English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Prior to the epoch of reionisation, the 21-cm signal of the cosmic dawn isdominated by the Lyman-$\alpha$ coupling and gas temperature fluctuationscaused by the first sources of radiation. While early efforts to model thisepoch relied on analytical techniques, the community quickly transitioned tomore expensive semi-numerical models. Here, we re-assess the viability ofsimpler approaches that allow for rapid explorations of the vast astrophysicalparameter space. We propose a new analytical method to calculate the 21-cmpower spectrum based on the framework of the halo model. Both theLyman-$\alpha$ coupling and temperature fluctuations are described byoverlapping radiation flux profiles that include spectral red-shifting andsource attenuation due to look-back (light-cone) effects. The 21-cm halo modelis compared to the semi-numerical code 21cmFAST exhibiting generally goodagreement, i.e., the power spectra differ by less than a factor of three over alarge range of $k$-modes and redshifts. We show that the remaining differencesbetween the two methods are comparable to the expected variations frommodelling uncertainties associated with the abundance, bias, and accretionrates of haloes. While these current uncertainties must be reduced in thefuture, our work suggests that inference at acceptable accuracy will becomefeasible with very efficient halo models of the cosmic dawn.

A halo model approach for the 21-cm power spectrum at cosmic dawn