## Abstract

We study particle production at the collision of two domain walls in 5-dimensional Minkowski spacetime. This may provide the reheating mechanism of an ekpyrotic (or cyclic) brane universe, in which two BPS branes collide and evolve into a hot big bang universe. We evaluate a production rate of particles confined to the domain wall. The energy density of created particles is given as ρ ≈ 20g^{-4} N_{b}m_{n}^{4} where g is a coupling constant of particles to a domain-wall scalar field, N_{b} is the number of bounces at the collision and m_{n} is the fundamental mass scale of the domain wall. It does not depend on the width d of the domain wall, although the typical energy scale of created particles is given by ω ∼ 1/d. The reheating temperature is evaluated as T_{R} ≈ 0.88̄N_{b}^{1/4}. In order to have the baryogenesis at the electro-weak energy scale, the fundamental mass scale is constrained as m _{n} ≥ 1.1 × 10^{7} GeV for ̄ ∼ 10 ^{-5}.

Original language | English |
---|---|

Article number | 123514 |

Pages (from-to) | 123514-1-123514-12 |

Journal | Physical Review D - Particles, Fields, Gravitation and Cosmology |

Volume | 70 |

Issue number | 12 |

DOIs | |

Publication status | Published - 2004 Dec |

## ASJC Scopus subject areas

- Physics and Astronomy (miscellaneous)