Open AccessThe measurements of the CMB temperature in diffuse interstellar medium of the Milky-Way and high redshift galaxies based on excitation of CI fine-structure and H2 rotational levels
Author(s) -
В. В. Клименко,
A. V. Ivanchik
Publication year - 2020
Publication title -
journal of physics. conference series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 85
eISSN - 1742-6596
pISSN - 1742-6588
DOI - 10.1088/1742-6596/1697/1/012013
Subject(s) - cosmic microwave background , physics , redshift , galaxy , astrophysics , optics , anisotropy
Evolution of the cosmic microwave background (CMB) temperature with redshift T CMB = T CMB 0 × ( 1 + z ) is predicted by the standard ΛCDM cosmological model and has been confirmed by measurements of the Sunyaev-Zel’dovich effect in Plank data (at z ≤ 1) and excitation of CO rotational levels in quasar spectra (at 1.7 ≤ z ≤ 2.7). Excitation of the fine-structure levels of neutral carbon (C I ) is also sensitive to the temperature of the CMB radiation. However collisions and UV pumping lead to a significant degeneracy of the fitting parameters, since poor data on physical conditions. We found that a joint fit to excitation of low H 2 rotational and CI fine-structure levels can break this degeneracy and provide a tighter constraints on the T CMB . We present estimates of the T CMB derived from excitation of C I fine-structure levels in the Milky Way clouds and high redshift absorption systems.