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J/A+A/368/250       Abundances of HDE 341617             (Arellano Ferro+, 2001)

Atmospheric abundances in post-AGB candidates of intermediate temperature Arellano Ferro A., Giridhar S., Mathias P. <Astron. Astrophys. 368, 250 (2001)> =2001A&A...368..250A
ADC_Keywords: Protostars ; Planetary nebulae ; Equivalent widths ; Radial velocities Keywords: stars: post-AGB - stars: chemically peculiar - stars: evolution Abstract: Detailed atmospheric abundances have been calculated for a sample of A-G supergiant stars with IR fluxes and/or high galactic latitudes. HD 172481 and HD 158616 show clear indications of being post-AGB stars that have experienced third dredge-up. HD 158616 is carbon-rich while the abundance pattern of HD 172481 and its large Li enhancement gives support to the hot bottom burning scenario that explains paucity of carbon-rich stars among AGB stars. HD 172324 is very likely a hot post-AGB star that shows a strong carbon deficiency. HD 725, HD 218753 and HD 331319 also appear to be evolved objects between the red giant and the AGB. HD 9167, HD 173638 with a few exceptions, reflect solar abundances and no signs of post red giant evolution. They are most likely young massive disk supergiants. Further analysis of proto-Planetary Nebula HDE 341617 reveals that He lines show signs of velocity stratification. The emission lines have weakened considerably since 1993. The envelope expands at 19km/s relative to the star. Atmospheric abundances, evolutionary tracks and isochrones are used to estimate masses and ages of all stars in the sample. Description: Table 11.dat: Several absorption lines of He I, O II, Si III and Fe II are detected. The radial velocity, for each individual line unambiguously identified is given. For He I two groups of lines are identified at average velocities of 52.6±8.3km/s (4 lines) and 75.0±3.7km/s (4 lines). This suggests some stratification in the atmosphere. The rest of the species however average 73.3±2.9km/s (15 lines). The low dispersion in the radial velocity suggests that all these lines are formed in the same region of the stellar atmosphere and no stratification is evident. Table 12.dat: the emission spectrum, formed in the outer envelope and/or in the nebulosity, consists of lines of Fe II, [Fe II], Fe III, [S II], O I, [N II] and Si II. The radial velocities of emission lines are all very consistent and average 54.3±3.4km/s. The difference of radial velocities between the absorption and emission lines indicates that the nebulosity expands at about 19km/s. The Balmer lines show emission on top of the stellar absorption. The emission is shifted relative to the absorption and is consistent with the radial velocities of other emission features, showing that it is also produced in the same region. Objects: ---------------------------------------------------------- RA (2000) DE Designation(s) ---------------------------------------------------------- 18 08 20.1 +24 10 43 HDE 341617 ---------------------------------------------------------- File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table11.dat 55 27 Absorption lines identified in the spectrum of the proto-Planetary Nebula HDE 341617. table12.dat 56 84 Emission lines identified in the spectrum of the proto-Planetary Nebula HDE 341617 tables.tex 102 182 LaTeX version of the tables
Byte-by-byte Description of file: table11.dat table12.dat
Bytes Format Units Label Explanations
1- 14 A14 --- Ion Ion designation 16- 23 F8.3 0.1nm lambdaObs Observed wavelength 25- 32 F8.3 0.1nm lambdaLab ? Laboratory wavelength (1) 33 A1 --- n_lambdaLab [/+] Note on lambdaLab2 (2) 34- 41 F8.3 0.1nm lambdaLab2 ? Second value of laboratory wavelength (2) 43- 49 F7.2 0.1pm EW ? Equivalent width 51- 55 F5.2 km/s RV ? Radial velocity
Note (1): uf: unidentified feature Note (2): For O II+C III, LambdaLab = 4673.91 /4673.75 For He Ibld, LambdaLab = 5875.618+5875.650 For O I, LambdaLab =5958.46 +5958.630 For O I bld, LambdaLab = 6046.26 +6046.46
Acknowledgements: A. Arellano Ferro
(End) Patricia Bauer [CDS] 19-Jan-2001
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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