English

Ionized bubble number count as a probe of non-Gaussianity

Cosmology and Nongalactic Astrophysics 2015-05-27 v1

Abstract

The number count of ionized bubbles on a map of 21 cm fluctuations with the primordial non-Gaussianity is investigated. The existence of the primordial non-Gaussianity modifies the reionization process, because the formation of collapsed objects, which could be the source of reionization photons, is affected by the primordial non-Gaussianity. In this paper, the abundance of ionized bubbles is calculated by using a simple analytic model with the local type of the primordial non-Gaussianity, which is parameterized by f_{NL}. In order to take into account the dependence of the number count on the size of ionized bubbles and the resolution of the observation instrument, a threshold parameter B_b which is related to the the surface brightness temperature contrast of an ionized bubble is introduced. We show the potential to put the constraint on f_{NL} from the number count by future observations such as LOFAR and SKA.

Keywords

Cite

@article{arxiv.1104.0149,
  title  = {Ionized bubble number count as a probe of non-Gaussianity},
  author = {Hiroyuki Tashiro and Naoshi Sugiyama},
  journal= {arXiv preprint arXiv:1104.0149},
  year   = {2015}
}

Comments

6 pages and 9 figures, submitted to MNRAS