! File: 2570C.PROP ! Database: PEPDB ! Date: 17-FEB-1994:08:23:46 coverpage: title_1: RECENT MASS EJECTION FROM PLANETARY-NEBULA NUCLEI sci_cat: STELLAR ASTROPHYSICS sci_subcat: LATE EVOLUTION proposal_for: GO pi_title: DR. pi_fname: HOWARD pi_mi: E. pi_lname: BOND pi_inst: STSCI pi_country: USA pi_phone: 301-338-4718 keywords_1: WHITE DWARF, PLANETARY NEBULAE, CENTRAL STARS, STELLAR keywords_2: EVOLUTION, MASS LOSS hours_pri: 3.15 num_pri: 2 foc: X fos: X funds_amount: 99999 funds_length: 12 funds_date: OCT-91 pi_position: ASTRONOMER off_fname: H. off_mi: S. off_lname: STOCKMAN off_title: DEPUTY DIRECTOR off_inst: SPACE TELESCOPE SCIENCE INSTITUTE off_addr_1: 3700 SAN MARTIN DRIVE off_city: BALTIMORE off_state: MD. off_zip: 21218 off_country: USA off_phone: 301-338-4730 ! end of coverpage abstract: line_1: We propose HST FOC imagery of two unusual central stars of planetary line_2: nebulae. V605 Aq1, the central star of Abell 58, appeared as a 10th-mag red line_3: giant for several years around 1920, but is now fainter than 20th mag and line_4: appears to lie inside a compact knot of very hydrogen-deficient nebulosity. line_5: HST UV images can directly establish that the central star is now extremely line_6: hot, providing the first direct evidence for thermal pulses that are line_7: predicted to occur in hot pre-white-dwarfs. line_9: 0950+139, the central star of EGB 6, is presently a hot white dwarf, line_10: surrounded by a compact, unresolved nebula. FOC imagery in the [O III] and line_11: H-beta emission lines will establish one of the following. (1) The compact line_12: nebula remains unresolved from HST, implying ongoing mass loss from the white line_13: dwarf, for which there is no physical understanding at present. (2) The nebula line_14: shows sub-arcsecond structure (a hollow shell, blobs, or jets). implying a line_15: discrete mass-ejection event, most probably associated with a "self-induced line_16: nova" outburst in the fairly recent past. The latter would again provide line_17: evidence for an event theoretically predicted to occur in some hot white line_18: dwarfs. (3) The nebula shows disk-like structure, suggesting that it arises line_19: from ablation of a planetary companion. ! ! end of abstract general_form_proposers: lname: RENZINI fname: ALVIO inst: BOLOGNA, UNIVERSITY OF country: ITALY esa: X ! lname: LIEBERT fname: JAMES mi: W. inst: ARIZONA, UNIVERSITY OF country: USA ! lname: BOND fname: HOWARD title: P.I. mi: E. inst: STSCI country: USA ! ! end of general_form_proposers block general_form_text: question: 2 section: 1 line_1: (See original proposal for Scientific Justification) ! question: 3 section: 1 line_1: V605 AQL: For this object, we will search for a very hot star line_2: that may lie at the center of the planetary nebula Abell 58. line_3: We will use the FOC to obtain high-resolution images of the line_4: central [O III] knot, using two ultraviolet filters (F165W and line_5: F220W) and an optical filter (F437M) that excludes nebular line_6: emission lines. If a hot point source is found, follow-up line_7: spectroscopic observations will be obtained with the FOS. line_8: In addition, we will obtain images in the [O III] line, line_9: using F501N, in order to study the morphology of the central knot. line_11: 0950+139: We will again use the FOC, with [O III] (F501N) and line_12: H-beta (F486N) filters, in order to study the detailed morphology line_13: of the compact nebula surrounding the central star. We are line_14: attempting to distinguish between a white dwarf with ongoing mass line_15: loss (for which a scale of 10 AU or an unresolved 0.020" is line_16: expected) and a discrete ejection event in the recent past or line_17: ablation from a planetary companion (for which a resolvable scale line_18: of order 100 AU = 0.2" is possible). ! question: 4 section: 1 line_1: (See original proposal) ! question: 5 section: 1 line_1: (See original proposal) ! question: 6 section: 1 line_1: The FOS observations of V605 Aql must be scheduled AFTER the line_2: FOC observations, since final details of the spectroscopic line_3: observations depend on what is seen with the FOC. line_5: NOTE: We are assuming that STScI will calibrate the PSF for