96 citations · 740 across the 17 of their papers we have counts for
4 papers · 1 filter
String-derived MSSM vacua with residual R symmetries
Rolf Kappl, Bjoern Petersen, Stuart Raby +3
Recently it was shown that there is a unique Z_4^R symmetry for the MSSM which allows the Yukawa couplings and dimension five neutrino mass operator, forbids the mu term and commut…
Quark mass hierarchies in heterotic orbifold GUTs
Rolf Kappl
We discuss how to calculate Yukawa couplings in string-derived orbifold GUTs. As an application we investigate the quark mass hierarchies in these models. An interplay of different…
Light dark matter in the singlet-extended MSSM
Rolf Kappl, Michael Ratz, Martin Wolfgang Winkler
We discuss the possibility of light dark matter in a general singlet extension of the MSSM. Singlino LSPs with masses of a few GeV can explain the signals reported by the CRESST, C…
Approximate R-symmetries and the mu term
Felix Brummer, Rolf Kappl, Michael Ratz +1
We discuss the role of approximate U(1)_R symmetries for the understanding of hierarchies in Nature. Such symmetries may explain a suppressed expectation value of the superpotentia…