Constraint on $B-L$ cosmic string from leptogenesis with degenerate neutrinos

Abstract

In the early Universe, as a consequence of $U(1{)}_{B-L}$ gauge symmetry-breaking, the so-called $B-L$ cosmic strings are expected to be produced at the breaking scale ${\eta }_{B-L}$ according to the Kibble mechanism. The decaying, collapsing closed loops of these strings can release the right-handed neutrinos, whose subsequent decay can contribute to the baryon asymmetry of the Universe (BAU), through the "slow death"(SD) process and/or the "quick death"(QD) process. In this paper, we assume that the decay of the lightest heavy Majorana neutrinos released from the $B-L$ cosmic string loops can produce a baryon asymmetry consistent with the cosmic microwave background (CMB) observations. Considering the fact that both the neutrinoless double beta decay experiment and the cosmological data show a preference for degenerate neutrinos, we give the lower limits for the breaking scale ${\eta }_{B-L}$ with the neutrino masses $0.06eV\le \bar{m}=(m_1^2+m_2^2+m_3^2{)}^{1/2}\le 1.0eV$, where the full possible cases of degenerate neutrinos are included. We obtain ${\eta }_{B-L}\gtrsim 3.3\times 10^{15}GeV$, $5.3\times 10^{15}GeV$ and $9.5\times 10^{15}GeV$ for $\bar{m}=0.2eV$, $0.4eV$ and $1.0eV$ respectively in the SD process, and find the $B-L$ cosmic string has a very small contribution to the BAU in the QD process.

arXiv comment12 pages, 3 figures; revised version, accepted for publication in Phys. Lett. B

References in corpus (20)

• First Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Determination of Cosmological Parameters
• Cosmological parameters from SDSS and WMAP
• First Results from KamLAND: Evidence for Reactor Anti-Neutrino Disappearance
• Cosmic strings
• A lower bound on the right-handed neutrino mass from leptogenesis
• Indications of Neutrino Oscillation in a 250 km Long-baseline Experiment
• Measurement of the Total Active 8B Solar Neutrino Flux at the Sudbury Neutrino Observatory with Enhanced Neutral Current Sensitivity
• EGRET Observations of the Extragalactic Gamma Ray Emission
• Origin and Propagation of Extremely High Energy Cosmic Rays
• Search for neutrinoless double beta decay with enriched 76Ge in Gran Sasso 1990-2003
• Cosmic Microwave Background, Matter-Antimatter Asymmetry and Neutrino Masses
• The Neutrino Mass Window for Baryogenesis
• Numerical simulations of string networks in the Abelian-Higgs model
• Baryogenesis via lepton number violation in Anti-GUT model
• Large Angle CMB Fluctuations from Cosmic Strings with a Comological Constant
• New mechanism for leptogenesis
• Cosmic Topological Defects, Highest Energy Cosmic Rays, and the Baryon Asymmetry of the Universe
• High Harmonic Configurations of Cosmic Strings: An Analysis of Self-Intersections
• B-L Cosmic strings and Baryogenesis
• Baryogenesis through Collapsing String Loops in Gauged Baryon and Lepton Models

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