Two Higgs doublet dynamics at the electroweak phase transition: a nonperturbative study
Abstract
Using a threedimensional (3d) effective field theory and nonperturbative lattice simulations, we study the MSSM electroweak phase transition with two dynamical Higgs doublets. We first carry out a general analysis of spontaneous CP violation in 3d two Higgs doublet models, finding that this part of the parameter space is well separated from that corresponding to the physical MSSM. We then choose physical parameter values with explicit CP violation and a light righthanded stop, and determine the strength of the phase transition. We find a transition somewhat stronger than in 2loop perturbation theory, leading to the conclusion that from the point of view of the nonequilibrium constraint, MSSM electroweak baryogenesis can be allowed even for a Higgs mass m _{H}≈115 GeV. We also find that small values of the mass parameter m _{A} ( ≲120 GeV), which would relax the experimental constraint on m _{H}, do not weaken the transition noticeably for a light enough stop. Finally we determine the properties of the phase boundary.
 Publication:

Nuclear Physics B
 Pub Date:
 March 2001
 DOI:
 10.1016/S05503213(00)007367
 arXiv:
 arXiv:heplat/0009025
 Bibcode:
 2001NuPhB.597...23L
 Keywords:

 High Energy Physics  Lattice;
 High Energy Physics  Phenomenology
 EPrint:
 56 pages, 16 figures