3 papers
hep-ph2026
Particle Production via Rippled Bubble Walls
Ryusuke Jinno, Shota Nakagawa, Yuichiro Nakai +1
We investigate non-thermal particle production during first-order phase transitions in the presence of ultra-relativistic thick bubble walls with non-trivial internal structure. Ex…
hep-ph2025
Exploring the Landscape of Spontaneous CP Violation in Supersymmetric Theories
Fangchao Liu, Shota Nakagawa, Yuichiro Nakai +1
The strong CP problem remains one of the most important unresolved issues in the Standard Model. Spontaneous CP violation (SCPV) is a promising approach to the problem by assuming…
hep-ph2025
High Reheating Temperature without Axion Domain Walls
Shota Nakagawa, Yuichiro Nakai, Yu-Cheng Qiu +2
We investigate a cosmological scenario in which the Peccei-Quinn (PQ) symmetry remains broken in the entire history of the Universe, thereby avoiding the formation of axion strings…