English

Revisiting Big-Bang Nucleosynthesis Constraints on Long-Lived Decaying Particles

High Energy Physics - Phenomenology 2018-12-04 v3 Cosmology and Nongalactic Astrophysics

Abstract

We study effects of long-lived massive particles, which decay during the big-bang nucleosynthesis (BBN) epoch, on the primordial abundances of light elements. Compared to the previous studies, (i) the reaction rates of the standard BBN reactions are updated, (ii) the most recent observational data of light element abundances and cosmological parameters are used, (iii) the effects of the interconversion of energetic nucleons at the time of inelastic scatterings with background nuclei are considered, and (iv) the effects of the hadronic shower induced by energetic high energy anti-nucleons are included. We compare the theoretical predictions on the primordial abundances of light elements with latest observational constraints, and derive upper bounds on relic abundance of the decaying particle as a function of its lifetime. We also apply our analysis to unstable gravitino, the superpartner of the graviton in supersymmetric theories, and obtain constraints on the reheating temperature after inflation.

Keywords

Cite

@article{arxiv.1709.01211,
  title  = {Revisiting Big-Bang Nucleosynthesis Constraints on Long-Lived Decaying Particles},
  author = {Masahiro Kawasaki and Kazunori Kohri and Takeo Moroi and Yoshitaro Takaesu},
  journal= {arXiv preprint arXiv:1709.01211},
  year   = {2018}
}

Comments

36 pages, 15 figures. Inaccuracy in the numerical calculation of photodissociation rates is corrected. Main conclusions are unchanged