English

Leptophobic $Z'$ in stringy flipped SU(5)

High Energy Physics - Phenomenology 2009-10-28 v3 High Energy Physics - Theory

Abstract

We show that leptophobic ZZ' gauge bosons occur naturally in flipped SU(5) and may shift RbR_b in an interesting way without upsetting the good values of Γhad\Gamma_{had} and RcR_c. Within a string-derived version of the model, we study three possible scenarios and the constraints imposed on model building that would allow the new symmetry to remain unbroken down to low energies. Such ZZ' gauge boson has generation non-universal couplings to quarks that violate parity maximally in the up-quark sector, and may contribute significantly to spin asymmetries in polarized pppp scattering experiments now being prepared for RHIC.

Keywords

Cite

@article{arxiv.hep-ph/9605359,
  title  = {Leptophobic $Z'$ in stringy flipped SU(5)},
  author = {J. Lopez and D. Nanopoulos},
  journal= {arXiv preprint arXiv:hep-ph/9605359},
  year   = {2009}
}

Comments

22 pages, LaTeX, 3 figures (included). Final version to appear in Phys. Rev. D. Includes discussion on how to avoid potential FCNC problems and updated data on R_b and R_c

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