2002/10/01 by Yakiv V. Pavlenko, Y. V. Pavlenko, H. R. A. Jones +1 · 34 citations
Physics and Astronomy · #Astronomy and Astrophysical Research #Carbon fibers #Carbon monoxide #Contamination #Resolution (logic) #Scientific Research and Discoveries #Spectral line #Spectral resolution #Stellar, planetary, and galactic studies #Water vapor #Wavelength #astro-ph
paper · pdf · doi:10.1051/0004-6361:20021454
published in Astronomy and Astrophysics 396(3), 967-975 (EDP Sciences) · 9 pages, 10 figs, accepted by AA
arxiv created 2002/10/01 · openalex publication_date 2002/12/01 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We compare the observational and theoretical spectra of the CO bands in a range of M dwarfs. We investigate the dependence of theoretical spectra on effective temperatures as well as carbon abundance. In general we find that the synthetic CO bands fit the observed data extremely well and are excellent diagnostics. In particular the synthetic spectra reasonably match observations and the best fit temperatures are similar to those found by empirical methods. We also examine the 12C/13C isotopic ratio. We find that fundamental 13CO bands around 2.345 and 2.375 μm are good discriminators for the 12C/13C ratio in M dwarfs. The 2.375 μm band is more useful because it doesn't suffer such serious contamination by water vapour transitions. Our current dataset does not quite have the wavelength coverage to perform a reliable determination of the 12C/13C ratio in M dwarfs. For this we recommend observing the region 2.31–2.40 μm at a resolution of better than 1000. Alternatively the observational problems of contamination by water vapour at 2.345 μm maybe solved by observing at resolutions of around 50 000. We also investigated the possibility of using the = 1 CO bands around 4.5 μm. We find that the contamination due to water vapour is even more of a problem at these wavelengths.