arXiv subjects

Gabriel Pallares

Publications and source records attributed to Gabriel Pallares.

2 recordsLinked to original sources

arXiv2002

Fermion scattering off electroweak phase transition kink walls with hypermagnetic fields

We study the scattering of fermions off a finite width kink wall during the electroweak phase transition in the presence of a background hypermagnetic field. We derive and solve the Dirac equation for such fermions and compute the reflection and transmission coefficients for the case when the fermions move from the symmetric to the broken symmetry phase. We show that the chiral nature of the fermion coupling with the background field in the symmetric phase generates an axial asymmetry in the scattering processes. We discuss possible implications of such axial charge segregation for baryon number generation.

hep-ph↗

arXiv2000

Electroweak baryogenesis in the standard model with strong hypermagnetic fields

We show that in the presence of large scale primordial hypermagnetic fields, it is possible to generate a large amount of CP violation to explain the baryon to entropy ratio during the electroweak phase transition within the standard model. The mechanism responsible for the existence of a CP violating asymmetry is the chiral nature of the fermion coupling to the background field in the symmetric phase which can be used to construct two-fermion interference processes in analogy to the Bohm-Aharanov effect. We estimate that for strong hypermagnetic fields B_Y=(0.3-0.5)T^2 the baryon to entropy ratio can be rho_B/s=(3 - 6)X10^-11 for slowly expanding bubble walls.

hep-ph↗