SIMBAD references

2016ApJ...830..159N - Astrophys. J., 830, 159-159 (2016/October-3)

Carbon-to-oxygen ratios in M dwarfs and solar-type stars.

NAKAJIMA T. and SORAHANA S.

Abstract (from CDS):

It has been suggested that high C/O ratios (>0.8) in circumstellar disks lead to the formation of carbon-dominated planets. Based on the expectation that elemental abundances in the stellar photospheres give the initial abundances in the circumstellar disks, the frequency distributions of C/O ratios of solar-type stars have been obtained by several groups. The results of these investigations are mixed. Some find C/O > 0.8 in more than 20% of stars, and C/O > 1.0 in more than 6%. Others find C/O > 0.8 in none of the sample stars. These works on solar-type stars are all differential abundance analyses with respect to the Sun and depend on the adopted C/O ratio in the Sun. Recently, a method of molecular line spectroscopy of M dwarfs, in which carbon and oxygen abundances are derived respectively from CO and H2O lines in the K band, has been developed. The resolution of the K-band spectrum is 20,000. Carbon and oxygen abundances of 46 M dwarfs have been obtained by this nondifferential abundance analysis. Carbon-to-oxygen ratios in M dwarfs derived by this method are more robust than those in solar-type stars derived from neutral carbon and oxygen lines in the visible spectra because of the difficulty in the treatment of oxygen lines. We have compared the frequency distribution of C/O distributions in M dwarfs with those of solar-type stars and have found that the low frequency of high-C/O ratios is preferred.

Abstract Copyright: © 2016. The American Astronomical Society. All rights reserved.

Journal keyword(s): stars: abundances - stars: low-mass - stars: low-mass

Simbad objects: 45

goto Full paper

goto View the reference in ADS

To bookmark this query, right click on this link: simbad:2016ApJ...830..159N and select 'bookmark this link' or equivalent in the popup menu


2020.11.25-14:47:05

© Université de Strasbourg/CNRS

    • Contact