Building upon our previous MHD simulation study of magnetic channeling in radiatively driven stellar winds , we examine here the additional dynamical effects of stellar rotation in the ( still ) 2-D axisymmetric case of an aligned dipole surface field .
In addition to the magnetic confinement parameter \eta _ { \ast } introduced in Paper I , we characterize the stellar rotation in terms of a parameter W \equiv V _ { rot } / V _ { orb } ( the ratio of the equatorial surface rotation speed to orbital speed ) , examining specifically models with moderately strong rotation W = 0.25 and 0.5 , and comparing these to analogous non-rotating cases .
Defining the associated Alfvén radius R _ { A } \approx \eta _ { \ast } ^ { 1 / 4 } R _ { \ast } and Kepler corotation radius R _ { K } \approx W ^ { -2 / 3 } R _ { \ast } , we find rotation effects are weak for models with R _ { A } < R _ { K } , but can be substantial and even dominant for models with R _ { A } \mathrel { \hbox to 0.0 pt { \lower 3.0 pt \hbox { $ \mathchar 536 $ } \hss } % \raise 2.0 pt \hbox { $ \mathchar 318 $ } } R _ { K } .
In particular , by extending our simulations to magnetic confinement parameters ( up to \eta _ { \ast } = 1000 ) that are well above those ( \eta _ { \ast } = 10 ) considered in Paper I , we are able to study cases with R _ { A } \gg R _ { K } ; we find that these do indeed show clear formation of the rigid-body disk predicted in previous analytic models , with however a rather complex , dynamic behavior characterized by both episodes of downward infall and outward breakout that limit the buildup of disk mass .
Overall , the results provide an intriguing glimpse into the complex interplay between rotation and magnetic confinement , and form the basis for a full MHD description of the rigid-body disks expected in strongly magnetic Bp stars like \sigma Ori E .