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arXiv · 1807.04221

A Study of H$\alpha$ Line Profile Variations in $\beta$ Lyr

Richard Ignace·Sharon Gray·Macon Magno·Gary Henson·Derck Massa
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Abstract

We examine over 160 archival H$\alpha$ spectra from the Ritter Observatory for the interacting binary $\beta$~Lyr obtained between 1996 and 2000. The emission is characteristically double-peaked, but asymmetric, and with an absorption feature that is persistently blueshifted. Using a set of simplifying assumptions, phase varying emission line profiles are calculated for H$\alpha$ formed entirely in a Keplerian disk, and separately for the line formed entirely from an off-center bipolar flow. However, a dynamic spectrum of the data indicate the blueshifted feature is not always present, and the data are even suggestive of a drift of the feature in velocity shift. We explore whether a circumbinary envelope, hot spot on the accretion disk, or accretion stream could explain the observations. While none are satisfactory, an accretion stream explanation is somewhat promising.

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Richard Ignace, Sharon Gray, Macon Magno, Gary Henson, Derck Massa. 2018-07-11. A Study of H$\alpha$ Line Profile Variations in $\beta$ Lyr. https://doi.org/10.3847/1538-3881%2Faad339

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