2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/7599It has been noted that the Crab and Vela pulsar proper motions lie along the symmetry axes of their wind nebulae. In an effort to promote this observation to a serious test of kick physics, we are using CXO images and other data to estimate the angle between the proper motion and PWN (i.e. spin) axis for a number of pulsars. Here we give a progress report on this work and the constraints that these data provide on kick models. Present data suggest that a kick duration of tau_K~3s is sufficient to explain the alignment of most pulsars. This rules out E-M and hydrodynamic kick models, but is fairly consistent with proposed anisotropic neutrino emission. However, some objects, especially PSR J0538+2817 show such good alignment that even neutrino models are challenged.To Appear in Proceedings of the 2004 Apsen Winter Conf. on Astrophysics, APS Conf Series, Rasio & Stairs, edsAstrophysicstext