21-cm Background Anisotropies Can Discern Primordial Non-Gaussianity
Abstract
The non-Gaussianity of initial perturbations provides information on the mechanism that generated primordial density fluctuations. We find that 21-cm background anisotropies due to inhomogeneous neutral hydrogen distribution prior to reionization captures information on primordial non-Gaussianity better than a high-resolution cosmic microwave background anisotropy map. An all-sky 21-cm experiment over the frequency range from 14 to 40 MHz with angular information out to a multipole of 105 can limit the primordial non-Gaussianity parameter fNL≲0.01.
- Publication:
-
Physical Review Letters
- Pub Date:
- December 2006
- DOI:
- 10.1103/PhysRevLett.97.261301
- arXiv:
- arXiv:astro-ph/0610257
- Bibcode:
- 2006PhRvL..97z1301C
- Keywords:
-
- 98.70.Vc;
- 98.65.Dx;
- 98.80.Cq;
- 98.80.Es;
- Background radiations;
- Superclusters;
- large-scale structure of the Universe;
- Particle-theory and field-theory models of the early Universe;
- Observational cosmology;
- Astrophysics
- E-Print:
- 4 pages, 1 figure