! Proposal 5884, submission 2
! Visit 1 revised 6/5/95
! PI: Wayne Landsman
! Received Mon Mar 27 17:10:37 EST 1995
! From: landsman@idlastro.gsfc.nasa.gov
! Proposal 5884, submission 1
! PI: Wayne Landsman
! Received Mon Mar 20 10:30:24 EST 1995
! From: landsman@idlastro.gsfc.nasa.gov
! Hubble Space Telescope Cycle 5 (1995) Phase II Proposal Template
! $Id: 5884,v 10.1 1995/06/09 18:56:39 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: Alice Berman
! Phone: 410 338-4462 , E-mail: aberman@stsci.edu
!
! This partially completed template was generated from a Phase I proposal.
Proposal_Information ! Section 4
Title: A White Dwarf Probe of Interstellar
Deuterium
Proposal_Category: GO
Scientific_Category: Interstellar Medium
Cycle: 5
Investigators
PI_name: Wayne Landsman
PI_Institution: Hughes STX
CoI_Name: Pierre Bergeron
CoI_Institution: Universite de Montreal
Contact: ! Y or N (designate at most one contact)
CoI_Name: Ulysses Sofia
CoI_Institution: NRC/NASA/GSFC
Contact: ! Y or N (designate at most one contact)
Abstract: ! Free format text (please update)
We propose to obtain GHRS echelle observations of interstellar
hydrogen and deuterium toward the hot (Teff ~ 50,000 K) white
dwarf HZ 43. EUV observations of HZ 43 (d = 65 pc) show it
to be located in an unusually low column density direction
(N(HI) ~ 6.5 * 10^17 cm^-2). Previous GHRS observations toward
late-type stars have demonstrated the capability to study
interstellar deuterium Ly-alpha\ in directions where the total
column density is less than ~ 3 * 10^18 cm^-2. However, the
derived D/H abundances toward late-type stars includes a
systematic uncertainty due to the complex and poorly
understood line profile of the chromospheric Ly-alpha\
emission. In contrast, the spectrum of HZ 43 has been
successfully fit with a pure hydrogen model atmosphere at all
wavelengths at which it has been observed. A second
advantage of HZ 43 over late-type stars as a probe of the D/H
abundance is its strong EUV and FUV continuum. In particular,
the 504-912 Angstrom\ EUV continuum provides an independent
check on the HI column density derived from Ly-alpha, and we
will use the FUV continuum to observe interstellar species of
small Doppler width, such as Mg II and Fe II, to resolve the
velocity structure along the line of sight. Our simulations
show that HZ 43 is sufficiently bright to yield a good S/N
echelle spectrum at Ly-alpha, and likely provide the most
unbiased estimate of D/H in the local interstellar medium.
Questions ! Free format text (please update)
Observing_Description:
Six of our nine orbits will be dedicated to observing the Ly-
alpha\ profile of HZ 43 with the echelle. We will use the
large aperture to maximize the S/N. Geocoronal emission
will be present but this emission is sufficiently narrow (<
0.1 Angstrom) that it can be placed entirely within the
saturated interstellar core by observing at times of the year
when the Earth's velocity toward HZ 43 matches the bulk
velocity of the ISM toward HZ43 (~ -12 kms). To characterize
the velocity and component structure we will use Ech-B to
observe the Mg II Lambda2800 doublet and Fe II Lambda2382.
The lines have been selected on the basis of their moderate
strength (\log NfLambda (cm^-1) ~ 6.8-7.9) for the expected
column density toward HZ 43. There are other moderate
strength lines such as Si II Lambda1260, OI Lambda1302, Fe
Lambda1608 that would be useful for studying depletions, but
we defer their observations for future observing cycles. We
will also obtain a medium resolution G160 spectrum at 1210
Angstrom\ to cover the entire broad (~ 30 Angstrom) white
dwarf Ly-alpha\ absorption, in order to confirm the accuracy
of the adopted model profile. begincenter
begintabularrrrrrrrr Line & Wave & Orbit & Grating & Aper &
Exp Time & S/N , NI, Ly-alpha & 1210 & 1 & G160M
& SSA & 23m & 25 , Ly-alpha & 1215.7 & 2-7 & Ech-
A & LSA & 275m & 22 , Mg II & 2795, 2803 & 8 & Ech-B &
LSA & 40m & 25 , Fe II & 2382 & 9 & Ech-B &
LSA & 43m & 25 , endtabular endcenter
Real_Time_Justification:
We request observations during certain times
of the year (within a 4 month period) when the Earth velocity
matches the bulk interstellar velocity toward HZ 43.
