English

Implications of the CMS search for W_R on Grand Unification

High Energy Physics - Phenomenology 2016-03-14 v2

Abstract

The CMS experiment at the Large Hadron Collider has reported a 2.8σ\sigma excess in the (2e)(2jets)(2e)(2jets) channel around 2.1 TeV. Interpretation of this data is reconsidered in terms of the production of a right-handed weak gauge boson, WRW_R, of the left-right symmetric model and in an SO(10)SO(10) grand unified theory abiding by the Extended Survival Hypothesis. The left-right symmetric model can be consistent with this excess if (a) the heavy right-handed neutrino has a mass near WRW_R, or (b) if gLgRg_L \neq g_R, or (c) the right-handed CKM matrix is nontrivial. Combinations of the above possibilities are also viable. A WRW_R with a mass in the TeV region if embedded in SO(10)SO(10) is not compatible with gL=gRg_L = g_R. Rather, it implies 0.64gR/gL0.780.64 \leq g_R/g_L \leq 0.78. Further, a unique symmetry-breaking route -- the order being left-right discrete symmetry breaking first, followed by SU(4)CSU(4)_C and finally SU(2)RSU(2)_R -- to the standard model is picked out. The LRL \leftrightarrow R discrete symmetry has to be broken at around 101610^{16} GeV. The grand unification scale is pushed to 101810^{18} GeV making the detection of proton decay in ongoing searches rather unlikely. The SU(4)CSU(4)_C breaking scale can be at its allowed lower limit of 10610^6 GeV so that nnˉn - \bar{n} oscillation or flavour changing processes such as KLμeK_L \rightarrow \mu e and Bd,sμeB_{d,s} \rightarrow \mu e may be detectable. The Higgs scalar multiplets responsible for SO(10)SO(10) symmetry breaking at various stages are uniquely identified so long as one adheres to a minimalist principle. We also remark, {\em en passant}, about a partially unified Pati-Salam model.

Keywords

Cite

@article{arxiv.1509.03232,
  title  = {Implications of the CMS search for W_R on Grand Unification},
  author = {Triparno Bandyopadhyay and Biswajoy Brahmachari and Amitava Raychaudhuri},
  journal= {arXiv preprint arXiv:1509.03232},
  year   = {2016}
}

Comments

21 pages, v2: Published version. Clarifications and references added