! Proposal 6656, submission 1
! PI: Dr. Judith Provencal
! Received Wed Feb 7 15:15:59 EST 1996
! From: jlp@UDel.Edu
! Hubble Space Telescope Cycle 6 (1996) Phase II Proposal Template
! $Id: 6656,v 5.1 1996/07/16 17:57:46 pepsa Exp $
! Hubble Space Telescope Cycle 6 (1996) Phase II Proposal Template
! $Id: 6656,v 5.1 1996/07/16 17:57:46 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: Manning
! Phone: 410-338-4456 , E-mail: manning@stsci.edu
!
! This partially completed template was generated from a Phase I proposal.
! Name of Phase I Proposal: archive-0694.provencal.prop
! Date generated: Fri Dec 22 16:54:35 EST 1995
!
Proposal_Information ! Section 4
Title: Hydrogen, Interstellar Accretion, and Hot
Helium Rich White Dwarfs
Proposal_Category: GO
Scientific_Category: HOT STARS
Cycle: 6
Investigators
PI_name: Dr. Judith Provencal
PI_Institution: University of Delaware
CoI_Name: Prof. Harry Shipman
CoI_Institution: University of Delaware
Contact: ! Y or N (designate at most one contact)
Abstract: ! Free format text (please update)
The study of white dwarf structure provides valuable insights
into the final stages of stellar evolution. Recently, rapid
developments in UV spectroscopy have altered our understanding
of these simplest of stars. It is now clear that hydrogen
(DA) and helium (DB) white dwarfs follow different
evolutionary paths. While it appears that once a DA is
formed, it remains a DA throughout its evolution, our
understanding of DB evolution is particularly sketchy. About
20\% of all DBs contain traces of hydrogen, and we observe a
gap in DB distribution between 30,000\ rmK< rmT_eff<45,000\
rmK. Current theory predicts that, at these temperatures,
hydrogen floats to the surface, masking the DB white dwarf
beneath a thin hydrogen photosphere. In 1992, HST obtained
high resolution spectra, centered on 1215\ Angstrom, of the
prototype DBV PG1645+325 (GD358), detecting broad shallow
absorption wings of hydrogen surrounding the geocoronal
emission. Initial results indicate that PG1645+325, rmT_eff=\
27,000 K, does not have enough hydrogen to have been a DA in
the DB gap. We propose a search for hydrogen in hot DB white
dwarfs, to test theories of DB evolution and address the
question of the uniqueness of PG1645+325.
Questions ! Free format text (please update)
Observing_Description:
The observations will be done with GHRS in ACCUM mode,
centered on 1215\ Angstrom, using the small science aperture
to reduce geocoronal emission. We have calculated
the exposure times of the other targets using previous
observations of PG1645+325 as a flux model. The exposure
times are calculated to give a signal to noise ratio of ~20
(see table). We have submitted a second proposal addressing
carbon pollution and convective dredgeup in the hotter DBs,
also motivated by earlier HST observations of PG1645+325.
Both these proposals deal with the atmospheric structure of
DB white dwarfs, yet we felt we were exploring a different
aspect of the problem with each proposal. We opted for
individual proposals because we felt we could learn something
interesting from each separately.
