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Title: Challenges and prospects for better measurements of the CMB intensity spectrum

Abstract

Spectral distortions of the Cosmic Microwave Background (CMB) offer the possibility of probing processes which occurred during the evolution of our Universe going back up to Z≅ 10{sup 7}. Unfortunately all the attempts so far carried out for detecting distortions failed. All of them were based on comparisons among absolute measurements of the CMB temperature at different frequencies. We suggest a different approach: measurements of the frequency derivative of the CMB temperature over large frequency intervals instead of observations of the absolute temperature at few, well separated, frequencies as frequently done in the past, and, direct measurements of the foregrounds which hinder observations, at the same site and with the same radiometer prepared for the search of CMB distortions. We discuss therefore the perspectives of new observations in the next years from the ground, at very special sites, or in space as independent missions or part of other CMB projects.

Authors:
 [1]
  1. Physics Department, University of Milano Bicocca, Piazza della Scienza 3, Milano (Italy)
Publication Date:
OSTI Identifier:
22680034
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2017; Journal Issue: 02; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; COMPARATIVE EVALUATIONS; EVOLUTION; RELICT RADIATION; SPACE; SPECTRA; UNIVERSE

Citation Formats

Sironi, Giorgio, E-mail: giorgio.sironi@unimb.it. Challenges and prospects for better measurements of the CMB intensity spectrum. United States: N. p., 2017. Web. doi:10.1088/1475-7516/2017/02/023.
Sironi, Giorgio, E-mail: giorgio.sironi@unimb.it. Challenges and prospects for better measurements of the CMB intensity spectrum. United States. doi:10.1088/1475-7516/2017/02/023.
Sironi, Giorgio, E-mail: giorgio.sironi@unimb.it. Wed . "Challenges and prospects for better measurements of the CMB intensity spectrum". United States. doi:10.1088/1475-7516/2017/02/023.
@article{osti_22680034,
title = {Challenges and prospects for better measurements of the CMB intensity spectrum},
author = {Sironi, Giorgio, E-mail: giorgio.sironi@unimb.it},
abstractNote = {Spectral distortions of the Cosmic Microwave Background (CMB) offer the possibility of probing processes which occurred during the evolution of our Universe going back up to Z≅ 10{sup 7}. Unfortunately all the attempts so far carried out for detecting distortions failed. All of them were based on comparisons among absolute measurements of the CMB temperature at different frequencies. We suggest a different approach: measurements of the frequency derivative of the CMB temperature over large frequency intervals instead of observations of the absolute temperature at few, well separated, frequencies as frequently done in the past, and, direct measurements of the foregrounds which hinder observations, at the same site and with the same radiometer prepared for the search of CMB distortions. We discuss therefore the perspectives of new observations in the next years from the ground, at very special sites, or in space as independent missions or part of other CMB projects.},
doi = {10.1088/1475-7516/2017/02/023},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 02,
volume = 2017,
place = {United States},
year = {Wed Feb 01 00:00:00 EST 2017},
month = {Wed Feb 01 00:00:00 EST 2017}
}
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