In section 7. Stellar structure and evolution
The size, luminosity, and motion of the extreme carbon star IRC+10216 (CW Leonis)
IRC+10216 is a key object for asymptotic giant branch studies. The authors of this article have used the VLA with an angular resolution of 40 milliarcseconds to determine an angular diameter for the star of 83 milliarcseconds (11 AU). On this basis, they conclude that the radio photosphere is roughly twice the size of the optical photosphere and determine much improved values for the proper motion. The latter result has consequences for the interaction of the wind from IRC10216 with the surrounding interstellar medium (the local ISM density and the mass loss rate of the star).