English

The cosmic microwave background temperature bispectrum from scalar perturbations induced by primordial magnetic fields

Cosmology and Nongalactic Astrophysics 2009-10-02 v2

Abstract

We evaluate the angular bispectrum of the CMB temperature anisotropy at large angular scale due to a stochastic background of primordial magnetic fields. The shape of non-Gaussianity depends on the spectral index of the magnetic field power spectrum and is peaked in the squeezed configuration for a scale-invariant magnetic spectrum. By using the large angular part of the bispectrum generated by magnetic fields, the present bounds on non-Gaussianity set a limit on the amplitude of the primordial magnetic field of the order of 10 nGauss for the scale-invariant case and 20 nGauss for the other spectral indexes.

Keywords

Cite

@article{arxiv.0903.1420,
  title  = {The cosmic microwave background temperature bispectrum from scalar perturbations induced by primordial magnetic fields},
  author = {Chiara Caprini and Fabio Finelli and Daniela Paoletti and Antonio Riotto},
  journal= {arXiv preprint arXiv:0903.1420},
  year   = {2009}
}

Comments

Replaced with revised version accepted for publication in JCAP