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The results of a spectroscopic survey of epsilon Aurigae during eclipse using a network of small telescopes are presented. The spectra have a resolution of 0.35 to 0.65{AA} and cover the period 2008 to 2012 with a typical interval of 4 days during eclipse. This paper specifically covers variations in the K I 7699{AA}, Na D and Mg II 4481{AA} lines. Absorption started increasing in the KI 7699{AA} line 3 months before the eclipse began photometrically and had not returned to pre eclipse levels by the end of the survey March 2012, 7 months after the brightness had returned to normal outside eclipse levels. The contribution of the eclipsing object to the KI 7699{AA} line has been isolated and the data show the excess absorption increasing and decreasing in a series of steps during ingress and egress. This is interpreted as an indication of structure within the eclipsing object. The F star is totally obscured by the eclipsing object at the Na D wavelength during eclipse. The radial velocity of the F star and the mean and maximum radial velocity of the eclipsing material in front of the F star at any given time have been isolated and tracked throughout the eclipse. The quasi-periodic variations seen in the F star RV outside eclipse continued during the eclipse. It is hoped that these results can be used to constrain proposed models of the system and its components.
We present and analyze epsilon Aurigae data concerning the evolution of the H$alpha$ line on the occasion of the 2009 International observation campaign launched to cover the eclipse of this object. About 250 high resolution spectra of the H$alpha$ l
A series of 353 red electronic spectra obtained between 1994 and 2010, and of 171 UBV photometric observations of the 2010 eclipse, were analyzed in an effort to better understand the eclipsing binary eps Aur. The main results follow. (1) We attempte
A single-epoch low resolution GHRS spectrum of the eclipsing binary Epsilon Aurigae was obtained while the secondary was orbiting towards eclipse by the primary. The detected emission line profiles have the appearance of double- peaked emission with
We report on a total of 106 nights of optical interferometric observations of the $epsilon$ Aurigae system taken during the last 14 years by four beam combiners at three different interferometric facilities. This long sequence of data provides an ide
We collected rich series of RV measurements covering last 110 years and photometric observations from the past 6 primary eclipses, complemented them by our new observations and derived a new precise ephemeris and an orbital solution of epsilon Aur.