The infrared to gamma-ray pulse shape of the Crab Nebula pulsar

We analyze the pulse shape of the Crab Nebula pulsar in the near-infrared, optical, ultraviolet, X-ray, and gamma-ray bands. We find that the phase separation between the two peaks of the pulse profile decreases nearly continuously as a function of energy over 7 decades of energy. We find that the differences between the energy dependences of the leading and trailing edge half-width half-maxima of both peaks found by Eikenberry et al. (1996a) also continue over 7 decades of energy. We show that the cusped shape of Peak 2 reverses direction between the infrared/optical and X-ray/gamma-ray bands, while the cusped shape of Peak 1 shows weak evidence of reversing direction between the X-ray and gamma-ray bands. These and many other pulse shape parameters are not predicted by current pulsar emission models, and offer new challenges for the development of such models.