2011/04/12 by Luis A. Anchordoqui, Haim Goldberg, Xing Huang +3 · 1 voice · 52 citations
Physics and Astronomy · #Anomaly (physics) #Black Holes and Theoretical Physics #Boson #Branching fraction #Cosmology and Gravitation Theories #Electron #Electroweak interaction #Gauge (firearms) #Gauge boson #Gauge theory #Gluon #Hypercharge #Invariant mass #Large Hadron Collider #Lepton #Nuclear physics #Particle physics #Particle physics theoretical and experimental studies #Physics #Quantum chromodynamics #Standard Model (mathematical formulation) #Superpartner #Supersymmetry #Tevatron #hep-ex #hep-ph #hep-th
paper · pdf · doi:10.1016/j.physletb.2011.05.049
published in Physics Letters B 701(2), 224-228 (Elsevier BV) · v1 8 pages revtex; v2 better fit to the data (Z" within LHC reach), references added; v3 to appear in PLB
arxiv published 2011/04/12 · arxiv created 2011/05/19 · arxiv updated 2011/05/19 · openalex publication_date 2011/05/27 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
The invariant mass distribution of dijets produced in association with W bosons, recently observed by the CDF Collaboration at Tevatron, reveals an excess in the dijet mass range 120-160 GeV/c2, 3σbeyond Standard Model expectations. We show that such an excess is a generic feature of low mass string theory, due to the production and decay of a leptophobic Z', a singlet partner of SU(3) gluons coupled primarily to the U(1) baryon number. In this framework, U(1) and SU(3) appear as subgroups of U(3) associated with open strings ending on a stack of 3 D-branes. In addition, a minimal model contains two other stacks to accommodate the electro-weak SU(2) ∈ U(2) and the hypercharge U(1). Of the three U(1) gauge bosons, the two heavy Z' and Z" receive masses through the Green-Schwarz mechanism. For a given Z' mass, the model is quite constrained. Fine tuning three of its free parameters is just sufficient to simultaneously ensure: a small Z-Z' mixing in accord with the stringent LEP data on the Z mass; very small (less than 1%) branching ratio into leptons; and a large hierarchy between Z" and Z' masses. The heavier neutral gauge boson Z" is within the reach of LHC.