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We present the first high angular resolution observations in the nearinfraredH-band (1.6 microns) of the Luminous Blue Variable star P Cygni. We obtainedsix-telescope interferometric observations with the CHARA Array and the MIRCbeam combiner. These show that the spatial flux distribution is larger thanexpected for the stellar photosphere. A two component model for the star(uniform disk) plus a halo (two-dimensional Gaussian) yields an excellent fitof the observations, and we suggest that the halo corresponds to flux emittedfrom the base of the stellar wind. This wind component contributes about 45% ofthe H-band flux and has an angular FWHM = 0.96 mas, compared to the predictedstellar diameter of 0.41 mas. We show several images reconstructed from theinterferometric visibilities and closure phases, and they indicate a generallyspherical geometry for the wind. We also obtained near-infraredspectrophotometry of P Cygni from which we derive the flux excess compared to apurely photospheric spectral energy distribution. The H-band flux excessmatches that from the wind flux fraction derived from the two component fits tothe interferometry. We find evidence of significant near-infrared fluxvariability over the period from 2006 to 2010 that appears similar to thevariations in the H-alpha emission flux from the wind. Future interferometricobservations may be capable of recording the spatial variations associated withtemporal changes in the wind structure.

The H-band Emitting Region of the Luminous Blue Variable P Cygni: Spectrophotometry and Interferometry of the Wind