! File: 3054C.PROP ! Database: PEPDB ! Date: 18-FEB-1994:13:05:52 coverpage: title_1: COSMIC ABUNDANCES AT Z=1.0 - SHORT PROGRAM sci_cat: QUASARS & AGN sci_subcat: QUASAR ABSORPTION proposal_for: SAT/FOS pi_fname: E. MARGARET pi_lname: BURBIDGE pi_inst: UC, SAN DIEGO pi_country: USA pi_phone: (619) 534-4477 keywords_1: UV SPECTROSCOPY, QUASAR, INTERGALACTIC ABSORPTION LINE, keywords_2: EMISSION LINE PROFILE, ABUNDANCE EVOLUTION, LYMAN ALPHA hours_pri: 1.67 num_pri: 1 fos: Y ! end of coverpage abstract: line_1: We will use the FOS to measure the strengths of absorption line_2: lines in the UV in a QSO which has known absorption in the line_3: optical. This will enable us to determine the ability of the line_4: FOS to measure and deconvolve UV absorption lines in faint line_5: objects in the light of the degraded performance due to the line_6: slit losses, decreased resolution, possible increased line_7: scattered light and greater than expected particle-induced line_8: background. These observations will enable us to determine line_9: the relative abundance of the elements in a galaxy at line_10: z=1.0. ! ! end of abstract general_form_proposers: lname: BEAVER fname: EDWARD inst: UC, SAN DIEGO country: USA ! lname: BURBIDGE fname: E. MARGARET inst: UC, SAN DIEGO country: USA ! lname: MARGON fname: BRUCE inst: WASHINGTON, UNIVERSITY OF country: USA ! lname: ANGEL fname: J. ROGER mi: P. inst: ARIZONA, UNIVERSITY OF country: USA ! lname: BARTKO fname: FRANK inst: MARTIN MARIETTA CORPORATION country: USA ! lname: DAVIDSEN fname: ARTHUR mi: F. inst: JOHNS HOPKINS UNIVERSITY country: USA ! lname: HARMS fname: RICHARD mi: J. inst: APPLIED RESEARCH CORPORATION country: USA ! lname: BOHLIN fname: RALPH inst: SPACE TELESCOPE SCIENCE INSTITUTE country: USA ! lname: FORD fname: HOLLAND mi: C. inst: SPACE TELESCOPE SCIENCE INSTITUTE country: USA ! ! end of general_form_proposers block general_form_text: question: 2 section: 1 line_1: Observations of 0302-223 will characterize the ability of the FOS to line_2: measure absorption lines in faint objects as well as making a determination line_3: of the relative abundance of the elements in an object with z=1.0, at a line_4: look-back time of roughly 50% of the age of the universe. Determining the line_5: relative abundances of the elements over time is a key to understanding line_6: galaxy formation and evolution. These kinds of observations will allow us line_7: to determine the abundance of the elements at a critical range of line_8: look-back-times, where this measurement is impossible from the ground line_9: because of the absence of key absorption features. Because high resolution line_10: observations are available from the ground, a key problem with the curve of line_11: growth technique, the uncertainty in the number and velocity dispersion of line_12: individual components of the absorption lines, can be minimized. Because line_13: the abundance analysis, as well as a number of other key FOS programs, such line_14: as the evolution of the C IV absorption and Lyman alpha forest in quasars line_15: depend on accurate measurements of equivalent widths, it is necessary to line_16: demonstrate the accuracy with which we can do this. 0302-223 is the line_17: brightest object (see below) available to us within the proposed line_18: restrictions in right ascension which will enable us to perform this test. line_19: The 6000s G270H observations will, in line_20: principal, determine equivalent widths to a 1 sigma limit of 0.071 line_21: Angstrom, assuming that the 0.5 arc second diameter FOS aperture transmits line_22: 23.5% of the incident light. However, the FOS performance is degraded from ! question: 2 section: 2 line_1: predicted in three ways. First, much less light gets through the aperture. line_2: Second, the (unresolved) absorption lines are broadened by a significant line_3: amount. Third, both of these problems are compounded by scattered light, line_4: which is probably increased over that predicted for the FOS both because line_5: much less light now goes through the entrance aperture and because much line_6: more light than predicted now grazes the edge of the aperture. This line_7: scattered light fills in the absorption lines and causes a systematic line_8: decrease in the measured equivalent widths. Finally, all measurements of line_9: faint objects are increased in difficulty because the FOS background is line_10: approximately .01 c/s/d, considerably greater than predicted based on line_11: ground based calibrations. line_12: With the G270H grating we can measure the strengths of several strong, line_13: low-ionization lines which must be present in the UV, based on what we know line_14: about the optical spectrum. Additionally, we know that the spectrum will line_15: not be cut off by any Lyman limit absorption long of the wavelengths of line_16: these lines. There may also be additional weaker