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Title: NON-EXTENSIVE STATISTICS TO THE COSMOLOGICAL LITHIUM PROBLEM

Abstract

Big Bang nucleosynthesis (BBN) theory predicts the abundances of the light elements D, {sup 3}He, {sup 4}He, and {sup 7}Li produced in the early universe. The primordial abundances of D and {sup 4}He inferred from observational data are in good agreement with predictions, however, BBN theory overestimates the primordial {sup 7}Li abundance by about a factor of three. This is the so-called “cosmological lithium problem.” Solutions to this problem using conventional astrophysics and nuclear physics have not been successful over the past few decades, probably indicating the presence of new physics during the era of BBN. We have investigated the impact on BBN predictions of adopting a generalized distribution to describe the velocities of nucleons in the framework of Tsallis non-extensive statistics. This generalized velocity distribution is characterized by a parameter q , and reduces to the usually assumed Maxwell–Boltzmann distribution for q  = 1. We find excellent agreement between predicted and observed primordial abundances of D, {sup 4}He, and {sup 7}Li for 1.069 ≤  q  ≤ 1.082, suggesting a possible new solution to the cosmological lithium problem.

Authors:
;  [1];  [2];  [3];  [4];  [5];  [6];  [7]
  1. Key Laboratory of High Precision Nuclear Spectroscopy, Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China)
  2. Departament de Física i Enginyeria Nuclear, EUETIB, Universitat Politècnica de Catalunya, Barcelona E-08036 (Spain)
  3. Center for Nuclear Study, The University of Tokyo, RIKEN campus, Wako, Saitama 351-0198 (Japan)
  4. Texas A and M University-Commerce, Commerce, TX 75429-3011 (United States)
  5. Department of Astronomy, School of Science, the University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033 (Japan)
  6. National Astronomical Observatory of Japan 2-21-1 Osawa, Mitaka, Tokyo, 181-8588 (Japan)
  7. Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China)
Publication Date:
OSTI Identifier:
22661383
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 834; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ASTROPHYSICS; BOLTZMANN STATISTICS; COSMOLOGY; ELEMENT ABUNDANCE; HELIUM 3; HELIUM 4; LITHIUM 7; NUCLEONS; NUCLEOSYNTHESIS; PLASMA; STATISTICS; UNIVERSE; VELOCITY; VISIBLE RADIATION

Citation Formats

Hou, S. Q., He, J. J., Parikh, A., Kahl, D., Bertulani, C. A., Kajino, T., Mathews, G. J., and Zhao, G., E-mail: hejianjun@nao.cas.cn. NON-EXTENSIVE STATISTICS TO THE COSMOLOGICAL LITHIUM PROBLEM. United States: N. p., 2017. Web. doi:10.3847/1538-4357/834/2/165.
Hou, S. Q., He, J. J., Parikh, A., Kahl, D., Bertulani, C. A., Kajino, T., Mathews, G. J., & Zhao, G., E-mail: hejianjun@nao.cas.cn. NON-EXTENSIVE STATISTICS TO THE COSMOLOGICAL LITHIUM PROBLEM. United States. doi:10.3847/1538-4357/834/2/165.
Hou, S. Q., He, J. J., Parikh, A., Kahl, D., Bertulani, C. A., Kajino, T., Mathews, G. J., and Zhao, G., E-mail: hejianjun@nao.cas.cn. Tue . "NON-EXTENSIVE STATISTICS TO THE COSMOLOGICAL LITHIUM PROBLEM". United States. doi:10.3847/1538-4357/834/2/165.
@article{osti_22661383,
title = {NON-EXTENSIVE STATISTICS TO THE COSMOLOGICAL LITHIUM PROBLEM},
author = {Hou, S. Q. and He, J. J. and Parikh, A. and Kahl, D. and Bertulani, C. A. and Kajino, T. and Mathews, G. J. and Zhao, G., E-mail: hejianjun@nao.cas.cn},
abstractNote = {Big Bang nucleosynthesis (BBN) theory predicts the abundances of the light elements D, {sup 3}He, {sup 4}He, and {sup 7}Li produced in the early universe. The primordial abundances of D and {sup 4}He inferred from observational data are in good agreement with predictions, however, BBN theory overestimates the primordial {sup 7}Li abundance by about a factor of three. This is the so-called “cosmological lithium problem.” Solutions to this problem using conventional astrophysics and nuclear physics have not been successful over the past few decades, probably indicating the presence of new physics during the era of BBN. We have investigated the impact on BBN predictions of adopting a generalized distribution to describe the velocities of nucleons in the framework of Tsallis non-extensive statistics. This generalized velocity distribution is characterized by a parameter q , and reduces to the usually assumed Maxwell–Boltzmann distribution for q  = 1. We find excellent agreement between predicted and observed primordial abundances of D, {sup 4}He, and {sup 7}Li for 1.069 ≤  q  ≤ 1.082, suggesting a possible new solution to the cosmological lithium problem.},
doi = {10.3847/1538-4357/834/2/165},
journal = {Astrophysical Journal},
number = 2,
volume = 834,
place = {United States},
year = {Tue Jan 10 00:00:00 EST 2017},
month = {Tue Jan 10 00:00:00 EST 2017}
}
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