Proto-Neutron Star Winds, Magnetar Birth, and Gamma-Ray Bursts

We begin by reviewing the theory of thermal, neutrino-driven proto-neutron star (PNS) winds. Including the effects of magnetic fields and rotation, we then derive the mass and energy loss from magnetically-driven PNS winds for both relativistic and non-relativistic outflows, including important multi-dimensional considerations. With these simple analytic scalings we argue that proto-magnetars born with ~ millisecond rotation periods produce relativistic winds just a few seconds after core collapse with luminosities, timescales, mass-loading, and internal shock efficiencies favorable for producing long-duration gamma-ray bursts.