Calibration_Justification: None. ! Move appropriate text from Real_Time_Justification
Additional_Comments:
Fixed_Targets ! Section 5.1
! Updated target coordinates 5/16/95 - AFB
Target_Number: 1
Target_Name: HZ43
Alternate_Names: GSC1996-01402,WD1314+293
Description: STAR, DA
Position: RA = 13H 16M 21.99S +/- 0.02S,
DEC = 29D 05' 57.0" +/- 0.2",
PLATE-ID = 002K
Equinox: J2000
RV_or_Z:
RA_PM: -0.0116 +/- 0.0002 ! Units are seconds of time per year
Dec_PM: -0.0813 +/- 0.0095 ! Units are seconds of arc per year
Epoch: 1982.387
Annual_Parallax: 0.0155 +/- 0.0034
Flux: V = 12.89,
B-V = -0.10,
F(1215) = 5 +/- 1 E-13,
F(2382) = 4 +/- 0.5 E-13,
F(2800) = 2.7 +/- 0.5 E-13
Comments: Coordinates are from GSC
! Original values:
! Position:
! RA = 13H 16M 21.994S +/- 0.01S,
! DEC = 29D 05' 57.02" +/- 0.2",
! PLATE-ID=002K
! Epoch: J1982.39
! 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: BETWEEN 30-JUL-1995 AND 5-OCT-1995
Visit_Comments: ALSO BETWEEN 18-MAR-1996 AND 23-MAY-1996
Exposure_Number: 11 ! Section 6.5
Target_Name: HZ43
Config: HRS
Opmode: ACQ
Aperture: 2.0
Sp_Element: MIRROR-N1
Wavelength:
Optional_Parameters: BRIGHT=RETURN
Number_of_Iterations: 1
Time_Per_Exposure: 9S
Special_Requirements: ONBOARD ACQ FOR 12-14 ! Section 7.2
Comments: STEP-TIME=1S; EXPECT 3700 COUNTS IN STEP-TIME
Exposure_Number: 12 ! Section 6.5
Target_Name: HZ43
Config: HRS
Opmode: ACCUM
Aperture: 2.0
Sp_Element: ECH-A
Wavelength: 1215.6
Optional_Parameters: FP-SPLIT=STD
Number_of_Iterations: 12
Time_Per_Exposure: 652.8s
Special_Requirements:
Exposure_Number: 13 ! Section 6.5
Target_Name: WAVE
Config: HRS
Opmode: ACCUM
Aperture: SC2
Sp_Element: ECH-A
Wavelength: 1215.6
Optional_Parameters: SPYBAL=YES
Number_of_Iterations: 1
Time_Per_Exposure: DEF
Special_Requirements:
Comments: WAVECAL for exposure 14,
Do NOT move carrousel
Exposure_Number: 14 ! Section 6.5
Target_Name: HZ43
Config: HRS
Opmode: ACCUM
Aperture: 2.0
Sp_Element: ECH-A
Wavelength: 1215.6
Optional_Parameters: FP-SPLIT=STD, SPYBAL=NO
Number_of_Iterations: 11
Time_Per_Exposure: 652.8s
Special_Requirements:
! --- END VISIT 1 --- END VISIT 1 --- END VISIT 1 --- END VISIT 1 ---
Visit_Number: 2
Visit_Requirements: ! Section 7.1
BETWEEN 30-JUL-1995 AND 5-OCT-1995
Visit_Comments: ALSO BETWEEN 18-MAR-1996 AND 23-MAY-1996
Exposure_Number: 21 ! Section 6.5
Target_Name: HZ43
Config: HRS
Opmode: ACQ
Aperture: 2.0
Sp_Element: MIRROR-N2
Wavelength:
Optional_Parameters: BRIGHT=RETURN
Number_of_Iterations: 1
Time_Per_Exposure: 1.8S ! Changed from orig. 9 seconds 6/9/95
Special_Requirements: ONBOARD ACQ FOR 22-23 ! Section 7.2
Comments: STEP-TIME=0.2S; EXPECT 11860 COUNTS IN STEP-TIME
Exposure_Number: 22 ! Section 6.5
Target_Name: HZ43
Config: HRS
Opmode: ACCUM
Aperture: 2.0
Sp_Element: ECH-B
Wavelength: 2382
Optional_Parameters: FP-SPLIT=STD
Number_of_Iterations: 4
Time_Per_Exposure: 544s
Special_Requirements: ! Section 7.2
Comments: Fe II ! Section 7.2
Exposure_Number: 23 ! Section 6.5
Target_Name: HZ43
Config: HRS
Opmode: ACCUM
Aperture: 2.0
Sp_Element: ECH-B
Wavelength: 2800
Optional_Parameters: FP-SPLIT=STD
Number_of_Iterations: 4
Time_Per_Exposure: 544s
Special_Requirements: ! Section 7.2
Comments: Mg II ! Section 7.2
Exposure_Number: 24 ! Section 6.5
Target_Name: HZ43
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: 5S ! Changed from orig. 25 sec per PI 6/9/95
Special_Requirements: ONBOARD ACQ FOR 25
Comments: STEP-TIME=0.2, EXPECT 5900 COUNTS IN STEP-TIME ! Per PI 6/9/95
Exposure_Number: 25 ! Section 6.5
Target_Name: HZ43
Config: HRS
Opmode: ACCUM
Aperture: 0.25
Sp_Element: G160M
Wavelength: 1210
Optional_Parameters:
Number_of_Iterations: 13
Time_Per_Exposure: 108.8s
Special_Requirements:
Comments: Ly Alpha ! Section 7.2
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: PI_Address ! STSCI or PI_Address or <free-text>
! PI Address from Phase I is:
!
! Code 681 , NASA/GSFC, Greenbelt
! , MD 20771
!
!
Ship_Via: UPS ! UPS (2-day) or OVERNIGHT
! Overnight shipping done at PI expense
Recipient_Email: ! Needed if Ship_To: is not PI_Address
! <free-text>
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