Real_Time_Justification:
Calibration_Justification: ! Move appropriate text from Real_Time_Justification
Additional_Comments:
Fixed_Targets ! Section 5.1
Target_Number: 1
Target_Name: GD190
Alternate_Names: PG1542+182
Description: STAR,DB
Position: RA=15H 44M 19.45S +/- 0.030S,DEC=+18D 06' 46.38" +/- 0.40",
PLATE-ID=00GM
Equinox: J2000
RV_or_Z:
RA_PM: 0.001 ! Units are seconds of time per year
Dec_PM: -0.113 ! Units are seconds of arc per year
Epoch: 1982.384033203
Annual_Parallax:
Flux: V=14.72, B-V=-0.10 ! Include at least V and B-V
Comments:
Target_Number: 2
Target_Name: PG0112+104
Alternate_Names: WD0112+104
Description: STAR, DB
Position: RA=01H 14M 37.68S +/- 0.030S,DEC=+10D 41' 05.45" +/- 0.40",
PLATE-ID=00GR
Equinox: J2000
RV_or_Z:
RA_PM: ! Units are seconds of time per year
Dec_PM: ! Units are seconds of arc per year
Epoch: 1982.7950439453
Annual_Parallax:
Flux: V=15.33,B-V=-0.03 ! Include at least V and B-V
Comments:
Solar_System_Targets ! Section 5.2
Target_Number:
Target_Name:
Description:
Level_1: ! Satellite of Sun
Level_2: ! Satellite of Level_1
Level_3: ! Satellite of Level_2
Ephem_Uncert: ! Needed for REQ EPHEM CORR sp req
Acq_Uncert: ! Needed for SAVE and USE OFFSET sp reqs
Window:
Flux: ! Include at least V and B-V
Comments:
Generic_Targets ! Section 5.3
Target_Number:
Target_Name:
Description:
Criteria:
Flux:
Comments:
Scan_Data ! Appendix B
Scan_Number:
FGS_Scan:
Cont_or_Dwell:
Dwell_Points:
Dwell_Secs:
Scan_Width:
Scan_Length:
Sides_Angle:
Number_Lines:
Scan_Rate:
First_Line_PA:
Scan_Frame:
Length_Offset:
Width_Offset:
! 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: ! Section 7.1
! Uncomment or copy visit level special requirements needed
! Most of these requirements (including ORIENT) will limit scheduling
! PCS MODE [Fine | Gyro]
! GUIDing TOLerance <angle>
! DROP TO GYRO IF NECESSARY [NO REACQuisition]
! ORIENTation <angle1> TO <angle2>
! ORIENTation <angle1> TO <angle2> FROM <visit>
! ORIENTation <angle1> TO <angle2> FROM NOMINAL
! SAME ORIENTation AS <visit>
! CVZ
! PARallel
! SCHEDulability <percentage>
! AFTER <visit> [BY <time1> [TO <time2>]]
! AFTER <date>
! BEFORE <date>
! BETWEEN <date1> AND <date2>
! GROUP <visit-list> WITHIN <time>
! PERIOD <time> AND ZERO-PHASE <date>
! SEQ <visit-list> WITHIN <time>
! ON HOLD [FOR <visit-list>]
On_Hold_Comments:
Visit_Comments:
Exposure_Number: 1 ! Section 6.5
Target_Name: GD190
Config: HRS
Opmode: ACQ
Aperture: 2.0
Sp_Element: MIRROR-N2
Wavelength:
Optional_Parameters: SEARCH-SIZE=3
Number_of_Iterations: 1
Time_Per_Exposure: 18.0S
Special_Requirements: ONBOARD ACQ FOR 2 ! Section 7.2
! Uncomment or copy exposure level special requirements needed
! INTeractive ACQuisition FOR <exp-list>
ONBOARD ACQuisition FOR 2
! SAVE OFFSET <id>
! USE OFFSET <id>
! POSition TARGet <x-value>,<y-value>
! SAME POSition AS <exp>
! DO FOR TARGets <targ-list> ! FGS only
! PARallel WITH <exp>
! GROUP-FGS <exp-list> WITHIN <time>
! SPATIAL SCAN <#> [<exp-list> | SINGLE-EXP ]
! RT ANALYSIS [FOR <exp-list>]
! REQuires UPLINK
! REQuires EPHEMeris CORRection <id>
! END ORBIT
! EXPAND
! LOW-SKY
! MAXimum DURation [<time> | <%>]
! MINimum DURation [<time> | <%>]
! NO SPLIT
! PHASE <number1[0,1]> TO <number2[0,1]>
! SEQuence <exp-list> NON-INTerruptible
! SHADOW
Exposure_Number: 2 ! Section 6.5
Target_Name: GD190
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: 50.0S
Special_Requirements: ONBOARD ACQ FOR 3-4 ! Section 7.2
! Uncomment or copy exposure level special requirements needed
! INTeractive ACQuisition FOR <exp-list>
ONBOARD ACQuisition FOR 3-4
! SAVE OFFSET <id>
! USE OFFSET <id>
! POSition TARGet <x-value>,<y-value>
