Cooray Asantha
Department of Physics and Astronomy, 4186 Frederick Reines Hall, University of California, Irvine, California 92697, USA.
Phys Rev Lett. 2006 Dec 31;97(26):261301. doi: 10.1103/PhysRevLett.97.261301. Epub 2006 Dec 26.
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 10(5) can limit the primordial non-Gaussianity parameter f(NL) <, similar 0.01.
初始扰动的非高斯性提供了有关产生原初密度涨落机制的信息。我们发现，再电离之前由于中性氢分布不均匀导致的21厘米背景各向异性，比高分辨率宇宙微波背景各向异性图能更好地捕捉原初非高斯性的信息。在14至40兆赫频率范围内进行的全天空21厘米实验，若角分辨率能达到多极矩为10(5)，则可将原初非高斯性参数f(NL)限制在<, 约0.01 。
