! File: 3336C.PROP ! Database: PEPDB ! Date: 19-FEB-1994:03:52:11 coverpage: title_1: CENTRAL STARS OF PLANETARY NEBULAE - CYCLE 3 sci_cat: STELLAR ASTROPHYSICS sci_subcat: SUBLUMINOUS STARS proposal_for: AUG/FOC cont_id: 3747 pi_title: IR. 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: 5.30 num_pri: 5 foc: Y pi_position: PROGRAM COORDINATOR ! 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: POTTASCH fname: S. title: PROF. mi: R inst: GRONINGEN, UNIVERSITY OF country: NETHERLANDS esa: Y ! lname: ZIJLSTRA fname: A. title: DR. mi: A inst: GRONINGEN, UNIVERSITY OF country: NETHERLANDS esa: Y ! lname: WALTON fname: N. title: DR. inst: UNIVERSITY COLLEGE LONDON country: ENGLAND esa: Y ! lname: KAMPERMAN fname: T. mi: M inst: SRON SPACE RESEARCH UTRECHT country: NETHERLANDS esa: Y ! ! 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 sharp central peak line_2: in HST's PSF will result in a much higher detectability of central stars. line_3: Where the detectability ratio HST/ground was originally at least 400, line_4: the ratio is still about 70 in the same observation time. ! question: 5 section: 1 line_1: No special scheduling requests. ! question: 6 section: 1 line_1: All proposers have access to state-of-the-art data analysis line_2: facilities at their home institutions. ! question: 7 section: 1 line_1: All objects have been GASP-ed at the STSCI. ! question: 8 section: 1 line_1: In CYCLE 1 NGC7027 was observed in a very small field. line_2: Maybe due to a mispointing the star observed was not the wanted line_3: central star. This is still under imvestigation. ! question: 9 section: 1 line_1: All three institutes have sufficient resources to support this project ! !end of general form text general_form_address: lname: KAMPERMAN fname: T. mi: M title: IR. category: PI inst: SRON SPACE RESEARCH UTRECHT addr_1: SORBONNELAAN 2 addr_2: 3584 CA city: UTRECHT country: NETHERLANDS phone: 3130535715 telex: NL 47224 ! ! end of general_form_address records fixed_targets: targnum: 1 name_1: NGC6741 descr_1: A,184 pos_1: RA=19H02M37S+/-.5S, pos_2: DEC=-00D26'58"+/-2", equinox: J2000 rv_or_z: V=40 acqpr_1: EXT plate_avail: Y fluxnum_1: 1 fluxval_1: V=10.2+/-.2 fluxnum_2: 2 fluxval_2: SURF(V)=13.8+/-1. fluxnum_3: 3 fluxval_3: F(4861)=4.1+/-0.5E-12 fluxnum_4: 4 fluxval_4: SURF(1500)=4.5+/-1.E-17 ! targnum: 2 name_1: NGC2440 descr_1: A,184 pos_1: RA=07H41M55.4S+/-.5S, pos_2: DEC=-18D12'33.0"+/-2", equinox: J2000 rv_or_z: V=45 acqpr_1: EXT fluxnum_1: 1 fluxval_1: V=9.0+/-.2 fluxnum_2: 2 fluxval_2: SURF(V)=16.9+/-3. fluxnum_3: 3 fluxval_3: F(4861)=2.9+/-2.E-11 ! targnum: 3 name_1: NGC6886 descr_1: A,184 pos_1: RA=20H12M43S+/-.5S, pos_2: DEC=19D58'37"+/-2", equinox: J2000 rv_or_z: V=35 acqpr_1: EXT plate_avail: Y fluxnum_1: 1 fluxval_1: V=10.2+/-.2 fluxnum_2: 2 fluxval_2: SURF(V)=13.8+/-1. fluxnum_3: 3 fluxval_3: F(4861)=4.9+/-0.5E-12 fluxnum_4: 4 fluxval_4: SURF(1500)=5.4+/-1.E-17 ! targnum: 4 name_1: NGC6537 descr_1: A,184 pos_1: RA=18H05M13.3S+/-.5S, pos_2: DEC=-19D50'14.0"+/-2", equinox: J2000 rv_or_z: V=-4 acqpr_1: EXT fluxnum_1: 1 fluxval_1: V=9.6+/-.2 fluxnum_2: 2 fluxval_2: SURF(V)=15.8+/-1. fluxnum_3: 3 fluxval_3: F(4861)=9.5+/-1.E-12 ! targnum: 5 name_1: NGC6445 descr_1: A,184 pos_1: RA=17H49M15.2S+/-.5S, pos_2: DEC=-20D00'34.0"+/-2", equinox: J2000 rv_or_z: V=29 acqpr_1: EXT fluxnum_1: 1 fluxval_1: V=9.5+/-.2 fluxnum_2: 2 fluxval_2: SURF(V)=19.6+/-1. fluxnum_3: 3 fluxval_3: F(4861)=1.6+/-1.E-11 ! ! end of fixed targets ! No solar system records found ! No generic target records found exposure_logsheet: linenum: 1.000 sequence_1: DEFINE sequence_2: SIZE512 targname: # config: FOC/96 opmode: IMAGE aperture: 512X512 sp_element: F130M num_exp: 1 time_per_exp: 8M fluxnum_1: 3 priority: # ! linenum: 2.000 sequence_1: DEFINE sequence_2: SIZE512 targname: # config: FOC/96 opmode: IMAGE aperture: 512X512 sp_element: F210M num_exp: 1 time_per_exp: 8M fluxnum_1: 3 priority: # ! linenum: 3.000 sequence_1: DEFINE sequence_2: SIZE512 targname: # config: FOC/96 opmode: IMAGE aperture: 512X512 sp_element: F278M num_exp: 1 time_per_exp: 8M fluxnum_1: 3 priority: # ! linenum: 4.000 sequence_1: USE sequence_2: SIZE512 targname: NGC6741 priority: 1 req_1: CYCLE 3 ! linenum: 5.000 sequence_1: USE sequence_2: SIZE512 targname: NGC2440 priority: 1 req_1: CYCLE 3 ! linenum: 6.000 sequence_1: USE sequence_2: SIZE512 targname: NGC6886 priority: 1 req_1: CYCLE 3 ! linenum: 7.000 sequence_1: USE sequence_2: SIZE512 targname: NGC6537 priority: 1 req_1: CYCLE 3 ! linenum: 8.000 sequence_1: USE sequence_2: SIZE512 targname: NGC6445 priority: 1 req_1: CYCLE 3 ! ! end of exposure logsheet ! No scan data records found