Statistically anisotropic curvature perturbation generated during the
  waterfall
  If the waterfall field of hybrid inflation couples to a U(1) gauge field, the
waterfall can generate a statistically anisotropic contribution to the
curvature perturbation. We investigate this possibility, generalising in
several directions the seminal work of Yokoyama and Soda. The statistical
anisotropy of the bispectrum could be detectable by PLANCK even if the
statistical anisotropy of the spectrum is too small to detect.
