高能暂现源 · 每日文献综述

A phase transition in the dark sector (DS) presents a promising explanation for the stochastic gravitational wave (GW) signals detected in recent observations by Pulsar Timing Arrays (PTAs). Instead of focusing solely on fitting data with phenomenological parameters, we systematically delineate simple, underlying DS models at the microscopic, Lagrangian level and uncover the conditions required to yield the GW spectrum observed by PTAs. Within this framework, the characteristic scale of the dark sector is <mml:math><mml:mi>O</mml:mi></mml:math>(MeV), with complementary tests at future energy- and intensity-frontier experiments.