! Hubble Space Telescope Cycle 6 (1996) Phase II Proposal Template ! $Id: 6748,v 6.1 1996/08/08 16:58:27 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: Karla Peterson ! Phone: 410-338-4774 , E-mail: peterson@stsci.edu ! ! This partially completed template was generated from a Phase I proposal. Proposal_Information ! Section 4 Title: ABUNDANCES OF VERY HEAVY ELEMENTS IN THE EARLY GALAXY. III. Proposal_Category: GO Scientific_Category: COOL STARS Cycle: 6 Investigators PI_name: JOHN COWAN PI_Institution: UNIVERSITY OF OKLAHOMA CoI_Name: CHRIS SNEDEN CoI_Institution: UNIVERSITY OF TEXAS Contact: ! Y or N (designate at most one contact) CoI_Name: JAMES TRURAN CoI_Institution: UNIVERSITY OF CHICAGO Contact: ! Y or N (designate at most one contact) Abstract: ! Free format text (please update) We propose to search for spectral lines indicating the presence of the very heavy elements platinum, iridium, lead and osmium in a very old, metal-poor halo star, and to determine the relative abundances of these elements. These elements, synthesized in stellar interiors by r(apid) and s(low) neutron capture processes, had, until our very recent successful detections in Cycle 5, never before been observed in metal-poor stars because their only strong lines lie in the ultraviolet spectral region. The abundances of these r- and s- process nucleosynthesis products in halo stars, and in particular relative and absolute star-to-star comparisons, will serve to provide important constraints on models of both the early history and chemical evolution of the Galaxy and, indirectly, on the age of the Galaxy and the universe. Questions ! Free format text (please update) Observing_Description: We will measure the abundances of the heavy r-process elements Os, Ir, Pt and the s-process element Pb in extreme Population II stars in an attempt to understand more about the early history of the Galaxy. Specifically, we will obtain spectra for all four of these elements, which have spectral lines in the ultraviolet, with wavelengths near 3000 Angstrom. We have chosen two very metal-poor halo giants for observations with the HST: HD 126238 (observed in Cycle 5) and HD 115444 (proposed here). We will use the SSA, grating 270M, and 4 substeps per diode to achieve an ultimate resolution of 50,000 while capturing about 45 Angstrom \ of spectrum per integration. The resolution requirement is due to the crowded spectral region near 3000 Angstrom \ in these stars, and the spectral coverage requirement, aside from increasing the number of candidate lines available per integration, will aid considerably in the setting of continua for our spectrum syntheses. The 270M grating is a better choice than ECH-B for it does not have the pronounced dropoff in throughput over short wavelength intervals that the short- order echelle grating does, and the larger spectral coverage allows at least two very heavy element transitions to be observed with each integration. For HD 115444, a comparison of its UBV colors and effective temperature with those of HD 