Thermal effects and sudden decay approximation in the curvaton scenario

Kitajima, Naoya; Takesako, Tomohiro; Yokoyama, Shuichiro; Langlois, David; Takahashi, Tomo

doi:10.1088/1475-7516/2014/10/032

Title: Thermal effects and sudden decay approximation in the curvaton scenario

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Abstract

We study the impact of a temperature-dependent curvaton decay rate on the primordial curvature perturbation generated in the curvaton scenario. Using the familiar sudden decay approximation, we obtain an analytical expression for the curvature perturbation after the decay of the curvaton. We then investigate numerically the evolution of the background and of the perturbations during the decay. We first show that the instantaneous transfer coefficient, related to the curvaton energy fraction at the decay, can be extended into a more general parameter, which depends on the net transfer of the curvaton energy into radiation energy or, equivalently, on the total entropy ratio after the complete curvaton decay. We then compute the curvature perturbation and compare this result with the sudden decay approximation prediction.

Authors:

Kitajima, Naoya; Takesako, Tomohiro; Yokoyama, Shuichiro ^[1]; Langlois, David ^[2]; Takahashi, Tomo ^[3]

Institute for Cosmic Ray Research, University of Tokyo, Kashiwa 277-8582 (Japan)
Astroparticle and Cosmologie (CNRS-Université Paris 7), 10 rue Alice Domon et Léonie Duquet, 75205 Paris Cedex 13 (France)
Department of Physics, Saga University, Saga 840-8502 (Japan)

Publication Date:: Wed Oct 01 00:00:00 EDT 2014

OSTI Identifier:: 22375830

Resource Type:: Journal Article

Journal Name:: Journal of Cosmology and Astroparticle Physics

Additional Journal Information:: Journal Volume: 2014; Journal Issue: 10; Other Information: Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 1475-7516

Country of Publication:: United States

Language:: English

Subject:: 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; APPROXIMATIONS; COMPARATIVE EVALUATIONS; DECAY; ENTROPY; EVOLUTION; FORECASTING; PERTURBATION THEORY; TEMPERATURE DEPENDENCE

Citation Formats


                    Kitajima, Naoya, Takesako, Tomohiro, Yokoyama, Shuichiro, Langlois, David, and Takahashi, Tomo. Thermal effects and sudden decay approximation in the curvaton scenario.  United States: N. p., 2014. 
        Web.  doi:10.1088/1475-7516/2014/10/032.

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                    Kitajima, Naoya, Takesako, Tomohiro, Yokoyama, Shuichiro, Langlois, David, & Takahashi, Tomo. Thermal effects and sudden decay approximation in the curvaton scenario.  United States.  https://doi.org/10.1088/1475-7516/2014/10/032

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                    Kitajima, Naoya, Takesako, Tomohiro, Yokoyama, Shuichiro, Langlois, David, and Takahashi, Tomo. 2014.  
        "Thermal effects and sudden decay approximation in the curvaton scenario".  United States.  https://doi.org/10.1088/1475-7516/2014/10/032.

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@article{osti_22375830,

  title        = {Thermal effects and sudden decay approximation in the curvaton scenario},

  author       = {Kitajima, Naoya and Takesako, Tomohiro and Yokoyama, Shuichiro and Langlois, David and Takahashi, Tomo},

  abstractNote = {We study the impact of a temperature-dependent curvaton decay rate on the primordial curvature perturbation generated in the curvaton scenario. Using the familiar sudden decay approximation, we obtain an analytical expression for the curvature perturbation after the decay of the curvaton. We then investigate numerically the evolution of the background and of the perturbations during the decay. We first show that the instantaneous transfer coefficient, related to the curvaton energy fraction at the decay, can be extended into a more general parameter, which depends on the net transfer of the curvaton energy into radiation energy or, equivalently, on the total entropy ratio after the complete curvaton decay. We then compute the curvature perturbation and compare this result with the sudden decay approximation prediction.},

  doi          = {10.1088/1475-7516/2014/10/032},

  url          = {https://www.osti.gov/biblio/22375830},
  journal      = {Journal of Cosmology and Astroparticle Physics},

  issn         = {1475-7516},

  number       = 10,

  volume       = 2014,

  place        = {United States},

  year         = {Wed Oct 01 00:00:00 EDT 2014},

  month        = {Wed Oct 01 00:00:00 EDT 2014}

}

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https://doi.org/10.1088/1475-7516/2014/10/032

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