Scholarlink

Abstract <p>The cosmic microwave background absorption intensity in the 21 cm line of neutral hydrogen in the presence of additional power in the form of a ‘‘bump’’ in the spectrum of cosmological density perturbations is calculated. The main absorption-amplifying effect is the earlier birth of the first stars forming an ultraviolet radiation background. This radiation reduces the spin temperature of neutral hydrogen and, thus, amplifies the absorption in the 21 cm line. A comparison of various cosmological models (with and without a bump in the density perturbation spectrum) shows that it is possible to determine the probable position of the bump in the perturbation spectrum and, thus, to reconstruct the spectrum of cosmological perturbations on scales <InlineEquation ID="IEq3"> <EquationSource Format="TEX">\(k&gt;1\)</EquationSource> <!--Letters2570034Eroshenko-m3--> </InlineEquation> Mpc<InlineEquation ID="IEq4"> <EquationSource Format="TEX">\({}^{-1}\)</EquationSource> <!--Letters2570034Eroshenko-m4--> </InlineEquation> from the position of the absorption frequency profile.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Absorption in the 21 cm Hydrogen Line at \(\boldsymbol{z>10}\) as a Sensitive Tool for the Construction of a Cosmological Model on Small Scales

  • 期刊论文

  • 发表日期：

    2025年4月1日

查看全文
  • Yu. N. Eroshenko,
  • V. N. Lukash,
  • E. V. Mikheeva,
  • S. V. Pilipenko,
  • M. V. Tkachev

摘要

Abstract

The cosmic microwave background absorption intensity in the 21 cm line of neutral hydrogen in the presence of additional power in the form of a ‘‘bump’’ in the spectrum of cosmological density perturbations is calculated. The main absorption-amplifying effect is the earlier birth of the first stars forming an ultraviolet radiation background. This radiation reduces the spin temperature of neutral hydrogen and, thus, amplifies the absorption in the 21 cm line. A comparison of various cosmological models (with and without a bump in the density perturbation spectrum) shows that it is possible to determine the probable position of the bump in the perturbation spectrum and, thus, to reconstruct the spectrum of cosmological perturbations on scales \(k>1\) Mpc \({}^{-1}\) from the position of the absorption frequency profile.