126238 indicates that its 3000 Angstrom \ flux is only about 25\% that of HD 126238. To achieve a (S/N) = 50 would then require 4 hours per exposure, based upon the results of our detections in Cycle 5. We wish to observe the same three spectral regions to allow a direct comparison with our results from Cycle 5, yielding a total integration time for this new fainter star of 12 hours. Assuming three visits, adding in the target acquisition times, and overhead for each of these exposures, a sum of 18 orbits is requested for this star. Real_Time_Justification: In a related effort, Sneden and Gustafsson have recently obtained optical spectra of our target star, HD 115444. One of the goals of this supporting ground-based effort is an attempt to determine the thorium abundance in this metal- poor, but heavy element rich, halo star. Calibration_Justification: ! Move appropriate text from Real_Time_Justification Additional_Comments: Fixed_Targets ! Section 5.1 Target_Number: 1 Target_Name: HD115444 Alternate_Names: 2541-528,BD+372388,HIC64786,SAO63442 Description:STAR,GIANT O,K III-I, Position: RA=13H 16M 42.44S +/- 0.02S, ! Most common specification format is DEC=36D 22' 53.1" +/- 0.3", ! RA=0H 0M 0.00S +/- 0S, PLATE-ID=01PR ! DEC=0D 0' 0.0" +/- 0", ! PLATE-ID=0000 Equinox:J2000 RV_or_Z: V=-27.6 RA_PM: 0.012 ! Units are seconds of time per year Dec_PM: -0.071 ! Units are seconds of arc per year Epoch: 1983.133 Annual_Parallax: 0.0 Flux: V=8.98 B-V=0.78 U-B=0.18 ! Include at least V and B-V F-CONT(2650.0) = 7.0 E-14 F-CONT(3000.0) = 2.0 E-13 Comments: Cooridinates are from GSC for 2541-528. Flux at 2650A and 3000A are lower limits to Star's Flux, from the IUE spectrum of Gustaffson et al. of the Metal-poor Giant HD 122563, adjusted for the Magnitude differences between HD 122563 And our target star HD 115444. ! This is a template for a single visit containing a single exposure ! Repeat exposure and visit blocks as needed Visits ! Section 6 Visit_Number: 01 Visit_Requirements: ! Section 7.1 On_Hold_Comments: Visit_Comments: Exposure_Number:10 ! Section 6.5 Target_Name:HD115444 Config:HRS Opmode:ACQ Aperture:2.0 Sp_Element:MIRROR-N2 Wavelength: Optional_Parameters:BRIGHT=RETURN Number_of_Iterations:1 Time_Per_Exposure: 4.5S Special_Requirements: ONBOARD ACQ FOR 20 ! Section 7.2 Exposure_number: 20 Target_Name: HD115444 Config: HRS Opmode: ACQ/PEAKUP Aperture: 0.25 Sp_Element: MIRROR-N2 Wavelength: Optional_Parameters: SEARCH-SIZE=5 Number_of_iterations:1 Time_Per_Exposure: 25S Special_Requirements:ONBOARD ACQ FOR 30-40 Comments: STEP-TIME=1.0S Exposure_number: 30 Target_Name: HD115444 Config: HRS Opmode: ACCUM Aperture: 0.25 Sp_Element: G270M Wavelength: 3060.0 Optional_Parameters: COMB=FOUR, STEP-TIME=0.2, FP-SPLIT=STD, STEP-PATT=3 Number_of_iterations:6 Time_Per_Exposure: 1280.0S Special_Requirements: Comments: TOTAL EXPOSURE=7680S--BREAK UP TO AVOID DRIFT DUE TO GIMP; S/N IS PER SUBSTEP; WANT HIGH S/N IN EACH SUBSTEP FOR DECONVOLUTION. Exposure_number: 40 Target_Name: HD115444 Config: HRS Opmode: ACCUM