! SAME POSition AS <exp>
! DO FOR TARGets <targ-list> ! FGS only
! PARallel WITH <exp>
! GROUP-FGS <exp-list> WITHIN <time>
! SPATIAL SCAN <#> [<exp-list> | SINGLE-EXP ]
! RT ANALYSIS [FOR <exp-list>]
! REQuires UPLINK
! REQuires EPHEMeris CORRection <id>
! END ORBIT
! EXPAND
! LOW-SKY
! MAXimum DURation [<time> | <%>]
! MINimum DURation [<time> | <%>]
! NO SPLIT
! PHASE <number1[0,1]> TO <number2[0,1]>
! SEQuence <exp-list> NON-INTerruptible
! SHADOW
Exposure_Number: 3 ! Section 6.5
Target_Name: WAVE
Config: HRS
Opmode: ACCUM
Aperture: SC2
Sp_Element: G160M
Wavelength: 1215
Optional_Parameters: SPYBAL=YES
Number_of_Iterations: 1
Time_Per_Exposure: DEF
Special_Requirements: ! Section 7.2
Comments:
Exposure_Number: 4 ! Section 6.5
Target_Name: GD190
Config: HRS
Opmode: ACCUM
Aperture: 0.25
Sp_Element: G160M
Wavelength: 1215
Optional_Parameters: FP-SPLIT=STD, STEP-PATT=DEF
Number_of_Iterations: 2
Time_Per_Exposure: 1740.8S
Special_Requirements: ! Section 7.2
Visit_Number: 2
Visit_Requirements: ! Section 7.1
Exposure_Number: 1 ! Section 6.5
Target_Name: PG0112+104
Config: HRS
Opmode: ACQ
Aperture: 2.0
Sp_Element: MIRROR-N2
Wavelength:
Optional_Parameters: SEARCH-SIZE=3
Number_of_Iterations: 1
Time_Per_Exposure: 54.0S
Special_Requirements: ONBOARD ACQ FOR 2 ! Section 7.2
! Uncomment or copy exposure level special requirements needed
! INTeractive ACQuisition FOR <exp-list>
ONBOARD ACQuisition FOR 2
! SAVE OFFSET <id>
! USE OFFSET <id>
! POSition TARGet <x-value>,<y-value>
! SAME POSition AS <exp>
! DO FOR TARGets <targ-list> ! FGS only
! PARallel WITH <exp>
! GROUP-FGS <exp-list> WITHIN <time>
! SPATIAL SCAN <#> [<exp-list> | SINGLE-EXP ]
! RT ANALYSIS [FOR <exp-list>]
! REQuires UPLINK
! REQuires EPHEMeris CORRection <id>
! END ORBIT
! EXPAND
! LOW-SKY
! MAXimum DURation [<time> | <%>]
! MINimum DURation [<time> | <%>]
! NO SPLIT
! PHASE <number1[0,1]> TO <number2[0,1]>
! SEQuence <exp-list> NON-INTerruptible
! SHADOW
Comments: STEP-TIME=6.0 sec
Exposure_Number: 2 ! Section 6.5
Target_Name: PG0112+104
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: 150.0S
Special_Requirements: ONBOARD ACQ FOR 3-4 ! Section 7.2
! Uncomment or copy exposure level special requirements needed
! INTeractive ACQuisition FOR <exp-list>
ONBOARD ACQuisition FOR 3-4
! SAVE OFFSET <id>
! USE OFFSET <id>
! POSition TARGet <x-value>,<y-value>
! SAME POSition AS <exp>
! DO FOR TARGets <targ-list> ! FGS only
! PARallel WITH <exp>
! GROUP-FGS <exp-list> WITHIN <time>
! SPATIAL SCAN <#> [<exp-list> | SINGLE-EXP ]
! RT ANALYSIS [FOR <exp-list>]
! REQuires UPLINK
! REQuires EPHEMeris CORRection <id>
! END ORBIT
! EXPAND
! LOW-SKY
! MAXimum DURation [<time> | <%>]
! MINimum DURation [<time> | <%>]
! NO SPLIT
! PHASE <number1[0,1]> TO <number2[0,1]>
! SEQuence <exp-list> NON-INTerruptible
! SHADOW
Comments:
Exposure_Number: 3 ! Section 6.5
Target_Name: WAVE
Config: HRS
Opmode: ACCUM
Aperture: SC2
Sp_Element: G160M
Wavelength: 1215
Optional_Parameters: SPYBAL=YES
Number_of_Iterations: 1
Time_Per_Exposure: DEF
Special_Requirements: ! Section 7.2
Comments:
Exposure_Number: 4 ! Section 6.5
Target_Name: PG0112+104
Config: HRS
Opmode: ACCUM
Aperture: 0.25
Sp_Element: G160M
Wavelength: 1215
Optional_Parameters: FP-SPLIT=STD, STEP-PATT=DEF
Number_of_Iterations: 2
Time_Per_Exposure: 2828.8S
Special_Requirements: ! 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:
!
! Department of Pysics
! Sharp Laboratory
! Newark
! 19716
!
!
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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! Please send a list of your likes and dislikes to your Program Coordinator