Gravitational waves from phase transition in minimal SUSY U(1)B−L model

• DOI: 10.1103/physrevd.101.075027
• Publication Date: 2020-04-16T12:23:36Z
• Authors: Naoyuki Haba; Toshifumi Yamada
• Keywords: High Energy Physics - Phenomenology; High Energy Physics - Phenomenology (hep-ph); 0103 physical sciences; FOS: Physical sciences; 01 natural sciences

Many extensions of the Standard Model include a new $U(1)$ gauge group that is broken spontaneously at a scale much above TeV. If a $U(1)$-breaking phase transition occurs at nucleation temperature of $O(100)$-$O(1000)$~TeV, it can generate stochastic gravitational waves in $O(10)$-$O(100)$ Hz range if $��_{\rm n}/H_{\rm n}=1000$, which can be detected by ground-based detectors. Meanwhile, supersymmetry (SUSY) may play a crucial role in the dynamics of such high-scale $U(1)$ gauge symmetry breaking, because SUSY breaking scale is expected to be at TeV to solve the hierarchy problem. In this paper, we study the phase transition of $U(1)$ gauge symmetry breaking in a SUSY model in the SUSY limit. We consider a particular example, the minimal SUSY $U(1)_{B-L}$ model. We derive the finite temperature effective potential of the model in the SUSY limit, study a $U(1)_{B-L}$-breaking phase transition, and estimate gravitational waves generated from it.<br/>26 pages, 10 figures. Sensitivity curves of Advanced LIGO design, Cosmic Explorer and Einstein Telescope are overlaid on the plots of predicted gravitational wave spectrum. We have shown that the percolation of true-vacuum bubbles is completed in the benchmark with large supercooling where alpha_\theta(T_n)=1.5. References are added. Version accepted for publication in Physical Review D<br/>