sp_element: G190H num_exp: 1 time_per_exp: 15M s_to_n: 10 fluxnum_1: 1 priority: 3 ! linenum: 15.000 targname: LN358 config: FOS/BL opmode: ACQ/PEAK aperture: 4.3 sp_element: MIRROR num_exp: 1 time_per_exp: 10S fluxnum_1: 1 priority: 1 param_1: SEARCH-SIZE-X=1 param_2: SEARCH-SIZE-Y=3 param_3: SCAN-STEP-Y=1.204 req_1: ONBOARD ACQ FOR 16 comment_1: COARSE PEAK-UP IN 4.3 ! linenum: 16.000 targname: LN358 config: FOS/BL opmode: ACQ/PEAK aperture: 1.0 sp_element: MIRROR num_exp: 1 time_per_exp: 10S fluxnum_1: 1 priority: 1 param_1: SEARCH-SIZE-X=6 param_2: SEARCH-SIZE-Y=2 param_3: SCAN-STEP-X=.602 param_4: SCAN-STEP-Y=.602 req_1: ONBOARD ACQ FOR 17-18 comment_1: FINE PEAK-UP IN 1.0 ! linenum: 17.000 targname: LN358 config: FOS/BL opmode: ACCUM aperture: 4.3 sp_element: G130H num_exp: 1 time_per_exp: 30M s_to_n: 10 fluxnum_1: 1 priority: 1 ! linenum: 18.000 targname: LN358 config: FOS/BL opmode: ACCUM aperture: 4.3 sp_element: G190H num_exp: 1 time_per_exp: 20M s_to_n: 10 fluxnum_1: 1 priority: 1 ! ! end of exposure logsheet