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J/ApJ/659/1265   Emission lines in 4 planetary nebulae    (Sharpee+, 2007)

s-Process abundances in planetary nebulae. Sharpee B., Zhang Y., Williams R., Pellegrini E., Cavagnolo K., Baldwin J.A., Phillips M., Liu X.-W. <Astrophys. J., 659, 1265-1290 (2007)> =2007ApJ...659.1265S
ADC_Keywords: Planetary nebulae ; Abundances Keywords: ISM: abundances - nuclear reactions, nucleosynthesis, abundances - planetary nebulae: general Abstract: The s-process should occur in all but the lower mass progenitor stars of planetary nebulae, and this should be reflected in the chemical composition of the gas that is expelled to create the current planetary nebula shell. Weak forbidden emission lines are expected from several s-process elements in these shells and have been searched for and in some cases detected in previous investigations. Here we extend these studies by combining very high signal-to-noise ratio echelle spectra of a sample of PNe with a critical analysis of the identification of the emission lines of Z>30 ions. Emission lines of Br, Kr, Xe, Rb, Ba, and Pb are detected with a reasonable degree of certainty in at least some of the objects studied here, and we also tentatively identify lines from Te and I, each in one object. The strengths of these lines indicate enhancement of s-process elements in the central star progenitors, and we determine the abundances of Br, Kr, and Xe, elements for which atomic data relevant for abundance determination have recently become available. As representative elements of the "light" and "heavy" s-process peaks, Kr and Xe exhibit similar enhancements over solar values, suggesting that PN progenitors experience substantial neutron exposure. Description: We obtained spectra of the PNe IC 2501, IC 4191, and NGC 2440 during two observing runs of two nights each in early 2003 using the Las Campanas Observatory (LCO) Baade 6.5m telescope with the MIKE echelle spectrograph. NGC 7027 was observed on four nights in 2002 June with the Mayall 4m Telescope at Kitt Peak National Observatory (KPNO) using the Cassegrain echelle spectrograph. Objects: ---------------------------------------------------------- RA (2000) DE Designation(s) ---------------------------------------------------------- 09 38 47.2 -60 05 31 IC 2501 = PN G281.0-05.6 13 08 47.3 -67 38 38 IC 4191 = PN G304.5-04.8 07 41 54.9 -18 12 30 NGC 2440 = PN G234.8+02.4 21 07 01.6 +42 14 10 NGC 7027 = PN G084.9-03.4 ---------------------------------------------------------- File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table6.dat 79 3087 Emission-Line identifications and intensities
See also: V/84 : Strasbourg-ESO Catalogue of Galactic Planetary Nebulae (Acker+, 1992) Byte-by-byte Description of file: table6.dat
Bytes Format Units Label Explanations
1- 8 A8 --- PN PN name 10- 17 F8.2 0.1nm lambda Observed wavelength 19- 24 F6.2 km/s FWHM Line FWHM 26- 34 F9.4 ---- Flux Flux normalized to Hbeta=100 36- 44 F9.4 ---- Int Integrated flux normalized to Hbeta=100 46- 52 F7.1 --- S/N Signal-to-noise ration 55- 65 A11 --- Line Line identification 66- 74 F9.2 0.1nm lambdaL ? Line Wavelength 76- 79 A4 --- Notes Notes (1)
Note (1): Notes as follows: : = uncertain identification ? = uncertain feature bl = line blend ns = blend with night-sky line
History: From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 25-Jan-2009
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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