Intermediate Report on January 2013 Campaign: Photometry and Spectroscopy of P Cygni

Volume 41 number 1 (2013)

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Ernst Pollmann
Emil-Nolde-Str. 12, 51375 Leverkusen, Germany;
Wolfgang Vollman
Dammäckergasse 28/D1/20, 1210 Wien, Austria;


In this campaign on the Luminous Blue Variable star P Cygni, we are trying for the first time, by way of contemporaneous measurements of photometric V brightness and Hα equivalent width (EW), to realize a long-term monitoring of the intrinsic Hα line flux. Photometric and spectroscopic observers started this campaign in November 2008 in order to continue former investigations whose results are based on multi-daily averaging of V and EW. The campaign results enable us to represent the quantitative behavior of the Hα line flux for the time span August 2005 to December 2011, which reflects variabilities in mass-loss rate, stellar wind density, and the ionization structure.