CMB recombination lines of hydrogen: The differential spectrum

Astronomy Letters - Tập 30 - Trang 657-662 - 2004
V. K. Dubrovich1,2, S. I. Grachev3
1Special Astrophysical Observatory, St. Petersburg Branch, Russian Academy of Sciences, St. Petersburg, Russia
2Pulkovo Astronomical Observatory, Russian Academy of Sciences, St. Petersburg, Russia
3Sobolev Astronomical Institute, St. Petersburg State University, St. Petersburg, Russia

Tóm tắt

We have calculated the distortions of the cosmic microwave background (CMB) spectrum in the wavelength range 2–50 cm due to the superposition of the CMB hydrogen recombination radiation in subordinate lines. The level populations were determined by numerically solving the equation of recombination kinetics together with the statistical equilibrium equations for a 60-level model hydrogen atom. The relative distortions are ≈10−7–10−6, with their wavelength dependence having a low-contrast, wavy pattern. However, the contrast increases severalfold and becomes pronounced when passing to the differential distortion spectrum. We study the dependence of the distortions on cosmological parameters.

Tài liệu tham khảo

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