Can I read A New Light on 21 Cm Intensity Fluctuations from the Dark Ages on EtoBox?

A New Light on 21 Cm Intensity Fluctuations from the Dark Ages by Ali-Haïmoud, Yacine; Meerburg, P. Daniel; Yuan, Sihan is a scholarly article available to read on EtoBox.

What is A New Light on 21 Cm Intensity Fluctuations from the Dark Ages about?

Fluctuations of the 21 cm brightness temperature before the formation of the first stars hold the promise of becoming a high-precision cosmological probe in the future. The growth of over densities is very well described by perturbation theory at that epoch and the signal can in principle be predicted to arbitrary accuracy for given cosmological parameters. Recently, Tseliakhovich and Hirata pointed out a previously neglected and important physical effect, due to the fact that baryons and cold dark matter (CDM) have supersonic relative velocities after recombination. This relative velocity suppresses the growth of matter fluctuations on scales $k \sim 10-10^3$ Mpc$^{-1}$. In addition, the amplitude of the small-scale power spectrum is modulated on the large scales over which the relative velocity varies, corresponding to $k \sim 0.005-1$ Mpc$^{-1}$. In this paper, the effect of the relative velocity on 21 cm brightness temperature fluctuations from redshifts $z \geq 30$ is computed. We show that the 21 cm power spectrum is affected on ${\it most}$ scales. On small scales, the signal is typically suppressed several tens of percent, except for extremely small scales ($k \gtrsim 2000$

Author

Ali-Haïmoud, Yacine; Meerburg, P. Daniel; Yuan, Sihan

Published

2013

Language

EN