line_6: the FOC filters that we are using, to sufficient accuracy to line_7: study the sub-arcsecond surroundings of our two targets. ! question: 7 section: 1 line_1: (See original proposal) ! question: 8 section: 1 line_1: The initial FOC UV imagery of V605 Aql should be regarded both as line_2: science images, and as "early acquisitions" from which the precise line_3: position and brightness of the central point source (if any) line_4: will be determined. ! question: 9 section: 1 line_1: N/A ! question: 10 section: 1 line_1: (See original proposal) ! !end of general form text general_form_address: lname: BOND fname: HOWARD mi: E. title: DR. category: PI inst: SPACE TELESCOPE SCIENCE INSTITUTE addr_1: 3700 SAN MARTIN DR. city: BALTIMORE state: MD zip: 21218 country: USA ! ! end of general_form_address records fixed_targets: targnum: 1 name_1: V605AQL-KNOT name_2: ABELL58-CENTRAL-KNOT descr_1: STAR; CENTRAL STAR; WHITE DWARF; descr_2: DEGENERATE STAR; PLANETARY NEBULA; KNOT; descr_3: CIRCUMSTELLAR pos_1: PLATE-ID=02CT, pos_2: RA=19H 18M 20.51S +/- 1", pos_3: DEC=+01D 46' 59.4" +/- 1" equinox: J2000 fluxnum_1: 1 fluxval_1: V=21 ! targnum: 2 name_1: V605AQL-STAR name_2: ABELL58-CENTRAL-STAR descr_1: STAR; CENTRAL STAR; WHITE DWARF; descr_2: DEGENERATE STAR; PLANETARY NEBULA; descr_3: CIRCUMSTELLAR; VARIABLE pos_1: TBD-EARLY, pos_2: RA=19H 18M 20.51S +/- 2", pos_3: DEC=+01D 46' 59.4" +/- 2" equinox: J2000 acqpr_1: BKG fluxnum_1: 1 fluxval_1: V=21 ! targnum: 3 name_1: 0950+139 name_2: EGB6-CENTRAL-STAR descr_1: STAR; TYPE=DA; CENTRAL STAR; WHITE DWARF; descr_2: DEGENERATE STAR; PLANETARY NEBULA; descr_3: CIRCUMSTELLAR pos_1: PLATE-ID=01X2, pos_2: RA=09H 52M 58.98S +/- 0.7", pos_3: DEC=+13D 44' 33.7" +/- 0.7" equinox: J2000 fluxnum_1: 1 fluxval_1: V=16.0 fluxnum_2: 2 fluxval_2: B-V=-0.30 ! ! end of fixed targets ! No solar system records found ! No generic target records found exposure_logsheet: linenum: 1.000 targname: V605AQL-KNOT config: FOC/96 opmode: IMAGE aperture: 512X512 sp_element: F165W num_exp: 1 time_per_exp: 800S fluxnum_1: 1 priority: 1 req_1: SAME ORIENT FOR 2-4 AS 1; req_2: CYCLE 1 / 1-11 ! linenum: 2.000 targname: V605AQL-KNOT config: FOC/96 opmode: IMAGE aperture: 512X512 sp_element: F220W num_exp: 1 time_per_exp: 800S fluxnum_1: 1 priority: 1 ! linenum: 3.000 targname: V605AQL-KNOT config: FOC/96 opmode: IMAGE aperture: 512X512 sp_element: F437M num_exp: 1 time_per_exp: 800S fluxnum_1: 1 priority: 1 ! linenum: 4.000 targname: V605AQL-KNOT config: FOC/96 opmode: IMAGE aperture: 512X512 sp_element: F501N num_exp: 1 time_per_exp: 800S fluxnum_1: 1 priority: 1 ! linenum: 5.000 targname: V605AQL-STAR config: FOS/BL opmode: ACQ/BINARY aperture: 4.3 sp_element: MIRROR num_exp: 1 time_per_exp: 120S fluxnum_1: 1 priority: 1 req_1: ONBOARD ACQ FOR 6; req_2: REQ DATA FROM 1-4 / 5-9 comment_1: FOR LINES 5-9, PRECISE TARGET comment_2: LOCATION, EXPOSURE TIMES, AND CHOICE comment_3: OF SCIENCE APERTURE WILL BE DETERMINED comment_4: ON BASIS OF THE FOC OBSERVATIONS comment_5: IN LINES 1-4. ENTRIES ON LINES 5-9 ARE comment_6: PROVISIONAL. ! linenum: 6.000 targname: V605AQL-STAR config: FOS/BL opmode: ACCUM aperture: 0.5 sp_element: G160L wavelength: 1150-2200 num_exp: 1 time_per_exp: 2500S s_to_n: 10 fluxnum_1: 1 priority: 1 ! linenum: 7.000 targname: V605AQL-STAR config: FOS/RD opmode: ACQ/BINARY aperture: 4.3 sp_element: MIRROR num_exp: 1 time_per_exp: 90S fluxnum_1: 1 priority: 1 req_1: ONBOARD ACQ FOR 8-9; ! linenum: 8.000 targname: V605AQL-STAR config: FOS/RD opmode: ACCUM aperture: 0.5 sp_element: PRISM wavelength: 1850-8950 num_exp: 1 time_per_exp: 2500S s_to_n: 10 fluxnum_1: 1 priority: 1 ! linenum: 9.000 targname: V605AQL-STAR config: FOS/RD opmode: ACCUM aperture: 0.5 sp_element: G650L wavelength: 3750-7500 num_exp: 1 time_per_exp: 2500S s_to_n: 10 fluxnum_1: 1 priority: 1 ! linenum: 10.000 targname: 0950+139 config: FOC/96 opmode: IMAGE aperture: 512X512 sp_element: F486N num_exp: 1 time_per_exp: 800S fluxnum_1: 1 priority: 1 req_1: SAME ORIENT FOR 11 AS 10 ! linenum: 11.000 targname: 0950+139 config: FOC/96 opmode: IMAGE aperture: 512X512 sp_element: F501N num_exp: 1 time_per_exp: 800S fluxnum_1: 1 priority: 1 ! ! end of exposure logsheet ! No scan data records found