Improved limits on short-wavelength gravitational waves from the cosmic microwave background
The cosmic microwave background (CMB) is affected by the total radiation density around the time of decoupling. At that epoch, neutrinos comprised a significant fraction of the radiative energy, but there could also be a contribution from primordial gravitational waves with frequencies greater than...
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ftdatacite:10.48550/arxiv.1203.4232 2023-05-15T18:23:06+02:00 Improved limits on short-wavelength gravitational waves from the cosmic microwave background Sendra, Irene Smith, Tristan L. 2012 https://dx.doi.org/10.48550/arxiv.1203.4232 https://arxiv.org/abs/1203.4232 unknown arXiv https://dx.doi.org/10.1103/physrevd.85.123002 arXiv.org perpetual, non-exclusive license http://arxiv.org/licenses/nonexclusive-distrib/1.0/ Cosmology and Nongalactic Astrophysics astro-ph.CO High Energy Physics - Phenomenology hep-ph High Energy Physics - Theory hep-th FOS Physical sciences article-journal Article ScholarlyArticle Text 2012 ftdatacite https://doi.org/10.48550/arxiv.1203.4232 https://doi.org/10.1103/physrevd.85.123002 2022-04-01T13:54:13Z The cosmic microwave background (CMB) is affected by the total radiation density around the time of decoupling. At that epoch, neutrinos comprised a significant fraction of the radiative energy, but there could also be a contribution from primordial gravitational waves with frequencies greater than ~ 10^-15 Hz. If this cosmological gravitational wave background (CGWB) were produced under adiabatic initial conditions, its effects on the CMB and matter power spectrum would mimic massless non-interacting neutrinos. However, with homogenous initial conditions, as one might expect from certain models of inflation, pre big-bang models, phase transitions and other scenarios, the effect on the CMB would be distinct. We present updated observational bounds for both initial conditions using the latest CMB data at small scales from the South Pole Telescope (SPT) in combination with Wilkinson Microwave Anisotropy Probe (WMAP), current measurements of the baryon acoustic oscillations, and the Hubble parameter. With the inclusion of the data from SPT the adiabatic bound on the CGWB density is improved by a factor of 1.7 to 10^6 Omega_gw < 8.7 at the 95% confidence level (C.L.), with weak evidence in favor of an additional radiation component consistent with previous analyses. The constraint can be converted into an upper limit on the tension of horizon-sized cosmic strings that could generate this gravitational wave component, with Gmu < 2 10^-7 at 95% C.L., for string tension Gmu. The homogeneous bound improves by a factor of 3.5 to 10^6 Omega_gw < 1.0 at 95% C.L., with no evidence for such a component from current data. : 5 pages, 3 figures Text South pole DataCite Metadata Store (German National Library of Science and Technology) Hubble ENVELOPE(158.317,158.317,-80.867,-80.867) South Pole Wilkinson ENVELOPE(-66.200,-66.200,-66.817,-66.817) |
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DataCite Metadata Store (German National Library of Science and Technology) |
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ftdatacite |
language |
unknown |
topic |
Cosmology and Nongalactic Astrophysics astro-ph.CO High Energy Physics - Phenomenology hep-ph High Energy Physics - Theory hep-th FOS Physical sciences |
spellingShingle |
Cosmology and Nongalactic Astrophysics astro-ph.CO High Energy Physics - Phenomenology hep-ph High Energy Physics - Theory hep-th FOS Physical sciences Sendra, Irene Smith, Tristan L. Improved limits on short-wavelength gravitational waves from the cosmic microwave background |
topic_facet |
Cosmology and Nongalactic Astrophysics astro-ph.CO High Energy Physics - Phenomenology hep-ph High Energy Physics - Theory hep-th FOS Physical sciences |
description |
The cosmic microwave background (CMB) is affected by the total radiation density around the time of decoupling. At that epoch, neutrinos comprised a significant fraction of the radiative energy, but there could also be a contribution from primordial gravitational waves with frequencies greater than ~ 10^-15 Hz. If this cosmological gravitational wave background (CGWB) were produced under adiabatic initial conditions, its effects on the CMB and matter power spectrum would mimic massless non-interacting neutrinos. However, with homogenous initial conditions, as one might expect from certain models of inflation, pre big-bang models, phase transitions and other scenarios, the effect on the CMB would be distinct. We present updated observational bounds for both initial conditions using the latest CMB data at small scales from the South Pole Telescope (SPT) in combination with Wilkinson Microwave Anisotropy Probe (WMAP), current measurements of the baryon acoustic oscillations, and the Hubble parameter. With the inclusion of the data from SPT the adiabatic bound on the CGWB density is improved by a factor of 1.7 to 10^6 Omega_gw < 8.7 at the 95% confidence level (C.L.), with weak evidence in favor of an additional radiation component consistent with previous analyses. The constraint can be converted into an upper limit on the tension of horizon-sized cosmic strings that could generate this gravitational wave component, with Gmu < 2 10^-7 at 95% C.L., for string tension Gmu. The homogeneous bound improves by a factor of 3.5 to 10^6 Omega_gw < 1.0 at 95% C.L., with no evidence for such a component from current data. : 5 pages, 3 figures |
format |
Text |
author |
Sendra, Irene Smith, Tristan L. |
author_facet |
Sendra, Irene Smith, Tristan L. |
author_sort |
Sendra, Irene |
title |
Improved limits on short-wavelength gravitational waves from the cosmic microwave background |
title_short |
Improved limits on short-wavelength gravitational waves from the cosmic microwave background |
title_full |
Improved limits on short-wavelength gravitational waves from the cosmic microwave background |
title_fullStr |
Improved limits on short-wavelength gravitational waves from the cosmic microwave background |
title_full_unstemmed |
Improved limits on short-wavelength gravitational waves from the cosmic microwave background |
title_sort |
improved limits on short-wavelength gravitational waves from the cosmic microwave background |
publisher |
arXiv |
publishDate |
2012 |
url |
https://dx.doi.org/10.48550/arxiv.1203.4232 https://arxiv.org/abs/1203.4232 |
long_lat |
ENVELOPE(158.317,158.317,-80.867,-80.867) ENVELOPE(-66.200,-66.200,-66.817,-66.817) |
geographic |
Hubble South Pole Wilkinson |
geographic_facet |
Hubble South Pole Wilkinson |
genre |
South pole |
genre_facet |
South pole |
op_relation |
https://dx.doi.org/10.1103/physrevd.85.123002 |
op_rights |
arXiv.org perpetual, non-exclusive license http://arxiv.org/licenses/nonexclusive-distrib/1.0/ |
op_doi |
https://doi.org/10.48550/arxiv.1203.4232 https://doi.org/10.1103/physrevd.85.123002 |
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1766202541704478720 |