LHC phenomenology of SO(10) models with Yukawa unification

Abstract

In this paper we study an SO(10) SUSY GUT with Yukawa unification for the third generation. We perform a global χ 2 analysis given to obtain the GUT boundary conditions consistent with 11 low energy observables, including the top, bottom and tau masses. We assume a universal mass, m 16 , for squarks and sleptons and a universal gaugino mass, M 1/2 . We then analyze the phenomenological consequences for the LHC for 15 benchmark models with fixed m 16 = 20 TeV and with varying values of the gluino mass. The goal of the present work is to (i) evaluate the lower bound on the gluino mass in our model coming from the most recent published data of CMS and (ii) to compare this bound with similar bounds obtained by CMS using simplified models. The bottom line is that the bounds coming from the same sign di-lepton analysis are comparable for our model and the simplified model studied assuming B(g → ttχ 0 1 ) = 100%. However the bounds coming from the purely hadronic analyses for our model are 10 -20% lower than obtained for the simplified models. This is due to the fact that for our models the branching ratio for the decayg → gχ 0 1,2 is significant. Thus there are significantly fewer b-jets. We find a lower bound on the gluino mass in our models with Mg 1000 GeV. Finally, there is a theoretical upper bound on the gluino mass which increases with the value of m 16 . For m 16 ≤ 30 TeV, the gluino mass satisfies Mg ≤ 2.8 TeV at 90% CL. Thus, unless we further increase the amount of fine-tuning, we expect gluinos to be discovered at LHC 14.arXiv:1307.7723v2 [hep-ph]

Split sfermion families, Yukawa unification and muon g − 2

“…[19]). As in the previous case, the sfermions from the first and second families have common universal SSB mass terms m The R tbτ − M 1/2 plane shows the same interval for the parameter M 1/2 which is compatible with t-b-τ Yukawa unification as previously found with universal SSB sfermion masses [9][10][11]. This result was expected since the different SSB mass terms for the first/second and the third families do not significantly affect the RGE running and threshold corrections to the third generation fermions which is very crucial for t-b-τ Yukawa unification.…”

“…On the other hand, as we mentioned above, t-b-τ YU requires [9][10][11][12][13][14][15][16][17][18][19] the sleptons to be around a TeV or above, if universality among sfermion masses is assumed at M GUT . Our analysis in the following sections show that the non-universal gaugino case with split family sfermions can resolve the g − 2 discrepancy and also realize t-b-τ Yukawa unification, while staying consistent with all current experimental data.…”

“…To realize a 125 GeV light CP even Higgs boson in this scenario we require Mg ≤ 3 TeV and mb ≥ 10 TeV. This also yields bounds on the fundamental SSB parameters, namely, m 0 10 TeV and M 1/2 1 TeV [9][10][11]. Here m 0 and M 1/2 are GUT scale universal SSB mass terms for the sfermions and gauginos, respectively.…”

“…On the other hand, imposing t-b-τ Yukawa coupling unification condition at M GUT [6][7][8] can place significant constraints on the supersymmetric spectrum in order to fit the top, bottom and tau masses. These constraints are quite severe [9][10][11][12][13][14][15][16][17][18][19], especially after the discovery of a SM like Higgs boson with mass, m h 125 − 126 GeV [20,21].…”

Predicting the sparticle spectrum from GUTs via SUSY threshold corrections with SusyTC

“…Various aspects regarding the impact of such GUT relations for phenomenology have been studied in the literature, see e.g. [14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31] for recent works.…”