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arXiv · 1204.5901

A study of the role of Lyman {\beta} fluorescence on OI line strengths in Be stars

Blesson Mathew·Dipankar P. K. Banerjee·Annapurni Subramaniam·N. M. Ashok
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Abstract

The possibility of the Ly{\beta} fluorescence mechanism being operational in classical Be stars and thereby contributing to the strength of the OI 8446 {\AA} line has been recognized for long. However this supposition needs to be quantified by comparing observed and predicted OI line ratios. In the present work, optical and near-infrared spectra of classical Be stars are presented. We analyse the observed strengths of the OI 7774, 8446, 11287 and 13165 {\AA} lines which have been theoretically proposed as diagnostics for identifying the excitation mechanism. We have considered and examined the effects of Ly{\beta} fluorescence, collisional excitation, recombination and continuum fluorescence on these OI line strengths. From our analysis it appears that the Ly{\beta} fluorescence process is indeed operative in Be stars.

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Blesson Mathew, Dipankar P. K. Banerjee, Annapurni Subramaniam, N. M. Ashok. 2012-04-26. A study of the role of Lyman {\beta} fluorescence on OI line strengths in Be stars. https://doi.org/10.1088/0004-637x/753/1/13

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