Page 1 PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID 3946c Report Date: 09-May-96:18:58 Version: ********** Check-in Date: ********** 1.Proposal Title: HIGHLY EVOLVED STARS OF LOW MASS CYCLE 2 BASELINE: FOS SPECTRA OF NPN 7027 ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Proposal Type 5. Continuation ID STELLAR ASTROPHYSICS GTO/HRS Sub Category SUBLUMINOUS STARS ------------------------------------------------------------------------------------ 6. Principal Investigator Institution Country Telephone Sara R. Heap NASA, GODDARD SPACE FLIGHT C USA 301-344-5359 ------------------------------------------------------------------------------------ 7. Abstract The FOS will be used to obtain a spectrum of the central star of the planetary nebulae, NGC 7027. This star is one of the hottest stars known (170,000 K). ------------------------------------------------------------------------------------ 8. Scientific Key Words: PLANETARY NEBULAE, PLANETARY NUCLEI ------------------------------------------------------------------------------------ 9. Est obs time (hours) pri: 1.84 par: 0 10. Num targs pri: 9 par: 0 ------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------ Page 2 I. GENERAL FORM Proposal 3946c PI: Sara R. Heap Proposal Title: HIGHLY EVOLVED STARS OF LOW MASS CYCLE 2 BASELINE: FOS SPECTRA OF NPN 7027 ------------------------------------------------------------------------------------ 1. Proposers: Proposers Institution Country ESA ------------------------------------------------------------------------------------ Sara R. Heap NASA, GODDARD SPACE FLIGHT USA CENTER Pat Harrington UNIV. OF MARYLAND, COLLEGE PARK USA Ivan Hubeny NASA, GODDARD SPACE FLIGHT USA CENTER ------------------------------------------------------------------------------------ 3. Description of proposed observations. In our Cycle 2 baseline time, we'll obtain a FOS spectrum of the central star of NGC 7027. ------------------------------------------------------------------------------------ 4. Justification of need for HST observations. High spatial resolution is necessary to isolate the central from the bright surrounding nebula. ------------------------------------------------------------------------------------ 5. Description of special scheduling requirements. No special scheduling requirements are expected. ------------------------------------------------------------------------------------ 6. Description of special calibration exposures. The central star of NGC 7027 is very faint. Observations of this objects should be attempted only in low-dark periods (no SAA). ------------------------------------------------------------------------------------ 7. Data reduction and analysis plans. Carry out an non-LTE analysis of the central star, which is expected to be a VERY hot white dwarf. ------------------------------------------------------------------------------------ 13. We propose to study central stars of planetary nebulae, including (1) extremely hot stars, (2) the carbon-rich stars and nebulae, (3) stars with strong winds, and (4) uv-bright stars to be discovered in globular clusters. ------------------------------------------------------------------------------------ 11. Address Information Name: SARA R. HEAP Category: PI Institution: GODDARD SPACE FLIGHT CENTER Address: CODE 681 City: GREENBELT State: MD Zip Code: 20771 Country: USA Telephone: 301-344-9545 Telex (or e-mail): ------------------------------------------------------------------------------------ TARGET LIST a) Fixed Targets ID = 3946c [ 3] ------------------------------------------------------------------------------------------------------------------------------------ 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial |Acqui|FLX| Flux data No | Name | Description | Position |Eqnx | Vel. |Prblm|REF| | | | | | | | | ------------------------------------------------------------------------------------------------------------------------------------ 4 NGC7027- A RA=21H 07M 2.695S +/- 0.75", 2000 OFFSET DEC= +42D 14' 10.09" +/- 0.75" Comments: COORDINATES ARE MEASURED FROM PLATE (TAKEN AT CFHT UNDER VERY GOOD SEEING) USING THE GSSS. HST WILL EXECUTE BLIND OFFSET TO NGC7027-STAR. ------------------------------------------------------------------------------------------------------------------------------------ 6 NGC7027-STAR A, 184 RA-OFF= -0.933S +/- 0.027S, 2000 BKG 1 F(4800)=0.128E-14 DEC-OFF= -0.100" +/- 0.3", 2 V=16.14, E(B-V)=0.90 FROM 4 Comments: COORDINATES ARE MEASURED FROM PLATE (TAKEN AT CFHT UNDER 0.7" SEEING) USING THE GSSS. HST WILL EXECUTE BLIND OFFSET FROM NGC7027-OFFSET. ------------------------------------------------------------------------------------------------------------------------------------ 7 NGC7027-NEB RA-OFF= -0.933S +/- 0.027S, 2000 DEC-OFF= -2.100" +/- 0.3", FROM 4 Comments: NEBULAR BKG 2" S OF CSPN ------------------------------------------------------------------------------------------------------------------------------------ EXPOSURE LOGSHEET ID = 3946c [ 4] ------------------------------------------------------------------------------------------------------------------------------------ 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 |10 | 11 | 12 |13 |14| 15 ------------------------------------------------------------------------------------------------------------------------------------ Line | Seq | Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | S/N |Flx|Pr| Special Number | Name | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| |Rel. Time|Ref| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 140 NGC7027- FOS/RD ACQ/ 4.3 MIRROR BRIGHT=300000 1 11S 1 ONBOARD ACQ FOR OFFSET BINARY 140.5 CYCLE 2 Comments: EXPOSURE TIME CALC. FROM ASSUMING REF STAR IS A V=15.3M K0 III STAR ------------------------------------------------------------------------------------------------------------------------------------ 140.5 NGC7027- FOS/RD ACQ/ 1.0 G570H 5250- SEARCH-SIZE=4 1 10S 1 1 ONBOARD ACQ FOR STAR PEAK 5750 SCAN-STEP=0.35 141 CYCLE 2 Comments: T(PEAK) BASED ON CSPN V=16.1 ESTIMATED COUNTS = .8 C/S/D * 10 S * 170 DIODES = 1360 COUNTS PER DWELL POINT OVERHEAD: 4.5 +0.7*4*4 = 15.7M ------------------------------------------------------------------------------------------------------------------------------------ 141 NGC7027- FOS/RD ACCUM 1.0 G400H 1 45M 1 1 CYCLE 2 STAR ------------------------------------------------------------------------------------------------------------------------------------ 142 NGC7027-NEB FOS/RD RAPID 1.0 G400H 1 10M 1 1 CYCLE 2 ------------------------------------------------------------------------------------------------------------------------------------ Summary Form for Proposal 3946c [ 5] Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations FOS/RD ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACQ/BINARY ACQ/PEAK ACCUM RAPID ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters BRIGHT=300000 SEARCH-SIZE=4 SCAN-STEP=0.35 ------------------------------------------------------------------------------------------------------------------------------------ Proposal for GTO/HRS ------------------------------------------------------------------------------------------------------------------------------------ S/C Hours 1.84 ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category STELLAR ASTROPHYSICS ------------------------------------------------------------------------------------------------------------------------------------ Scientific Sub-category SUBLUMINOUS STARS ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ONBOARD ACQ FOR 140.5; CYCLE 2 ONBOARD ACQ FOR 141; CYCLE 2 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements MIRROR G570H G400H ------------------------------------------------------------------------------------------------------------------------------------ Target Names NGC7027-OFFSET NGC7027-STAR NGC7027-NEB ------------------------------------------------------------------------------------------------------------------------------------