Analytical and numerical models of P Cygni’s nebula

We present an analytical model and perform hydrodynamical simulations to study the formation and dynamical evolution of P Cygni's nebula. In the 1600s, the massive star P Cygni underwent an eruptive event, when a total kinetic energy E-k similar to 2 x 10(46) erg was expelled into the underlying stellar wind. The ensuing collision between the outburst and the stellar wind produced a present-day 10 arcsec nebula that, at a distance of 1.7 kpc, represents a physical size of similar to 2.5 x 10(17) cm. This nebula is expanding roughly isotropically at a speed of similar to 140 km s(-1). On the other hand, the historical light curve of the star shows an increase of its visual magnitude that lasted similar to 50 yr in the 17th century. We show through an analytical model that an outburst of shorter duration (similar to 10 yr) is able to explain the dynamics of the nebula. In addition, we investigate through numerical simulations whether the interaction of the 1600s eruption of P Cyg with the pre-eruptive wind can explain not only the morphology and kinematics of the nebula, but also some observed features, such as knots and corrugations, that may result from Rayleigh-Taylor instabilities along the dense shell. We found that our theoretical predictions reproduce successfully the observed overall physical properties of the nebula around P Cygni.