2025/04/10 by Yu, Yan-Heng, Wang, Sai · 4 citations
#Cosmology and Nongalactic Astrophysics (astro-ph.CO) #FOS: Physical sciences #General Relativity and Quantum Cosmology (gr-qc) #High Energy Physics - Phenomenology (hep-ph)
paper · doi:10.48550/arxiv.2504.07838
Affleck-Dine (AD) baryogenesis can produce the baryon asymmetry of the Universe through the CP-violating dynamics of AD field. The field generally fragments into Q-balls, whose rapid decay induces enhanced gravitational waves. In this Letter, we investigate the anisotropies in this gravitational wave background as a new essential observable for AD baryogenesis. The evolution of AD field causes non-Gaussian baryonic isocurvature perturbations, and the non-Gaussianity modulates the spatial distribution of Q-balls on large scales, resulting in large-scale anisotropies in the Q-ball-induced gravitational wave background. We present that the anisotropies can be significantly large with a reduced angular power spectrum ∼ 10-2, and can be detected by future experiments like LISA. Moreover, these anisotropies universally reveal the CP-violating dynamics of AD field, opening a novel road to explore the longstanding baryon asymmetry puzzle.