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Title: Cosmological constraints in the presence of ionizing and resonance radiation at recombination

Abstract

With the recent measurement of full sky cosmic microwave background (CMB) polarization from WMAP, key cosmological degeneracies have been broken, allowing tighter constraints to be placed on cosmological parameters inferred assuming a standard recombination scenario. Here we consider the effect on cosmological constraints if additional ionizing and resonance radiation sources are present at recombination. We find that the new CMB data significantly improve the constraints on the additional radiation sources, with log{sub 10}[{epsilon}{sub {alpha}}]<-0.5 and log{sub 10}[{epsilon}{sub i}]<-2.4 at 95% c.l. for resonance and ionizing sources, respectively. Including the generalized recombination scenario, however, we find that the constraints on the scalar spectral index n{sub s} are weakened to n{sub s}=0.98{+-}0.03, with the n{sub s}=1 case now well inside the 95% c.l. The relaxation of constraints on tensor modes, scale invariance, dark energy and neutrino masses are also discussed.

Authors:
 [1];  [2];  [3]
  1. Dept. of Astronomy, Space Sciences Building, Cornell University, Ithaca, New York (United States)
  2. Dipartimento di Fisica e sezione INFN, Universita' di Roma 'La Sapienza', Ple Aldo Moro 2, 00185, Rome (Italy)
  3. Astrophysics, Denys Wilkinson Building, University of Oxford, Keble Road, OX3RH, Oxford (United Kingdom)
Publication Date:
OSTI Identifier:
21020129
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 6; Other Information: DOI: 10.1103/PhysRevD.75.063505; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; COSMIC NEUTRINOS; COSMOLOGY; NONLUMINOUS MATTER; POLARIZATION; RADIATION SOURCES; RECOMBINATION; RELAXATION; RELICT RADIATION; REST MASS; SCALE INVARIANCE; TENSORS

Citation Formats

Bean, Rachel, Melchiorri, Alessandro, and Silk, Joseph. Cosmological constraints in the presence of ionizing and resonance radiation at recombination. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.063505.
Bean, Rachel, Melchiorri, Alessandro, & Silk, Joseph. Cosmological constraints in the presence of ionizing and resonance radiation at recombination. United States. doi:10.1103/PHYSREVD.75.063505.
Bean, Rachel, Melchiorri, Alessandro, and Silk, Joseph. Thu . "Cosmological constraints in the presence of ionizing and resonance radiation at recombination". United States. doi:10.1103/PHYSREVD.75.063505.
@article{osti_21020129,
title = {Cosmological constraints in the presence of ionizing and resonance radiation at recombination},
author = {Bean, Rachel and Melchiorri, Alessandro and Silk, Joseph},
abstractNote = {With the recent measurement of full sky cosmic microwave background (CMB) polarization from WMAP, key cosmological degeneracies have been broken, allowing tighter constraints to be placed on cosmological parameters inferred assuming a standard recombination scenario. Here we consider the effect on cosmological constraints if additional ionizing and resonance radiation sources are present at recombination. We find that the new CMB data significantly improve the constraints on the additional radiation sources, with log{sub 10}[{epsilon}{sub {alpha}}]<-0.5 and log{sub 10}[{epsilon}{sub i}]<-2.4 at 95% c.l. for resonance and ionizing sources, respectively. Including the generalized recombination scenario, however, we find that the constraints on the scalar spectral index n{sub s} are weakened to n{sub s}=0.98{+-}0.03, with the n{sub s}=1 case now well inside the 95% c.l. The relaxation of constraints on tensor modes, scale invariance, dark energy and neutrino masses are also discussed.},
doi = {10.1103/PHYSREVD.75.063505},
journal = {Physical Review. D, Particles Fields},
number = 6,
volume = 75,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
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