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Title: Flavor-changing neutral current effects and CP violation in the minimal 3-3-1 model

Abstract

We investigate in detail the flavor structure of the minimal 3-3-1 model and its implications for several flavor-changing neutral current (FCNC) processes. In this model, where the weak SU(2){sub L} gauge group of the Standard Model is extended to a SU(3){sub L}, the by far dominant new contributions come from an additional neutral Z{sup '} gauge boson, that can transmit FCNCs at tree-level. At the same time, electroweak precision observables receive new contributions only at the loop level and do not constrain the model very strongly. In our analysis, we take into account new CP-violating effects that have been neglected in earlier analyses, and account for a general flavor structure without reference to a certain parametrization of the new mixing-matrix. We begin by studying the bounds obtained from quantities such as {delta}M{sub K}, {epsilon}{sub K}, {delta}M{sub d/s} as well as sin2{beta}|{sub J/{psi}}{sub K{sub S}}, and go on to explore the implications for several clean rare decay channels, namely, the decays K{sup +}{yields}{pi}{sup +}{nu}{nu}, K{sub L}{yields}{pi}{sup 0}{nu}{nu}, B{sub d/s}{yields}{mu}{sup +}{mu}{sup -} and K{sub L}{yields}{pi}{sup 0}l{sup +}l{sup -}. We find sizeable effects in all these decays, but the most interesting quantity turns out to be the B{sub s}{sup 0}-B{sub s}{sup 0} mixingmore » phase {beta}{sub s}, as measured in the mixing induced CP asymmetry of B{sub s}{sup 0}{yields}J/{psi}{phi}, which can be large. In general, we find effects in purely hadronic channels to be larger than in (semi-)leptonic ones, due to a suppression of the Z{sup '}-lepton couplings.« less

Authors:
;  [1];  [2]
  1. Physik Department, Technische Universitaet Muenchen, D-85748 Garching (Germany)
  2. Departament de Fisica Teorica, IFAE, UAB, E-08193 Bellaterra, Barcelona (Spain)
Publication Date:
OSTI Identifier:
20929569
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 11; Other Information: DOI: 10.1103/PhysRevD.75.115007; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ASYMMETRY; CP INVARIANCE; FLAVOR MODEL; GAUGE INVARIANCE; J PSI-3097 MESONS; KAONS NEUTRAL LONG-LIVED; KAONS PLUS; MUONS MINUS; MUONS PLUS; NEUTRAL CURRENTS; NEUTRINOS; PAIR PRODUCTION; PARTICLE DECAY; PHI MESONS; PIONS NEUTRAL; PIONS PLUS; STANDARD MODEL; Z NEUTRAL BOSONS

Citation Formats

Promberger, Christoph, Schatt, Sebastian, and Schwab, Felix. Flavor-changing neutral current effects and CP violation in the minimal 3-3-1 model. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.115007.
Promberger, Christoph, Schatt, Sebastian, & Schwab, Felix. Flavor-changing neutral current effects and CP violation in the minimal 3-3-1 model. United States. doi:10.1103/PHYSREVD.75.115007.
Promberger, Christoph, Schatt, Sebastian, and Schwab, Felix. Fri . "Flavor-changing neutral current effects and CP violation in the minimal 3-3-1 model". United States. doi:10.1103/PHYSREVD.75.115007.
@article{osti_20929569,
title = {Flavor-changing neutral current effects and CP violation in the minimal 3-3-1 model},
author = {Promberger, Christoph and Schatt, Sebastian and Schwab, Felix},
abstractNote = {We investigate in detail the flavor structure of the minimal 3-3-1 model and its implications for several flavor-changing neutral current (FCNC) processes. In this model, where the weak SU(2){sub L} gauge group of the Standard Model is extended to a SU(3){sub L}, the by far dominant new contributions come from an additional neutral Z{sup '} gauge boson, that can transmit FCNCs at tree-level. At the same time, electroweak precision observables receive new contributions only at the loop level and do not constrain the model very strongly. In our analysis, we take into account new CP-violating effects that have been neglected in earlier analyses, and account for a general flavor structure without reference to a certain parametrization of the new mixing-matrix. We begin by studying the bounds obtained from quantities such as {delta}M{sub K}, {epsilon}{sub K}, {delta}M{sub d/s} as well as sin2{beta}|{sub J/{psi}}{sub K{sub S}}, and go on to explore the implications for several clean rare decay channels, namely, the decays K{sup +}{yields}{pi}{sup +}{nu}{nu}, K{sub L}{yields}{pi}{sup 0}{nu}{nu}, B{sub d/s}{yields}{mu}{sup +}{mu}{sup -} and K{sub L}{yields}{pi}{sup 0}l{sup +}l{sup -}. We find sizeable effects in all these decays, but the most interesting quantity turns out to be the B{sub s}{sup 0}-B{sub s}{sup 0} mixing phase {beta}{sub s}, as measured in the mixing induced CP asymmetry of B{sub s}{sup 0}{yields}J/{psi}{phi}, which can be large. In general, we find effects in purely hadronic channels to be larger than in (semi-)leptonic ones, due to a suppression of the Z{sup '}-lepton couplings.},
doi = {10.1103/PHYSREVD.75.115007},
journal = {Physical Review. D, Particles Fields},
number = 11,
volume = 75,
place = {United States},
year = {Fri Jun 01 00:00:00 EDT 2007},
month = {Fri Jun 01 00:00:00 EDT 2007}
}
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