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Structure formation with massive neutrinos: going beyond linear theory
We compute non-linear corrections to the matter power spectrum taking the time- and scale-dependent free-streaming length of neutrinos into account. We adopt a hybrid scheme that matches the full Boltzmann hierarchy to an effective two-fluid description at an intermediate redshift. The non-lineariti...
Autores principales: | , , , |
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Lenguaje: | eng |
Publicado: |
2014
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Materias: | |
Acceso en línea: | https://dx.doi.org/10.1088/1475-7516/2014/11/039 http://cds.cern.ch/record/1750009 |
_version_ | 1780943102622564352 |
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author | Blas, Diego Garny, Mathias Konstandin, Thomas Lesgourgues, Julien |
author_facet | Blas, Diego Garny, Mathias Konstandin, Thomas Lesgourgues, Julien |
author_sort | Blas, Diego |
collection | CERN |
description | We compute non-linear corrections to the matter power spectrum taking the time- and scale-dependent free-streaming length of neutrinos into account. We adopt a hybrid scheme that matches the full Boltzmann hierarchy to an effective two-fluid description at an intermediate redshift. The non-linearities in the neutrino component are taken into account by using an extension of the time-flow framework. We point out that this remedies a spurious behaviour that occurs when neglecting non-linear terms for neutrinos. This behaviour is related to how efficiently short modes decouple from long modes and can be traced back to the violation of momentum conservation if neutrinos are treated linearly. Furthermore, we compare our results at next to leading order to various other methods and quantify the accuracy of the fluid description. Due to the correct decoupling behaviour of short modes, the two-fluid scheme is a suitable starting point to compute higher orders in perturbations or for resummation methods. |
id | cern-1750009 |
institution | Organización Europea para la Investigación Nuclear |
language | eng |
publishDate | 2014 |
record_format | invenio |
spelling | cern-17500092023-01-26T08:06:54Zdoi:10.1088/1475-7516/2014/11/039http://cds.cern.ch/record/1750009engBlas, DiegoGarny, MathiasKonstandin, ThomasLesgourgues, JulienStructure formation with massive neutrinos: going beyond linear theoryAstrophysics and AstronomyWe compute non-linear corrections to the matter power spectrum taking the time- and scale-dependent free-streaming length of neutrinos into account. We adopt a hybrid scheme that matches the full Boltzmann hierarchy to an effective two-fluid description at an intermediate redshift. The non-linearities in the neutrino component are taken into account by using an extension of the time-flow framework. We point out that this remedies a spurious behaviour that occurs when neglecting non-linear terms for neutrinos. This behaviour is related to how efficiently short modes decouple from long modes and can be traced back to the violation of momentum conservation if neutrinos are treated linearly. Furthermore, we compare our results at next to leading order to various other methods and quantify the accuracy of the fluid description. Due to the correct decoupling behaviour of short modes, the two-fluid scheme is a suitable starting point to compute higher orders in perturbations or for resummation methods.We compute non-linear corrections to the matter power spectrum taking the time- and scale-dependent free-streaming length of neutrinos into account. We adopt a hybrid scheme that matches the full Boltzmann hierarchy to an effective two-fluid description at an intermediate redshift. The non-linearities in the neutrino component are taken into account by using an extension of the time-flow framework. We point out that this remedies a spurious behaviour that occurs when neglecting non-linear terms for neutrinos. This behaviour is related to how efficiently short modes decouple from long modes and can be traced back to the violation of momentum conservation if neutrinos are treated linearly. Furthermore, we compare our results at next to leading order to various other methods and quantify the accuracy of the fluid description. Due to the correct decoupling behaviour of short modes, the two-fluid scheme is a suitable starting point to compute higher orders in perturbations or for resummation methods.We compute non-linear corrections to the matter power spectrum taking the time- and scale-dependent free-streaming length of neutrinos into account. We adopt a hybrid scheme that matches the full Boltzmann hierarchy to an effective two-fluid description at an intermediate redshift. The non-linearities in the neutrino component are taken into account by using an extension of the time-flow framework. We point out that this remedies a spurious behaviour that occurs when neglecting non-linear terms for neutrinos. This behaviour is related to how efficiently short modes decouple from long modes and can be traced back to the violation of momentum conservation if neutrinos are treated linearly. Furthermore, we compare our results at next to leading order to various other methods and quantify the accuracy of the fluid description. Due to the correct decoupling behaviour of short modes, the two-fluid scheme is a suitable starting point to compute higher orders in perturbations or for resummation methods.arXiv:1408.2995CERN-PH-TH-2014-149DESY-14-143CERN-PH-TH-2014-149DESY 14-143oai:cds.cern.ch:17500092014-08-13 |
spellingShingle | Astrophysics and Astronomy Blas, Diego Garny, Mathias Konstandin, Thomas Lesgourgues, Julien Structure formation with massive neutrinos: going beyond linear theory |
title | Structure formation with massive neutrinos: going beyond linear theory |
title_full | Structure formation with massive neutrinos: going beyond linear theory |
title_fullStr | Structure formation with massive neutrinos: going beyond linear theory |
title_full_unstemmed | Structure formation with massive neutrinos: going beyond linear theory |
title_short | Structure formation with massive neutrinos: going beyond linear theory |
title_sort | structure formation with massive neutrinos: going beyond linear theory |
topic | Astrophysics and Astronomy |
url | https://dx.doi.org/10.1088/1475-7516/2014/11/039 http://cds.cern.ch/record/1750009 |
work_keys_str_mv | AT blasdiego structureformationwithmassiveneutrinosgoingbeyondlineartheory AT garnymathias structureformationwithmassiveneutrinosgoingbeyondlineartheory AT konstandinthomas structureformationwithmassiveneutrinosgoingbeyondlineartheory AT lesgourguesjulien structureformationwithmassiveneutrinosgoingbeyondlineartheory |