TwoLoop Analysis of Gauge Couplig Unification with Anomalous U(1) Symmetry and Proton Decay
Abstract
Recently, a new mechanism, which explains why the three gauge coupling constants meet at a certain scale in the minimal supersymmetric standard model, has been proposed in a scenario of grand unified theories with anomalous U(1)_{A} gauge symmetry. It is a nontrivial result that although there are many superheavy fields whose mass scales are below the unification scale, this mechanism explains this fact by means of oneloop renormalization group equations. Since the unification scale generically becomes below the usual GUT scale, 2 × 10^{16} GeV, and proton decay via dimension 5 operators is suppressed, the scenario predicts that proton decay via dimension 6 operators, p rightarrow e π^{0}, will be observed in the near future. In this paper, we attempt to estimate a reasonable range of values of the lifetime of the proton predicted within this scenario by using a twoloop renormalization group calculation and the ambiguities of O(1) coefficients.
 Publication:

Progress of Theoretical Physics
 Pub Date:
 October 2002
 DOI:
 10.1143/PTP.108.719
 arXiv:
 arXiv:hepph/0205185
 Bibcode:
 2002PThPh.108..719M
 Keywords:

 High Energy Physics  Phenomenology
 EPrint:
 18pages, 1figure, references added, discussion of SUSY threshold added