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arXiv · 1301.2778

Scale-dependent bias due to primordial vector fields

Maresuke Shiraishi·Shuichiro Yokoyama·Kiyotomo Ichiki·Takahiko Matsubara
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Abstract

Anisotropic stress perturbations induced by primordial Gaussian vector fields create non-Gaussianity in curvature perturbations. We found that such non-Gaussianity closely resembles the local-type non-Gaussianity parametrized by $f_{\rm NL}$, and generates scale-dependent bias in large-scale structures. We also found a simple relationship between the scale-dependent bias and the power spectrum of the vector fields. When the vector fields are interpreted as primordial magnetic fields, the effective $f_{\rm NL}$ is shown to be always negative. The scale-dependent bias provides a new approach to probing primordial vector fields.

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Maresuke Shiraishi, Shuichiro Yokoyama, Kiyotomo Ichiki, Takahiko Matsubara. 2013-05-11. Scale-dependent bias due to primordial vector fields. https://doi.org/10.1093/mnras%2Fstt594

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