Calculation of the top quark mass in the flipped SU (5) × U (1) superstring model
Abstract
We present a complete renormalization group calculation of the topquark mass in the SU (5) × U (1) superstring model. We solve the coupled renormalization group equations for the gauge and Yukawa couplings in the twoloop approximation and obtain the topquark mass as a function of two parameters of the model which could be chosen to be ratios of singlet VEVs associated with the surplus [U (1)]^{4} breaking. We obtain a heavy topquark with 150 GeV<=m_{t}<200 GeV, for most part of the parameter space, while lower values are possible only in a very small extremal region. We also compute the allowed range of unification parameters [M_{x}, sin^{2}θ_{w}, α_{3}(M_{W})] in the presence of a heavy topquark.
 Publication:

Physics Letters B
 Pub Date:
 November 1990
 DOI:
 10.1016/03702693(90)90235X
 Bibcode:
 1990PhLB..251...83L