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arXiv · 0706.0891

Recent UBVJH Photometry of Epsilon Aurigae

Abstract

Since first observed in the early 1980s, the Hopkins Phoenix Observatory continues its UBV band observations of the long period (27.1 years) eclipsing binary star system epsilon Aurigae. The UBV observations routinely produce standard deviations or data spread better than 0.01 magnitudes many times approaching 0.001 magnitudes. A new infrared photometer has allowed the addition of near-infrared observations for the JH bands. Typical near-infrared observations approach a standard deviation of data spread of 0.01 magnitudes. The 2003 - 2005 seasons (Fall through Spring) of epsilon Aurigae observations showed a 66.2 day variation that gradually increases in average and peak magnitude in the UBV bands. The 2006 season (Fall 2006 to Spring 2007) data show what appears to be a fall-back to a quiet period near maximum amplitude of V= 3.00. This paper presents the data and compares the current season to the past several seasons. The next eclipse is predicted to begin in 2009 and an international campaign has been organized to coordinate new observations. These website links are: [http://www. hposoft.com/Campaign09.html ] and [ http://www.du.edu/~rstencel/epsaur.htm ] .

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BibTeXRIS

Jeffrey L. Hopkins, Robert E. Stencel. 2007-06-06. Recent UBVJH Photometry of Epsilon Aurigae. https://arxiv.org/abs/0706.0891

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