Aperture: 0.25 Sp_Element: G270M Wavelength: 3060.0 Optional_Parameters: COMB=FOUR, STEP-TIME=0.2, FP-SPLIT=STD, STEP-PATT=3 Number_of_iterations:6 Time_Per_Exposure: 1292.8S Special_Requirements: Comments: TOTAL EXPOSURE=7757S--BREAK UP TO AVOID DRIFT DUE TO GIMP; S/N IS PER SUBSTEP; WANT HIGH S/N IN EACH SUBSTEP FOR DECONVOLUTION. Visit_Number: 02 Visit_Requirements: ! Section 7.1 On_Hold_Comments: Visit_Comments: Exposure_Number:10 ! Section 6.5 Target_Name:HD115444 Config:HRS Opmode:ACQ Aperture:2.0 Sp_Element:MIRROR-N2 Wavelength: Optional_Parameters:BRIGHT=RETURN Number_of_Iterations:1 Time_Per_Exposure: 4.5S Special_Requirements: ONBOARD ACQ FOR 20 ! Section 7.2 Exposure_number: 20 Target_Name: HD115444 Config: HRS Opmode: ACQ/PEAKUP Aperture: 0.25 Sp_Element: MIRROR-N2 Wavelength: Optional_Parameters: SEARCH-SIZE=5 Number_of_iterations:1 Time_Per_Exposure: 25S Special_Requirements:ONBOARD ACQ FOR 30-40 Comments: STEP-TIME=1.0S Exposure_number: 30 Target_Name: HD115444 Config: HRS Opmode: ACCUM Aperture: 0.25 Sp_Element: G270M Wavelength: 3060.0 Optional_Parameters: COMB=FOUR, STEP-TIME=0.2, FP-SPLIT=STD, STEP-PATT=3 Number_of_iterations:6 Time_Per_Exposure: 1280.0S Special_Requirements: Comments: TOTAL EXPOSURE=7680S--BREAK UP TO AVOID DRIFT DUE TO GIMP; S/N IS PER SUBSTEP; WANT HIGH S/N IN EACH SUBSTEP FOR DECONVOLUTION. Exposure_number: 40 Target_Name: HD115444 Config: HRS Opmode: ACCUM Aperture: 0.25 Sp_Element: G270M Wavelength: 3060.0 Optional_Parameters: COMB=FOUR, STEP-TIME=0.2, FP-SPLIT=STD, STEP-PATT=3 Number_of_iterations:6 Time_Per_Exposure: 1292.8S Special_Requirements: Comments: TOTAL EXPOSURE=7757S--BREAK UP TO AVOID DRIFT DUE TO GIMP; S/N IS PER SUBSTEP; WANT HIGH S/N IN EACH SUBSTEP FOR DECONVOLUTION. Visit_Number: 03 Visit_Requirements: ! Section 7.1 On_Hold_Comments: Visit_Comments: Exposure_Number:10 ! Section 6.5 Target_Name:HD115444 Config:HRS Opmode:ACQ Aperture:2.0 Sp_Element:MIRROR-N2 Wavelength: Optional_Parameters:BRIGHT=RETURN Number_of_Iterations:1 Time_Per_Exposure: 4.5S Special_Requirements: ONBOARD ACQ FOR 20 ! Section 7.2 Exposure_number: 20 Target_Name: HD115444 Config: HRS Opmode: ACQ/PEAKUP Aperture: 0.25 Sp_Element: MIRROR-N2 Wavelength: Optional_Parameters: SEARCH-SIZE=5 Number_of_iterations:1 Time_Per_Exposure: 25S Special_Requirements:ONBOARD ACQ FOR 30-40 Comments: STEP-TIME=1.0S Exposure_number: 30 Target_Name: HD115444 Config: HRS Opmode: ACCUM Aperture: 0.25 Sp_Element: G270M Wavelength: 3060.0 Optional_Parameters: COMB=FOUR, STEP-TIME=0.2, FP-SPLIT=STD, STEP-PATT=3 Number_of_iterations:6 Time_Per_Exposure: 1280.0S Special_Requirements: Comments: TOTAL EXPOSURE=7680S--BREAK UP TO AVOID DRIFT DUE TO GIMP; S/N IS PER SUBSTEP; WANT HIGH S/N IN EACH SUBSTEP FOR DECONVOLUTION. Exposure_number: 40 Target_Name: HD115444 Config: HRS Opmode: ACCUM Aperture: 0.25 Sp_Element: G270M Wavelength: 3060.0 Optional_Parameters: COMB=FOUR, STEP-TIME=0.2, FP-SPLIT=STD, STEP-PATT=3 Number_of_iterations:6 Time_Per_Exposure: 1292.8S Special_Requirements: Comments: TOTAL