DW-genesis: baryon number from domain wall network collapse

Abstract Axionic domain walls, as they move through the early universe plasma during their collapse, can generate a net baryon and lepton number through the mechanism of spontaneous baryogenesis, provided that there is a coupling between the axion and the lepton or baryon current. In this paper, we...

Full description

Saved in:
Bibliographic Details
Main Authors: Alberto Mariotti, Xander Nagels, Aäron Rase, Miguel Vanvlasselaer
Format: Article
Language:English
Published: SpringerOpen 2025-03-01
Series:Journal of High Energy Physics
Subjects:
Online Access:https://doi.org/10.1007/JHEP03(2025)199
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Abstract Axionic domain walls, as they move through the early universe plasma during their collapse, can generate a net baryon and lepton number through the mechanism of spontaneous baryogenesis, provided that there is a coupling between the axion and the lepton or baryon current. In this paper, we study systematically the baryon asymmetry produced by these domain walls (DWs) at annihilation, within different realisations of the L- or B-violating sector, and refer to this process as DW-genesis. We find that the baryon number is maximised when the DW network collapses approximately at the moment when the L- or B-violating interaction decouples. We study a model of minimal leptogenesis, a model of cogenesis, a model of baryogenesis and finally the possibility that the baryon asymmetry is produced by electroweak sphalerons. As phenomenological consequences of DW-genesis, we discuss the expected gravitational wave signal from the DW network annihilation and the prospects for detecting it. However, we finally emphasize that in realisations of the DW-genesis in minimal post-inflationary scenarios, there is a suppression induced by the cancellation between the asymmetry created by “opposite” axionic domain walls attached to the string. We quantify the impact of this cancellation and discuss possible ways to avoid it.
ISSN:1029-8479