1301.2778 (Maresuke Shiraishi et al.)

Scale-dependent bias due to primordial vector field    [PDF]

Maresuke Shiraishi, Shuichiro Yokoyama, Kiyotomo Ichiki, Takahiko Matsubara

Anisotropic stress due to primordial Gaussian vector fields creates the non-Gaussianity in curvature perturbation. We newly provide a generation mechanism of the scale-dependent bias induced by such a non-Gaussian source. We find a simple relation between the amplitude of the non-Gaussianity from the vector field and the local-type nonlinearity parameter, and demonstrate its consistency at large scales and tiny deviation at small scales in the scale-dependent bias for several spectral indices of the vector field and redshifts. By interpreting the vector field as the primordial large scale magnetic field, we show that the magnetic field certainly realizes the negative scale-dependent bias. The scale-dependent bias will become a new window on the primordial vector field.

View original: http://arxiv.org/abs/1301.2778