Page 1 PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID 5690 Report Date: 18-Jul-95:17:51 Version: ********** Check-in Date: ********** 1.Proposal Title: ULTRAVIOLET SPECTROSCOPY OF HYDROGEN-POOR PLANETARY NEBULAE CYCLE 4 CARRYOVER ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Proposal Type 5. Continuation ID INTERSTELLAR MEDIUM GO/CAR 4226 Sub Category PLANETARY NEBULAE ------------------------------------------------------------------------------------ 6. Principal Investigator Institution Country Telephone Patrick Harrington UNIVERSITY OF MARYLAND, DEPT USA 301-405-6266 ------------------------------------------------------------------------------------ 7. Abstract Planetary nebulae (PNe) form in the final stages of evolution of intermediate- and low-mass stars, and show abundances consistent with contamination by modest amounts of processed material. There is however an exceptional group of PNe with nebular gas that consists of nearly undiluted products of nuclear burning. These hydrogen-poor PNe are thought to result when a final helium shell flash occurs after the complete removal of the hydrogen envelope. We propose to study 2 of the 6 currently known H-poor PNe with HST. The best studied object, Abell 30, shows that the majority of the emission line radiation is in the UV, and thus UV spectrophotometry is indispensable for quantitative analysis. Our proposed HST observations (in conjunction with our ground based work) will provide fundamental information (1) on helium-burning nucleosynthesis, by determining the ionic concentrations of H and He burning products; (2) on the physics of very dusty gas, by determining the energy balance; this is crucial since it now appears that due to the high dust-to-gas ratio, the energy input may be partially, and in some cases, primarily, due to photoelectric ejection by grains rather than by photoionization; and (3) on the interaction of the several thousand km/sec stellar winds with the nearby clumps of nebular material, by analysis of the velocity structure of the C IV 1550 line. ------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------ 9. Est obs time (hours) pri: 6.96 par: 0 10. Num targs pri: 2 par: 0 ------------------------------------------------------------------------------------ 11. Instruments requested: FOS ------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------ Page 2 I. GENERAL FORM Proposal 5690 PI: Patrick Harrington Proposal Title: ULTRAVIOLET SPECTROSCOPY OF HYDROGEN-POOR PLANETARY NEBULAE CYCLE 4 CARRYOVER ------------------------------------------------------------------------------------ 1. Proposers: Proposers Institution Country ESA ------------------------------------------------------------------------------------ Pi Patrick Harrington UNIVERSITY OF MARYLAND, DEPT. OF USA ASTRONOMY, COLLEGE PARK Kazimierz J Borkowski UNIVERSITY OF MARYLAND, DEPT. OF USA ASTRONOMY, COLLEGE PARK Robin E Clegg ROYAL GREENWICH OBSERVATORY, UK X CAMBRIDGE Zlatan Tsvetanov JOHNS HOPKINS U., DEPT. PHYSICS USA AND ASTRONOMY, BALTIMORE ------------------------------------------------------------------------------------ 3. Description of proposed observations. We plan to take O III images in the optical to obtain a comparable spatial resolution in this wavelength range. A comparison of optical and UV images should be interesting in view of differences in optical and UV spectra mentioned previously. The optical spectra of the two brightest emission knots in A30 (knots 3 and 4, Jacoby & Ford 1983) differ significantly. We chose these knots for UV spectroscopy with the FOS and the blue digicon. We plan to obtain UV spectra with the large 4''.3 aperture in the high-resolution mode in order to obtain a good S/N ratio and not to degrade spectral resolution excessively due to the finite extent of the knots. Positions of spectroscopic apertures in the fainter Galactic nebulae, the M22 PN were chosen on the basis of high-resolution O III images taken with the New Technology Telescope in La Silla. In both cases bright knots of emission can be seen in the east. We will take far-UV, low- resolution (G160L) FOS spectra of these knots, with the one arcsec aperture in the M22 nebula. An investigation of the stellar wind from the central star of the M22 PN, predicted theoretically to be dynamically important in the interaction of this nebula with the ISM, will be pursued by taking a high-resolution, far-UV FOS spectrum of the star through the large 4''.3 aperture. (Edited from original proposal 4226 to contain only the descriptions of the obervations that are being carried-over. Bullock) ------------------------------------------------------------------------------------ 4. Justification of need for HST observations. The thrust of our efforts is concentrated in the UV, and requires space observations. A30, A78, and the M22 PN were extensively studied by the IUE satellite. Multi-hour