! $Id: 5405,v 12.1 1994/07/27 17:36:00 pepsa Exp $ coverpage: title_1: THE HIGH MASS WHITE DWARF IN HR 8210 CYCLE 4 MEDIUM sci_cat: HOT STARS sci_subcat: WHITE DWARFS proposal_for: GO pi_fname: WAYNE pi_mi: B pi_lname: LANDSMAN pi_inst: HUGHES STX pi_country: USA pi_phone: (301)-286-3625 hours_pri: 6.17 num_pri: 1 hrs: Y time_crit: Y ! end of coverpage abstract: line_1: We have recently identified the strong EUV source HR 8210 as a line_2: Sirius-like binary consisting of an A-type star and a massive line_3: (M=1.15 (+0.05,-0.15) Msun) white dwarf. We propose to observe line_4: the white dwarf Lyman-ALPHA profile at radial velocity conjunction line_5: and at both quadratures during the 22 day orbit to measure the line_6: gravitational redshift and the orbital velocity amplitude. These line_7: measurements will provide estimates of the white dwarf mass line_8: independent of a mass-radius relation, and thus provide a fundamental line_9: test of the Hamada-Salpeter relation at high white dwarf masses. line_10: Our observations will also yield an accurate Lyman-ALPHA profile for line_11: a gravity determination, an estimate of the interstellar HI column line_12: density, and a search for C III 1175 and Si III 1206 metal lines in line_13: the white dwarf. ! ! end of abstract general_form_proposers: lname: LANDSMAN fname: WAYNE mi: B inst: 3480 country: USA ! lname: SIMON fname: THEODORE inst: 2190 country: USA ! lname: BERGERON fname: PIERRE inst: 4648 country: CANADA ! ! end of general_form_proposers block general_form_text: question: 3 section: 1 line_1: We will obtain 60 minute Lyman-ALPHA observations of HR 8210 with the line_2: G160M grating at the both radial velocity quadratures and at the line_3: conjunction with the white dwarf in front. These three observations line_4: correspond to phases 0.0, 0.5 and 0.25 in the spectroscopic orbit given line_5: by Latham et al. (1994). During the conjunction, we will also obtain line_6: a spectrum centered at 1175 A to search for C III absorption, and to line_7: better define the blue wing of the Lyman-ALPHA profile, which was poorly line_8: observed with IUE. We will use the large aperture to maximize the line_9: signal to noise of the Lyman-ALPHA profile. Contamination from the line_10: gecoronal emission will be limited to one or two diodes in the core line_11: of the profile. We will check the wavelength calibration in two line_12: ways. First, we will obtain a wavelength calibration at Lyman-ALPHA line_13: prior to each of the three Lyman-ALPHA observations. In addition, we line_14: will obtain a 3 minute G160M observation of the stellar Al III lines line_15: near 1850 A star to verify that the GHRS wavelength scale matches the line_16: known radial velocity orbit of the Am primary. ! question: 4 section: 1 line_1: The white dwarf in HR 8210 is separated from the much brighter Am line_2: primary by only 0.005 arc sec, and thus is not detectable at line_3: wavelengths longer than 1500 A. The white dwarf was first discovered line_4: from our low-dispersion IUE observations (Landsman et al PASP, 105, line_5: 841). High-resolution and high signal to noise ultraviolet line_6: observations are