features, including the C line_17: IV blend and Lyman alpha forest absorption lines. Additionally there will line_18: be a strong Lyman alpha emission line. Thus we will simultaneously test line_19: the ability of the FOS to make conduct several of its important scientific line_20: projects. line_21: With this test, we will first determine whether the FOS can detect line_22: absorption lines in a moderately faint object, although one which is ! question: 2 section: 3 line_1: considerably brighter than many that people will wish to observe. This is line_2: a qualitatively different test than measuring absorption lines in a bright line_3: star, for example. Second we can test deconvolution techniques on the type line_4: of data which people will obtain. If the object has C IV absorption (a line_5: closely spaced doublet), as it likely will have, this will provide a line_6: critical test of such techniques. Third, because of the high line_7: signal-to-noise of these observations, we can split them into pieces and line_8: compare the equivalent width measurements. This will allow us to test the line_9: accuracy of the (highly orbital position dependant) particle induced line_10: background subtraction. It may also allow us to test for other effects, line_11: such as an increase in sky background near the limb of the earth. We line_12: stress that this is the best available candidate for this test; it is line_13: bright, will have light in the UV, and will have known absorption, (A few line_14: brighter objects have the interesting absorption at wavelengths where the line_15: FOS is less efficient.) while at the same time it is similar to other line_16: objects that people will wish to observe. In addition, it is scientifically line_17: interesting. ! question: 3 section: 1 line_1: This proposal contains 1 object which will be observed with line_2: G270H the Red Detector of the FOS. S/N will be line_3: 40 per diode allowing us to measure absorption line_4: as well as as emission lines. All exposures are cycle 0. ! question: 4 section: 1 line_1: The main point of this program is to determine the effects of line_2: the actual HST and FOS performance on the abilities of the line_3: FOS to carry out some of its unique observations. ! question: 5 section: 1 line_1: The signal-to-noise calculation assumed transmission line_2: through the 0.5 arc second diameter of 23.5% and a total line_3: HST+FOS efficiency of 4.8% with G270H. line_4: The equivalent width limits will permit us to measure line_5: moderately strong lines to 10%. ! question: 6 section: 1 line_1: The OV prerequisite programs for all observations are: line_2: Prop ID 2188, 2189, 1441, 1442, and 1443 line_3: The SV prerequisite program for all observations is: line_4: Prop ID 2195 ! question: 7 section: 1 line_1: To characterize the performance of the HST + FOS, we will line_2: measure the equivalent widths of absorption lines, in the line_3: total observation as well as in shorter segments of the total line_4: integration. We will compare the flux levels in portions to line_5: check the particle-induced background subtraction. We will line_6: do spectral deconvolution and simulations to determine the line_7: effect of the decreased spectral resolution of the FOS on line_8: our observations ! question: 8 section: 1 line_1: We will schedule ground-based observations at Lick Observatory line_2: as close to the HST observations in time as possible to provide line_3: an estimate of the absolute flux to test the HST flux calibration line_4: and to provide additional scientific input. ! !end of general form text general_form_address: lname: BURBIDGE fname: E. MARGARET category: PI inst: UC, SAN DIEGO ! lname: COHEN fname: ROSS mi: D. category: CON inst: UNIVERSITY OF CALIFORNIA, SAN DIEGO addr_1: CASS DEPT., C-011 city: LA JOLLA state: CA zip: 92093 country: USA phone: (619) 534-2664 telex: FAX: (619) 534-6316 ! ! end of general_form_address records fixed_targets: targnum: 1 name_1: 1E0302-223 descr_1: QUASAR pos_1: RA = 03H 04M 49.823S +/- 1.0", pos_2: DEC = -22D 11' 51.91" +/- 1.0", pos_3: PLATE-ID = 025C equinox: 2000 pm_or_par: NO rv_or_z: Z=1.40 fluxnum_1: 1 fluxval_1: V=16.3 +/- 0.5 ! ! end of fixed targets ! No solar system records found ! No generic target records found exposure_logsheet: linenum: 1.000 targname: 1E0302-223 config: FOS/RD opmode: ACQ/BINARY aperture: 4.3 sp_element: MIRROR num_exp: 1 time_per_exp: 11S fluxnum_1: 1 priority: 1 param_1: BRIGHT = 700000 req_1: ONBOARD ACQ FOR 2-3; req_3: CYCLE 0 / 1-3 ! linenum: 2.000 targname: ^ config: ^ opmode: ACQ aperture: ^ sp_element: ^ num_exp: 1 time_per_exp: 11S fluxnum_1: 1 priority: ^ ! linenum: 3.000 targname: ^ config: ^ opmode: ACCUM aperture: 0.5 sp_element: G270H wavelength: 2700 num_exp: 1 time_per_exp: 6000S s_to_n: 40 fluxnum_1: ^ priority: ^ param_1: STEP-PATT=SINGLE ! ! end of exposure logsheet ! No scan data records found