A fundamental step towards the cosmological 21 cm signal

The imprint of warm dark matter on the cosmological 21-cm signal

We investigate the effects of warm dark matter (WDM) on the cosmic 21-cm signal. If dark matter exists as WDM instead of cold dark matter (CDM), its non-negligible velocities can inhibit the formation of low-mass haloes that normally form first in CDM models, therefore delaying star formation. The absence of early sources delays the build-up of UV and X-ray backgrounds that affect the 21-cm rad...

Constraints on Fundamental Cosmological Parameters with Upcoming Redshifted 21 Cm Observations

Constraints on cosmological parameters from upcoming measurements with the Mileura Widefield Array—Low Frequency Demonstrator (MWA-LFD) of the redshifted 21 cm power spectrum are forecast assuming a flat ΛCDM cosmology and that the reionization of neutral hydrogen in the intergalactic medium occurs below a redshift of z = 8. We find that observations with the MWA-LFD cannot constrain the underl...

Cosmic 21-cm Fluctuations as a Probe of Fundamental Physics

Fluctuations in high-redshift cosmic 21-cm radiation provide a new window for observing unconventional effects of high-energy physics in the primordial spectrum of density perturbations. In scenarios for which the initial state prior to inflation is modified at short distances, or for which deviations from scale invariance arise during the course of inflation, the cosmic 21-cm power spectrum ca...

Global 21 cm signal experiments : A designer ’ s guide

21 . The Cosmological Parameters 1 21 . THE COSMOLOGICAL PARAMETERS

Rapid advances in observational cosmology have led to the establishment of a precision cosmological model, with many of the key cosmological parameters determined to one or two significant figure accuracy. Particularly prominent are measurements of cosmic microwave background (CMB) anisotropies, led by the seven-year results from the Wilkinson Microwave Anisotropy Probe (WMAP) [1–3]. However th...