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تسجيل مستخدم جديدThe Spatially Resolved Halpha-Emitting Wind Structure of P Cygni
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High spatial resolution observations of the Halpha-emitting wind structure associated with the Luminous Blue Variable star P Cygni were obtained with the Navy Prototype Optical Interferometer (NPOI). These observations represent the most comprehensive interferometric data set on P Cyg to date. We demonstrate how the apparent size of the Halpha-emitting region of the wind structure of P Cyg compares between the 2005, 2007 and 2008 observing seasons and how this relates to the Halpha line spectroscopy. Using the data sets from 2005, 2007 and 2008 observing seasons, we fit a circularly symmetric Gaussian model to the interferometric signature from the Halpha-emitting wind structure of P Cyg. Based on our results we conclude that the radial extent of the Halpha-emitting wind structure around P Cyg is stable at the 10% level. We also show how the radial distribution of the Halpha flux from the wind structure deviates from a Gaussian shape, whereas a two-component Gaussian model is sufficient to fully describe the Halpha-emitting region around P Cyg.
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