Mirror QCD phase transition as the origin of the nanohertz Stochastic Gravitational-Wave Background

Jun 29, 2023
7 pages
Published in:
  • Sci.Bull. 69 (2024) 741-746
  • Published: Jan 30, 2024
e-Print:
DOI:

Citations per year

20222023202404217
Abstract: (Elsevier B.V.)
Several Pulsar Timing Array (PTA) Collaborations have recently provided strong evidence for a nHz Stochastic Gravitational-Wave Background (SGWB). Here we investigate the implications of a first-order phase transition occurring within the early Universe’s dark quantum chromodynamics epoch, specifically within the framework of the mirror twin Higgs dark sector model. Our analysis indicates a distinguishable SGWB signal originating from this phase transition, which can explain the measurements obtained by PTAs. Remarkably, a significant portion of the parameter space for the SGWB signal also effectively resolves the existing tensions in both the H0 and S8 measurements in Cosmology. This intriguing correlation suggests a possible common origin of these three phenomena for 0.2<ΔNeff<0.5, where the mirror dark matter component constitutes less than 30% of the total dark matter abundance. Next-generation CMB experiments such as CMB-S4 can test this parameter region.
Note:
  • 7 pages, 4 figures
  • Mirror twin Higgs
  • Dark matter
  • Phase transition
  • Gravitational wave
  • Pulsar timing array
  • gravitational radiation: background
  • gravitational radiation: stochastic
  • dark matter: mirror
  • quantum chromodynamics: critical phenomena
  • pulsar