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J/A+A/328/175       K & M giants equivalent widths (Aoki+ 1997)

High resolution infrared spectroscopy of CN and NH lines: nitrogen abundance in oxygen-rich giants through K to late M Aoki W., Tsuji T. <Astron. Astrophys. 328, 175 (1997)> =1997A&A...328..175A (SIMBAD/NED BibCode)
ADC_Keywords: Stars, giant ; Spectra, infrared ; Equivalent widths Keywords: stars: abundances - stars: atmospheres - stars: late-type - stars: AGB and post AGB Abstract: The analyses of high resolution infrared spectra have been done for CN lines in oxygen-rich cool evolved stars including 2 K giants, 20 M giants and 1 S-type star. Since CN lines analyzed in the present work are weak and resolved well, they are appropriate for quantitative analyses. CN lines of {DELTA}v=-2 and -1 sequences (red system) which are in the K- and the H-window regions, respectively, give the consistent nitrogen abundance for each star. The analyses of NH lines in the L-window region have been done for 5 late M giants for which CN lines have been also analyzed. Although the triplet structure of NH lines cannot be fully resolved, they are preferable because determination of nitrogen abundance is almost independent of other elemental abundances while nitrogen abundance based on CN depends on carbon abundance. The nitrogen abundances derived from NH for late M giants agree well with those from CN for which we adopt 7.75eV as the dissociation energy in the analysis. The results show that the nitrogen abundances in late M giants are larger than those in early M giants while decrease of the carbon abundance was found in late M giants by our previous work (Tsuji, 1991A&A...245..203T). These variations of abundances can not be explained by the first dredge-up model but require additional processing by the CN cycle and mixing after the first dredge-up. However, there is no obvious evidence of other processes such as the 3α-process and subsequent hot bottom burning in our program stars. Such variation of the carbon and nitrogen abundances is not well understood by the present evolutionary models of low-mass and intermediate-mass stars. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file tab10ab 56 1463 CN lines in K- and H-windows region in K and early M giants tab10cd 56 1300 CN lines in K- and H-windows region in late M giants tab10e 62 115 NH lines in L-window region in late M type giants
Byte-by-byte Description of file: tab10ab tab10cd
Bytes Format Units Label Explanations
1- 9 A9 --- Name Star name 12 A1 --- Window [HK] Window 14- 23 A10 --- Line Line 25- 32 F8.3 cm-1 WN Wavenumber 34- 39 F6.3 --- log(gf) log of oscillation strength 41- 49 F9.3 cm-1 LEP Lower excitation potential 51- 56 F6.3 [0.1nm] log(EW) ? Equivalent width
Byte-by-byte Description of file: tab10e
Bytes Format Units Label Explanations
1- 7 A7 ---- Name Star name 9- 15 A7 ---- Line Line 17- 24 F8.3 cm-1 WN Wavenumber 26- 34 F9.3 cm-1 LEP Lower excitation potential 36- 41 F6.3 --- log(gf)1 log of oscillation strength (1) 43- 48 F6.3 --- log(gf)2 log of oscillation strength (1) 50- 55 F6.3 --- log(gf)3 log of oscillation strength (1) 57- 62 F6.3 [0.1nm] log(EW) ? Equivalent width
Note (1): The equivalent widths are measured for two or three components of the triplet structure together with the 3 gf values given.
Acknowledgements: Wako Aoki
(End) Patricia Bauer [CDS] 22-Sep-1997
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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