Standard model CP violation and baryon asymmetry

Dec, 1993
15 pages
Published in:
  • Mod.Phys.Lett.A 9 (1994) 795-810
e-Print:
Report number:
  • CERN-TH-7081-93,
  • LPTHE-ORSAY-93-48,
  • HUTP-93-A036,
  • HD-THEP-93-45

Citations per year

19942002201020182025010203040
Abstract: (arXiv)
Simply based on CP arguments, we argue against a Standard Model explanation of the baryon asymmetry of the universe in the presence of a first order phase transition. A CP-asymmetry is found in the reflection coefficients of quarks hitting the phase boundary created during the electroweak transition. The problem is analyzed both in an academic zero temperature case and in the realistic finite temperature one. The building blocks are similar in both cases: Kobayashi-Maskawa CP-violation, CP-even phases in the reflection coefficients of quarks, and physical transitions due to fermion self-energies. In both cases an effect is present at order αW2\alpha_W^2 in rate. A standard GIM behaviour is found as intuitively expected. In the finite temperature case, a crucial role is played by the damping rate of quasi-particles in a hot plasma, which is a relevant scale together with MWM_W and the temperature. The effect is many orders of magnitude below what observation requires, and indicates that non standard physics is indeed needed in the cosmological scenario.
Note:
  • 15p, LaTeX (3figs incl.), CERN 93/7081,LPTHE Orsay-93/48,HUTP-93/A036,HD-THEP-93-45
  • CP: violation
  • baryon: asymmetry
  • critical phenomena
  • finite temperature
  • CKM matrix matrix
  • Glashow-Iliopoulos-Maiani model
  • plasma: energy loss
  • gauge field theory: SU(3) x SU(2) x U(1)