Non-Gaussianity in the Cosmic Microwave Background temperature fluctuations from cosmic (super-)strings

Takahashi, Keitaro; Naruko, Atsushi; Sendouda, Yuuiti; Yamauchi, Daisuke; Sasaki, Misao; Yoo, Chul-Moon

doi:10.1088/1475-7516/2009/10/003

Title: Non-Gaussianity in the Cosmic Microwave Background temperature fluctuations from cosmic (super-)strings

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Abstract

We compute analytically the small-scale temperature fluctuations of the cosmic microwave background from cosmic (super-)strings and study the dependence on the string intercommuting probability P. We develop an analytical model which describes the evolution of a string network and calculate the numbers of string segments and kinks in a horizon volume. Then we derive the probability distribution function (pdf) which takes account of finite angular resolution of observation. The resultant pdf consists of a Gaussian part due to frequent scatterings by long string segments and a non-Gaussian tail due to close encounters with kinks. The dispersion of the Gaussian part is reasonably consistent with that obtained by numerical simulations by Fraisse et al.. On the other hand, the non-Gaussian tail contains two phenomenological parameters which are determined by comparison with the numerical results for P = 1. Extrapolating the pdf to the cases with P < 1, we predict that the non-Gaussian feature is suppressed for small P.

Authors:

Takahashi, Keitaro ^[1]; Naruko, Atsushi; Sendouda, Yuuiti; Yamauchi, Daisuke; Sasaki, Misao ^[2]; Yoo, Chul-Moon ^[3]

Department of Physics and Astrophysics, Nagoya University, Furo-cho, Nagoya 464-8602 (Japan)
Yukawa Institute for Theoretical Physics, Kyoto University, Kitashirakawa Oiwake-cho, Sakyo-ku, Kyoto 606-8502 (Japan)
Asia Pacific Center for Theoretical Physics, Pohang University of Science and Technology, San 31, HYOJA-DONG, NAM-GU, Pohang 790-784 (Korea, Republic of)

Publication Date:: Thu Oct 01 00:00:00 EDT 2009

OSTI Identifier:: 22273054

Resource Type:: Journal Article

Journal Name:: Journal of Cosmology and Astroparticle Physics

Additional Journal Information:: Journal Volume: 2009; 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; ASTROPHYSICS; COMPARATIVE EVALUATIONS; COMPUTERIZED SIMULATION; DISTRIBUTION FUNCTIONS; FLUCTUATIONS; PROBABILITY; RELICT RADIATION; RESOLUTION; SCATTERING; STRING MODELS

Citation Formats


                    Takahashi, Keitaro, Naruko, Atsushi, Sendouda, Yuuiti, Yamauchi, Daisuke, Sasaki, Misao, and Yoo, Chul-Moon. Non-Gaussianity in the Cosmic Microwave Background temperature fluctuations from cosmic (super-)strings.  United States: N. p., 2009. 
        Web.  doi:10.1088/1475-7516/2009/10/003.

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                    Takahashi, Keitaro, Naruko, Atsushi, Sendouda, Yuuiti, Yamauchi, Daisuke, Sasaki, Misao, & Yoo, Chul-Moon. Non-Gaussianity in the Cosmic Microwave Background temperature fluctuations from cosmic (super-)strings.  United States.  https://doi.org/10.1088/1475-7516/2009/10/003

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                    Takahashi, Keitaro, Naruko, Atsushi, Sendouda, Yuuiti, Yamauchi, Daisuke, Sasaki, Misao, and Yoo, Chul-Moon. 2009.  
        "Non-Gaussianity in the Cosmic Microwave Background temperature fluctuations from cosmic (super-)strings".  United States.  https://doi.org/10.1088/1475-7516/2009/10/003.

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@article{osti_22273054,

  title        = {Non-Gaussianity in the Cosmic Microwave Background temperature fluctuations from cosmic (super-)strings},

  author       = {Takahashi, Keitaro and Naruko, Atsushi and Sendouda, Yuuiti and Yamauchi, Daisuke and Sasaki, Misao and Yoo, Chul-Moon},

  abstractNote = {We compute analytically the small-scale temperature fluctuations of the cosmic microwave background from cosmic (super-)strings and study the dependence on the string intercommuting probability P. We develop an analytical model which describes the evolution of a string network and calculate the numbers of string segments and kinks in a horizon volume. Then we derive the probability distribution function (pdf) which takes account of finite angular resolution of observation. The resultant pdf consists of a Gaussian part due to frequent scatterings by long string segments and a non-Gaussian tail due to close encounters with kinks. The dispersion of the Gaussian part is reasonably consistent with that obtained by numerical simulations by Fraisse et al.. On the other hand, the non-Gaussian tail contains two phenomenological parameters which are determined by comparison with the numerical results for P = 1. Extrapolating the pdf to the cases with P < 1, we predict that the non-Gaussian feature is suppressed for small P.},

  doi          = {10.1088/1475-7516/2009/10/003},

  url          = {https://www.osti.gov/biblio/22273054},
  journal      = {Journal of Cosmology and Astroparticle Physics},

  issn         = {1475-7516},

  number       = 10,

  volume       = 2009,

  place        = {United States},

  year         = {Thu Oct 01 00:00:00 EDT 2009},

  month        = {Thu Oct 01 00:00:00 EDT 2009}

}

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