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arXiv · 1411.7701

Statistical Analysis of Interferometric Measurements of Axis Ratios for Classical Be Stars

Richard P. Cyr·Carol E. Jones·Christopher Tycner
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Abstract

This work presents a novel method to estimate the effective opening angle of CBe star disks from projected axis ratio measurements, obtained by interferometry using Bayesian statistics. A Monte Carlo scheme was used to generate a large set of theoretical axis ratios from disk models using different distributions of disk densities and opening angles. These theoretical samples were then compared to observational samples, using a two-sample Kolmogorov-Smirnov test, to determine which theoretical distribution best reproduces the observations. The results suggest that the observed ratio distributions in the K-, H-, and N-band can best be explained by the presence of thin disks, with opening half-angles of the order of 0.15$^{\circ}$ to 4.0$^{\circ}$. Results for measurements over the H$\alpha$ line point toward slightly thicker disks, 3.7$^{\circ}$ to 14$^{\circ}$, which is consistent with a flaring disk predicted by the viscous disk model.

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Richard P. Cyr, Carol E. Jones, Christopher Tycner. 2014-11-27. Statistical Analysis of Interferometric Measurements of Axis Ratios for Classical Be Stars. https://doi.org/10.1088/0004-637x/799/1/33

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