EXPOSURE=7757S--BREAK UP TO AVOID DRIFT DUE TO GIMP; S/N IS PER SUBSTEP; WANT HIGH S/N IN EACH SUBSTEP FOR DECONVOLUTION. Visit_Number: 51 Visit_Requirements: ! Section 7.1 On_Hold_Comments: Visit_Comments: Exposure_Number:10 ! Section 6.5 Target_Name:HD115444 Config:HRS Opmode:ACQ Aperture:2.0 Sp_Element:MIRROR-N2 Wavelength: Optional_Parameters:BRIGHT=RETURN Number_of_Iterations:1 Time_Per_Exposure: 4.5S Special_Requirements: ONBOARD ACQ FOR 20 ! Section 7.2 Exposure_number: 20 Target_Name: HD115444 Config: HRS Opmode: ACQ/PEAKUP Aperture: 0.25 Sp_Element: MIRROR-N2 Wavelength: Optional_Parameters: SEARCH-SIZE=5 Number_of_iterations:1 Time_Per_Exposure: 25S Special_Requirements:ONBOARD ACQ FOR 30-40 Comments: STEP-TIME=1.0S Exposure_number: 30 Target_Name: HD115444 Config: HRS Opmode: ACCUM Aperture: 0.25 Sp_Element: G270M Wavelength: 2915.0 Optional_Parameters: COMB=FOUR, STEP-TIME=0.2, FP-SPLIT=STD, STEP-PATT=3 Number_of_iterations:6 Time_Per_Exposure: 1280.0S Special_Requirements: Comments: TOTAL EXPOSURE=7680S--BREAK UP TO AVOID DRIFT DUE TO GIMP; S/N IS PER SUBSTEP; WANT HIGH S/N IN EACH SUBSTEP FOR DECONVOLUTION. Exposure_number: 40 Target_Name: HD115444 Config: HRS Opmode: ACCUM Aperture: 0.25 Sp_Element: G270M Wavelength: 2915.0 Optional_Parameters: COMB=FOUR, STEP-TIME=0.2, FP-SPLIT=STD, STEP-PATT=3 Number_of_iterations:6 Time_Per_Exposure: 1292.8S Special_Requirements: Comments: TOTAL EXPOSURE=7757S--BREAK UP TO AVOID DRIFT DUE TO GIMP; S/N IS PER SUBSTEP; WANT HIGH S/N IN EACH SUBSTEP FOR DECONVOLUTION. Visit_Number: 53 Visit_Requirements: ! Section 7.1 On_Hold_Comments: Visit_Comments: Exposure_Number:10 ! Section 6.5 Target_Name:HD115444 Config:HRS Opmode:ACQ Aperture:2.0 Sp_Element:MIRROR-N2 Wavelength: Optional_Parameters:BRIGHT=RETURN Number_of_Iterations:1 Time_Per_Exposure: 4.5S Special_Requirements: ONBOARD ACQ FOR 20 ! Section 7.2 Exposure_number: 20 Target_Name: HD115444 Config: HRS Opmode: ACQ/PEAKUP Aperture: 0.25 Sp_Element: MIRROR-N2 Wavelength: Optional_Parameters: SEARCH-SIZE=5 Number_of_iterations:1 Time_Per_Exposure: 25S Special_Requirements:ONBOARD ACQ FOR 30-40 Comments: STEP-TIME=1.0S Exposure_number: 30 Target_Name: HD115444 Config: HRS Opmode: ACCUM Aperture: 0.25 Sp_Element: G270M Wavelength: 2833.0 Optional_Parameters: COMB=FOUR, STEP-TIME=0.2, FP-SPLIT=STD, STEP-PATT=3 Number_of_iterations:6 Time_Per_Exposure: 1280.0S Special_Requirements: Comments: TOTAL EXPOSURE=7680S--BREAK UP TO AVOID DRIFT DUE TO GIMP; S/N IS PER SUBSTEP; WANT HIGH S/N IN EACH SUBSTEP FOR DECONVOLUTION. Exposure_number: 40 Target_Name: HD115444 Config: HRS Opmode: ACCUM Aperture: 0.25 Sp_Element: G270M Wavelength: 2833.0 Optional_Parameters: COMB=FOUR, STEP-TIME=0.2, FP-SPLIT=STD, STEP-PATT=3 Number_of_iterations:6 Time_Per_Exposure: 1292.8S Special_Requirements: Comments: TOTAL EXPOSURE=7757S--BREAK UP TO AVOID DRIFT DUE TO GIMP; S/N IS PER SUBSTEP; WANT HIGH S/N IN EACH SUBSTEP FOR DECONVOLUTION. Data_Distribution Medium: 8MM Blocking_Factor: 10 Ship_To: PI_Address Ship_Via: UPS Recipient_Email: