Interaction of wide-angle MHD winds with flared disks

A magneto centrifugal mechanism probably underlies the narrow, high-speed, optical jets associated with young stellar objects. Recent theoretical calculations of jet formation in the X-wind model suggest the co-existence of a wide-angle component surrounding the well-collimated jet. We consider whether the predicted wide-angle component can reveal itself through interaction with an underlying flared accretion disk. We use the method of characteristics to calculate numerically the properties of the resulting shockwave. Because the frozen-in magnetic field reduces the effective Mach number of the flow, the shock is too weak at a distance of 10-100 AU to produce [O I] lambda 6300 or [S II] lambda 6717/6731 emission. Unless disks have obstructing features more extreme than conventional flaring (e.g., their own wind), the uncollimated component of an X-wind will remain optically hidden until it impacts material well off the disk plane at larger distances from the central star (e.g., an infalling envelope or the ambient molecular cloud).