required to measure the orbital and gravitational line_7: redshift velocities. These observations are not possible with line_8: high-dispersion IUE observations because the optimal exposure times line_9: are too long (43 hours), the signal to noise is limited (< 20) by line_10: fixed pattern noise, and the expected overexposure at 1900 A due to line_11: the Am primary would exceed the current safe limits for IUE. ! question: 5 section: 1 line_1: We are requesting observations during radial velocity conjunction line_2: (with the white dwarf in front) and the two quadratures during 21.7 line_3: day period orbit of HR 8210. There is no need for these three line_4: observations to be in the same orbit, and the observations can be line_5: within +-1 day of the specified phase. line_6: These timed observations are important to measure the orbital velocity line_7: amplitude of the white dwarf, and to distinguish between stellar and line_8: interstellar features. However, the observations at these phases line_9: is not absolutely essential for our primary goal of measuring the line_10: gravitational redshift. ! question: 6 section: 1 line_1: We request that an wavelength calibration be taken prior to each line_2: of the three observations of the Lyman alpha line of HR 8210. line_3: An accurate wavelength calibration is essential for our velocity line_4: measurement ! ! question: 10 section: 1 line_1: Compute facilities for the processing, analysis, and theoretical line_2: modeling of HST data ! !end of general form text general_form_address: lname: LANDSMAN fname: WAYNE mi: B category: PI inst: 3480 addr_1: HUGHES STX addr_2: CODE 681 addr_3: NASA/GSFC city: GREENBELT state: MD zip: 20771 country: USA phone: (301)-286-3625 telex: LANDSMAN@STARS.GSFC.NASA.GOV ! ! end of general_form_address records fixed_targets: targnum: 1 name_1: HD204188 name_2: HR8210 name_3: IK-PEG descr_1: A, 120, 124, 128 pos_1: RA = 21H 26M 26.67S +/- 0.01S, pos_2: DEC = 19D 22' 32.24" +/- 0.1", equinox: 2000 pm_or_par: Y pos_epoch_bj: J pos_epoch_yr: 2000.00 ra_pm_val: 0.005800 dec_pm_val: 0.0180 rv_or_z: V = -12 fluxnum_1: 1 fluxval_1: V=6.07, TYPE = A8V, B-V = 0.24 fluxnum_2: 2 fluxval_2: E(B-V) = 0.0 fluxnum_3: 3 fluxval_3: F(1855) = 5.0 +/- 0.1 E-12 fluxnum_4: 4 fluxval_4: F(1210) = 2.0 +/- 0.2 E-13 fluxnum_5: 5 fluxval_5: F(1175) = 9.0 +/- 0.1 E-13 ! ! end of fixed targets ! No solar system records found ! No generic target records found exposure_logsheet: ! linenum: 10.000 targname: HD204188 config: HRS opmode: ACQ aperture: 2.0 sp_element: MIRROR-A2 num_exp: 1 time_per_exp: 9S fluxnum_1: 1 priority: 1 param_1: BRIGHT=RETURN, param_2: PEAKUP=YES req_1: CYCLE 4; req_2: SEQ 10.0-14.0 NO GAP; req_3: PERIOD 21.714896D +/- 0.0042D; req_4: ZERO-PHASE JD2449070.08 +/- 0.003D; req_5: PHASE 0.25 +/- 0.07; req_6: ONBOARD ACQ FOR 11-14; comment_1: STEP-TIME=1.0S comment_2: EXPECT 1200 CTS IN STEP-TIME comment_3: RADIAL VELOCITY CONJUNCTION ! ! linenum: 11.000 targname: WAVE config: HRS opmode: ACCUM aperture: SC2 sp_element: G160M wavelength: 1210 num_exp: 1 time_per_exp: 60S fluxnum_1: 1 priority: 1 req_1: CYCLE 4; req_3: CALIB FOR 12.0; comment_1: STANDARD SPECTRAL CAL LAMP SPECTRUM ! linenum: 12.000 targname: HD204188 config: HRS opmode: ACCUM aperture: 2.0 sp_element: G160M wavelength: 1210 num_exp: 1 time_per_exp: 56M s_to_n: 16 s_to_n_time: 56M fluxnum_1: 4 priority: 1 param_1: FP-SPLIT=STD req_1: CYCLE 4; comment_1: BROAD LYMAN ALPHA ABSORPTION PROFILE ! linenum: 13.000 targname: HD204188 config: HRS opmode: ACCUM aperture: 2.0 sp_element: G160M wavelength: 1175 num_exp: 1 time_per_exp: 25M s_to_n: 16 s_to_n_time: 25M fluxnum_1: 5 priority: 1 param_1: FP-SPLIT=STD req_1: CYCLE 4; comment_1: CENTER ON CIII 1175 ! linenum: 14.000 targname: HD204188 config: HRS opmode: ACCUM aperture: 2.0 sp_element: G160M wavelength: 1855 num_exp: 1 time_per_exp: 3M s_to_n: 22 s_to_n_time: 3M fluxnum_1: 3 priority: 1 param_1: FP-SPLIT=STD req_1: CYCLE 4; comment_1: AL III 1855 ANGSTROMS ! linenum: 20.000 targname: HD204188 config: HRS opmode: ACQ aperture: 2.0 sp_element: MIRROR-A2 num_exp: 1 time_per_exp: 9S fluxnum_1: 1 priority: 1 param_1: BRIGHT=RETURN, param_2: PEAKUP=YES, req_1: CYCLE 4; req_2: PHASE 0.00 +/- 0.1 OF REF 10.0; req_3: ONBOARD ACQ FOR 21-23; req_4: SEQ 20.0-23.0 NO GAP; comment_1: STEP_TME=1.0S comment_2: EXPECT 1200 CTS IN STEP-TIME ! linenum: 21.000 targname: WAVE config: HRS opmode: ACCUM aperture: SC2 sp_element: G160M wavelength: 1210 num_exp: 1 time_per_exp: 60S fluxnum_1: 1 priority: 1 req_1: CYCLE 4; req_4: CALIB FOR 22.0; comment_1: STANDARD SPECTRAL CAL LAMP SPECTRUM ! linenum: 22.000 targname: HD204188 config: HRS opmode: ACCUM aperture: 2.0 sp_element: G160M wavelength: 1210 num_exp: 1 time_per_exp: 56M s_to_n: 16 s_to_n_time: 56M fluxnum_1: 4 priority: 1 param_1: FP-SPLIT=STD req_1: CYCLE 4; comment_1: BROAD LYMAN ALPHA ABSORPTION PROFILE ! linenum: 23.000 targname: HD204188 config: HRS opmode: ACCUM aperture: 2.0 sp_element: G160M wavelength: 1855 num_exp: 1 time_per_exp: 3M s_to_n: 22 s_to_n_time: 3M fluxnum_1: 3 priority: 1 param_1: FP-SPLIT=STD req_1: CYCLE 4; comment_1: AL III 1855 ANGSTROMS ! linenum: 30.000 targname: HD204188 config: HRS opmode: ACQ aperture: 2.0 sp_element: MIRROR-A2 num_exp: 1 time_per_exp: 9S fluxnum_1: 1 priority: 1 param_1: BRIGHT=RETURN, param_2: PEAKUP=YES, req_1: CYCLE 4; req_2: PHASE 0.50 +/- 0.1 OF REF 10.0; req_3: ONBOARD ACQ FOR 31-33; req_4: SEQ 30.0-33.0 NO GAP; comment_1: STEP_TME=1.0S comment_2: EXPECT 1200 CTS IN STEP-TIME ! linenum: 31.000 targname: WAVE config: HRS opmode: ACCUM aperture: SC2 sp_element: G160M wavelength: 1210 num_exp: 1 time_per_exp: 60S fluxnum_1: 1 priority: 1 req_1: CYCLE 4; req_2: CALIB FOR 32.0; comment_1: STANDARD SPECTRAL CAL LAMP SPECTRUM ! linenum: 32.000 targname: HD204188 config: HRS opmode: ACCUM aperture: 2.0 sp_element: G160M wavelength: 1210 num_exp: 1 time_per_exp: 56M s_to_n: 16 s_to_n_time: 56M fluxnum_1: 4 priority: 1 param_1: FP-SPLIT=STD req_1: CYCLE 4; comment_1: BROAD LYMAN ALPHA ABSORPTION PROFILE ! linenum: 33.000 targname: HD204188 config: HRS opmode: ACCUM aperture: 2.0 sp_element: G160M wavelength: 1855 num_exp: 1 time_per_exp: 3M s_to_n: 22 s_to_n_time: 3M fluxnum_1: 3 priority: 1 param_1: FP-SPLIT=STD req_1: CYCLE 4; comment_1: AL III 1855 ANGSTROMS ! ! end of exposure logsheet ! No scan data records found