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تسجيل مستخدم جديدMulti-period structure of electro-weak phase transition in the 3-3-1-1 model
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The electroweak phase transition (EWPT) is considered in the framework of 3-3-1-1 model for Dark Matter. The phase structure within three or two periods is approximated for the theory with many vacuum expectation values (VEVs) at TeV and Electroweak scales. In the mentioned model, there are two pictures. The first picture containing two periods of EWPT, has a transition $SU(3) rightarrow SU(2)$ at 6 TeV scale and another is $SU(2) rightarrow U(1)$ transition which is the like-standard model EWPT. The second picture is an EWPT structure containing three periods, in which two first periods are similar to those of the first picture and another one is the symmetry breaking process of $U(1)_N$ subgroup. Our study leads to the conclusion that EWPTs are the first order phase transitions when new bosons are triggers and their masses are within range of some TeVs. Especially, in two pictures, the maximum strength of the $SU(2) rightarrow U(1)$ phase transition is equal to 2.12 so this EWPT is not strong. Moreover, neutral fermions, which are candidates for Dark Matter and obey the Fermi-Dirac distribution, can be a negative trigger for EWPT. However, they do not make lose the first-order EWPT at TeV scale. Furthermore, in order to be the strong first-order EWPT at TeV scale, the symmetry breaking processes must produce more bosons than fermions or the mass of bosons must be much larger than that of fermions.
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