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arXiv · 1008.3817

A Renaissance study of Am stars. I. The mass ratio distribution

Henri M. J. Boffin
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Abstract

Triggered by the study of Carquillat & Prieur (2007, MNRAS, 380, 1064) of Am binaries, I reanalyse their sample of 60 orbits to derive the mass ratio distribution (MRD), assuming as they did a priori functional forms, i.e. a power law or a Gaussian. The sample is then extended using orbits published by several groups and a full analysis of the MRD is made, without any assumption on the functional form. I derive the MRD using a Richardson-Lucy inversion method, assuming a fixed mass of the Am primary and randomly distributed orbital inclinations. Using the large sub-sample of double-lined spectroscopic binaries, I show that this methodology is indeed perfectly adequate. Using the inversion method, applied to my extended sample of 162 systems, I find that the final MRD can be approximated by a uniform distribution.

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Henri M. J. Boffin. 2010-08-23. A Renaissance study of Am stars. I. The mass ratio distribution. https://doi.org/10.1051/0004-6361/201015529

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