exposures of A30 (Harrington & Feibelman 1984; Harrington 1986), A78 (Kaler, Feibelman, & Henrichs 1988), and M22 (Cohen & Gillett 1989) pushed the IUE to the limits and provided us with basic information about UV properties of these objects. This information is the basis for the current proposal. Further progress can now be made only with the HST, with its superior spatial resolution and with the much larger gathering power. The two recently discovered hydrogen-poor PNe, LMC 26 and IRAS 15154-5258, can be studied only with the HST because of their relative faintness. Note that our proposal concentrates on UV spectroscopy which suffered relatively little from problems connected with the spherical aberration of the primary mirror. We have started a ground-based observational program to support this project. The high-resolution, continuum subtracted O III images of the M22 PN and IRAS 15154-5258 have been already used to locate bright emission knots to be observed by the HST. We have also obtained spectroscopic data for IRAS 15154-5258, confirming high (T > 20,000 K) electron temperature and refining the interstellar reddening. We used these data to estimate the exposure time for this object. Further observational and theoretical work in support of this project is in progress. Page 3 ------------------------------------------------------------------------------------ 5. Description of special scheduling requirements. ------------------------------------------------------------------------------------ 6. Description of special calibration exposures. ------------------------------------------------------------------------------------ 8. Additional comments or special requests. ------------------------------------------------------------------------------------ 9. Description of previous HST work. No. 2266: Post-Asymptotic Giant Branch Evolution in the Magellanic Clouds, PI M.A. Dopita, P. Harrington is a Co-I. Not related beyond the fact that both deal with planetary nebulae. ------------------------------------------------------------------------------------ 10. Resources to be supplied by investigator's institution(s). The Department of Astronomy of the University of Maryland has an extensive network of Sun workstations, including a number of Sparc II's, as well as a Multiflow mini-super computer. This network and supporting technical staff provides an excellent environment for data reduction and modeling. ------------------------------------------------------------------------------------ 11. Address Information Name: PATRICK HARRINGTON Category: PI Institution: UNIVERSITY OF MARYLAND, DEPT. OF Address: City: COLLEGE PARK State: MD Zip Code: 20742 Country: USA Telephone: (301) 405-1517 Telex (or e-mail): 710-826-0352 ------------------------------------------------------------------------------------ TARGET LIST a) Fixed Targets ID = 5690 [ 4] ------------------------------------------------------------------------------------------------------------------------------------ 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| | | | | | | | | ------------------------------------------------------------------------------------------------------------------------------------ 1 PK208+33D1 G,502,A,184 PLATE-ID=03DI, 2000 V = +10 1 V=14.30+/- ABELL30 RA = 8H 46M 53.46S +/- 2 0.01,TYPE=OVI,A(V)=0.90+/-0.10 GSC1396-1621 0.02S, 3 SURF-LINE(5007) = 9 +/- 2 E-14 DEC = +17D 52' 45.7" +/- 4 SURF-LINE(1550) = 30 +/- 5 E-15 0.3" 5 W-LINE(5007) = 0.17 +/- 0.03 6 W-LINE(1550) = 1.6 +/- 0.2 7 SIZE = 0.2 SIZE = 0.5 Comments: FLUXVAL_1 REFERS TO CENTRAL STAR. LINE INFORMATION FOR EMISSION KNOTS ------------------------------------------------------------------------------------------------------------------------------------ 2 PK208+33D1- A,184 PLATE-ID=03DI, 2000 V = +10 1 V=14.30+/-0.01, TYPE=OVI OFFSET RA = 8H 46M 53.46S +/- 2 B-V=-0.07+/-0.01 ABELL30- 0.02S, 3 E(B-V)=0.30+/-0.03 CENTRAL-STAR DEC = +17D 52' 45.7" +/- -OFFSET 0.3" GSC1396-1621 -OFFSET ------------------------------------------------------------------------------------------------------------------------------------ 3 PK208+33D1- G,502,927 R = 6.61", 2000 1 SURF-LINE(5007) = 10 +/- 2 E-14 KNOT3 PA = 329.7D, 2 SURF-LINE(1550) = 20 +/- 3 E-15 ABELL30- FROM 2 3 W-LINE(1550) = 1.6 +/- 0.2 KNOT3 4 W-LINE(5007) = 0.17 +/- 0.03 5 SURF-LINE(1909) = 30 +/- 4 E-16 6 W-LINE(1909) = 1.0 +/- 0.2 ------------------------------------------------------------------------------------------------------------------------------------ 4 PK208+33D1- G,502,927 R = 3.53", 2000 1 SURF-LINE(5007) = 8 +/- 2 E-14 KNOT4 PA = 221.7D, 2 SURF-LINE(1550) = 16 +/- 3 E-15 ABELL30- FROM 2 3 W-LINE(1550) = 1.6 +/- 0.2 KNOT4 4 W-LINE(5007) = 0.17 +/- 0.03 5 SURF-LINE(1909) = 20 +/- 3 E-16 6 W-LINE(1909) = 1.0 +/- 0.2 7 SURF-LINE(2423) = 25 +/- 4 E-15 8 W-LINE(2423) = 0.17 +/- 0.03 ------------------------------------------------------------------------------------------------------------------------------------ 8 IRAS1833- A,184,C,201 RA = 18H 36M 22.78S +/- 2000 V = -153 COMP 1 V=14.3+/-0.2,TYPE=O 2357-CENTRAL 0.02S, 2 B-V=0.5+/-0.1 -STAR DEC = -23D 55' 19.26" +/- 3 E(B-V)=0.5+/-0.05 0.3" 4 F-CONT(1550) = 45 +/- 10 E-15 Comments: COMPANION RED STAR 1" TO NORTH ------------------------------------------------------------------------------------------------------------------------------------ 9 IRAS1833- G,502,927,C,201 R = 2.3", 2000 V = -153 1 SURF-LINE(1550) = 80 +/- 20 E-17 2357-KNOT PA = 77D, 2 W-LINE(1550) = 0.17 +/- 0.03 FROM 8 Comments: EXPECTED FLUX. ------------------------------------------------------------------------------------------------------------------------------------ EXPOSURE LOGSHEET ID = 5690 [ 5] ------------------------------------------------------------------------------------------------------------------------------------ 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 ------------------------------------------------------------------------------------------------------------------------------------ 1.3 PK208+33D1- FOS/BL ACQ/ 4.3 MIRROR 1 1.05S 17 1 1 CYCLE 4 /1.3-3.2 OFFSET BINARY 2 ONBOARD ACQ FOR 3 1.31-1.43 GROUP 1.30 - 1.43 NO GAP ------------------------------------------------------------------------------------------------------------------------------------ 1.31 PK208+33D1- FOS/BL ACCUM 1.0 G130H 1 51M 3 2 1 KNOT3 3 ------------------------------------------------------------------------------------------------------------------------------------ 1.32 PK208+33D1- FOS/RD ACCUM 1.0 G190H 1 30M 15 5 1 KNOT3 6 ------------------------------------------------------------------------------------------------------------------------------------ 1.33 PK208+33D1- FOS/RD ACCUM 1.0 G270H 1 30M 15 5 1 KNOT3 6 ------------------------------------------------------------------------------------------------------------------------------------ 1.41 PK208+33D1- FOS/BL ACCUM 1.0 G130H 1 51M 30 2 1 KNOT4 3 ------------------------------------------------------------------------------------------------------------------------------------ 1.42 PK208+33D1- FOS/RD ACCUM 1.0 G190H 1 30M 15 5 1 KNOT4 6 ------------------------------------------------------------------------------------------------------------------------------------ 1.43 PK208+33D1- FOS/RD ACCUM 1.0 G270H 1 30M 15 7 2 KNOT4 8 ------------------------------------------------------------------------------------------------------------------------------------ 3 IRAS1833- FOS/BL ACQ/ 4.3 MIRROR 1 1.65S 17 1 1 ONBOARD ACQ FOR 2357- BINARY 2 3.1-3.2 CENTRAL- 3 Comments: CLOSE COMPANION 1" TO NORTH. ------------------------------------------------------------------------------------------------------------------------------------ 3.1 IRAS1833- FOS/BL ACCUM 1.0 G130H 1 20M 17 4 2 2357- CENTRAL- ------------------------------------------------------------------------------------------------------------------------------------ 3.2 IRAS1833- FOS/BL ACCUM 1.0 G160L 1 40M 5 1 1 2357-KNOT 2 ------------------------------------------------------------------------------------------------------------------------------------ Summary Form for Proposal 5690 [ 6] Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Configurations FOS/BL FOS/RD ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACQ/BINARY ACCUM ------------------------------------------------------------------------------------------------------------------------------------ Optional Parameters ------------------------------------------------------------------------------------------------------------------------------------ Proposal for GO/CAR ------------------------------------------------------------------------------------------------------------------------------------ S/C Hours 6.96 ------------------------------------------------------------------------------------------------------------------------------------ Scientific Category INTERSTELLAR MEDIUM ------------------------------------------------------------------------------------------------------------------------------------ Scientific Sub-category PLANETARY NEBULAE ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements CYCLE 4 /1.3-3.2; ONBOARD ACQ FOR 1.31-1.43; GROUP 1.30 - 1.43 NO GAP ONBOARD ACQ FOR 3.1-3.2 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements MIRROR G130H G190H G270H G160L ------------------------------------------------------------------------------------------------------------------------------------ Target Names PK208+33D1 ABELL30 GSC1396-1621 PK208+33D1-OFFSET ABELL30-CENTRAL-STAR-OFFSET GSC1396-1621-OFFSET PK208+33D1-KNOT3 ABELL30-KNOT3 PK208+33D1-KNOT4 ABELL30-KNOT4 IRAS1833-2357-CENTRAL-STAR IRAS1833-2357-KNOT ------------------------------------------------------------------------------------------------------------------------------------