H-alpha Spectral Monitoring of epsilon Aurigae 2009–2011 Eclipse
Received February 22, 2012; revised May 30 2012; accepted May 30, 2012
We present and analyze epsilon Aurigae data concerning the evolution of the Ha line on the occasion of the 2009 International observation campaign launched to cover the eclipse of this object. We visually inspect the dynamical spectrum constructed from the data and analyze the evolution with time of the EW (Equivalent Width) and of the radial velocity. The spectroscopic data reveal many details which confirm the complexity of the epsilon Aur system. The object is far from being understood. In particular, according to our measurements, the eclipse duration has been underestimated. A complete analysis of details revealed by our data would require much time and effort. Observers are encouraged to continue monitoring the Ha line out of eclipse in the hope that it will provide further important information.