The Structure of the Wolf-Rayet Eclipsing Variable V 444 Cygni.

A light-curve at X 7200 made photoelectrically in the years 1943 and 1946 is presented. A solution for elements from our original light-curve at X 4500 and from the new curve is given. This solution indicates that the WoIf-Rayet component consists of a small opaque core, of effective temperature 80,000 K, surrounded by a contiguous thick envelope that is luminous and semitransparent, whose luminosity is a function of wave length. This structure is inclosed by a second much larger envelope, which is inferred to be composed effectively of free electrons. The evidence indicates that the electron envelope must be a relatively thin, hollow shell, probably detached from the inner structure. The optical properties of the electron envelope are independent of wave length. Absolute dimensions and temperatures are given for the various components of the system. The distance is found to be 1500 parsecs after correction for space absorption by means of the color excesses of near-by stars observed by Stebbins, Huffer, and Whitford. Various unconventional features of V 444 Cygui are discussed.