!  File:  1254C.PROP
!  Database:  PEPDB
!  Date:  16-FEB-1994:07:58:15

coverpage:

  title_1:         CENTRAL STARS OF PLANETARY NEBULAE
    sci_cat:       STELLAR ASTROPHYSICS
    sci_subcat:    SUBLUMINOUS STARS
    proposal_for:  GTO/FOC
    pi_fname:      T.
    pi_mi:         M.
    pi_lname:      KAMPERMAN
    pi_inst:       SRON SPACE RESEARCH UTRECHT
    pi_country:    NETHERLANDS
    pi_phone:      3130535715
    keywords_1:    PLANETARY NEBULAE, HOT CENTRAL STARS.
    hours_pri:     1.00
    num_pri:       1
! end of coverpage

abstract:

    line_1:        It has proved impossible to detect the very hot exciting stars of some
    line_2:        planetary neblae from the ground. This is probably because these stars emit a
    line_3:        great many ionizing photons for each visible quantum. The ionized nebula is
    line_4:        therefore so extensive that the nebular emission, both line and continuum,
    line_5:        completely dominate the visual continuum emission of the central star, which
    line_6:        becomes lost in the noise. Observing above the atmosphere increases the
    line_7:        possibility of detection of these central star by a factor of at least 400. A
    line_8:        factor ~ 100 because the light of the central star is within an image of. 1"
    line_9:        instead of the ~ 1" ground seeing limitation allowing better discrimination of
    line_10:       the star against the diffuse nebular continuum and a further factor ~ 4 occurs
    line_11:       because the star is that much brighter, relative to the nebula, in the
    line_12:       ultraviolet than it is in the visible.
    line_13:       With the spherical abberation of HST, the above mentioned factor of 100 is
    line_14:       reduced to about 15, but as the UV adventage remains, detectability is still
    line_15:       several magnitudes beyond groundobservations.

!
! end of abstract

general_form_proposers:

  lname:           REAY
    fname:         N.
    mi:            K.
    inst:          IMPERIAL COLLEGE, LONDON
    country:       UNITED KINGDOM
    esa:           X

!

  lname:           ATHERTON
    fname:         P.
    mi:            D.
    inst:          GRONINGEN, UNIVERSITY OF
    country:       NETHERLANDS
    esa:           X

!

  lname:           POTTASCH
    fname:         S.
    mi:            R.
    inst:          GRONINGEN, UNIVERSITY OF
    country:       NETHERLANDS
    esa:           X

!

  lname:           WALTON
    fname:         N.
    inst:          GRONINGEN, UNIVERSITY OF
    country:       NETHERLANDS
    esa:           X

!

  lname:           KAMPERMAN
    fname:         T.
    mi:            M.
    inst:          SRON SPACE RESEARCH UTRECHT
    country:       NETHERLANDS
    esa:           X

!
! end of general_form_proposers block

general_form_text:

  question:        3
    section:       1
    line_1:        For each object 3 exposure images will be taken through different narrow band
    line_2:        U.V. filters. The filters are chosen so that we avoid areas of the spectrum
    line_3:        with strong emission lines, and seperated by a reasonable wavelength interval.
    line_4:        This serves two purposes.
    line_5:        a) We will be able to discriminate between low temperature field stars and the
    line_6:        true central star by measuring their colour temperature,
    line_7:        b) If there is an enhancement in the nebular continuum surrounding the central
    line_8:        star, we will be able to seperate the contributions from the nebular and
    line_9:        stellar continuum surrounding the central star, we will be able to seperate
    line_10:       the contributions from the nebular and stellar continuum by their different
    line_11:       gradients.

!

  question:        4
    section:       1
    line_1:        The combination of ultraviolet sensitivity and the much higher spatial
    line_2:        resolution compared to ground-based work will increase the sensitivity for
    line_3:        detection of the central stars by a factor of at least 400.
    line_4:        With the abberated mirror this factor is reduced to about 70.

!

  question:        10
    section:       1
    line_1:        All three institutes have sufficient resources to support this project

!

  question:        13
    section:       1
    line_1:        UV OBSERVATION OF VERY HOT, HIGH MASS CENTRAL STARS OF PLANETARY NEBULAE

!
!end of general form text

general_form_address:

  lname:           KAMPERMAN
    fname:         T.
    mi:            M.
    category:      PI
    inst:          SRON SPACE RESEARCH UTRECHT
    addr_1:        SORBONNELAAN 2
    addr_2:        3584 CA
    city:          UTRECHT
    country:       NETHERLANDS
    telex:         NL 47224

!
! end of general_form_address records

fixed_targets:

    targnum:       1
    name_1:        NGC7027
    descr_1:       CENTRAL STAR OF PLANETARY NEBULA
    pos_1:         RA=21H07M1.7S+/-.5S,
    pos_2:         DEC=42D14'9.4"+/-2"
    equinox:       2000
    pm_or_par:     NO
    rv_or_z:       V=10
    acqpr_1:       EXT
    plate_avail:   Y
    fluxnum_1:     1
    fluxval_1:     V=8.6+/-.2
    fluxnum_2:     2
    fluxval_2:     SURF(V)=14.4+/-1.
    fluxnum_3:     3
    fluxval_3:     F(4861)=6.8+/-1.E-11
    fluxnum_4:     4
    fluxval_4:     SURF(1500)=7.6+/-2.E-16

!
! end of fixed targets

! No solar system records found

! No generic target records found

exposure_logsheet:

    linenum:       1.000
    sequence_1:    DEFINE
    sequence_2:    SIZE256
    targname:      #
    config:        FOC/96
    opmode:        IMAGE
    aperture:      256X256
    sp_element:    F130M
    num_exp:       1
    time_per_exp:  8M
    fluxnum_1:     4
    priority:      #

!

    linenum:       2.000
    sequence_1:    DEFINE
    sequence_2:    SIZE256
    targname:      #
    config:        FOC/96
    opmode:        IMAGE
    aperture:      256X256
    sp_element:    F210M
    num_exp:       1
    time_per_exp:  8M
    fluxnum_1:     4
    priority:      #

!

    linenum:       3.000
    sequence_1:    DEFINE
    sequence_2:    SIZE256
    targname:      #
    config:        FOC/96
    opmode:        IMAGE
    aperture:      256X256
    sp_element:    F278M
    num_exp:       1
    time_per_exp:  8M
    fluxnum_1:     4
    priority:      #
    comment_1:     THIS 256 MODE APPLIES FOR SMALL
    comment_2:     NEBULAE WHERE CENTRAL OBJECT WILL BE
    comment_3:     WITHIN FIELD OF VIEW. MAGNITUDE
    comment_4:     CENTRAL STARS UNKNOWN.

!

    linenum:       4.000
    sequence_1:    USE
    sequence_2:    SIZE256
    targname:      NGC7027
    priority:      1
    req_1:         CYCLE 1

!
! end of exposure logsheet

! No scan data records found