Related papers: Probing Quark-Lepton Unification with Leptoquark a…
We study meson decays mediated by the heavy gauge bosons of the Pati-Salam model of quark-lepton unification. We consider the scenarios in which the tau lepton is associated with the third, second, and first generation of quarks. The most…
There is a unique $\hbox{SU(4)}\otimes\hbox{SU(2)}_L \otimes \hbox{SU(2)}_R$ gauge model which allows quarks and leptons to be unified at the TeV scale -- thereby making the model testable and avoiding the gauge hierarchy problem. In its…
We attempt to explain recent anomalies in semileptonic $B$ decays at LHCb via a composite Higgs model, in which both the Higgs and an $SU(2)_L$-triplet leptoquark arise as pseudo-Goldstone bosons of the strong dynamics. Fermion masses are…
In low energy phenomenology to avoid the strong constraints of proton decay it is usually assumed that light ($\approx $ 250 Gev) leptoquarks couple only to quark-lepton pairs and light diquarks couple only to quark pairs. In this work we…
The contributions of the scalar leptoquark doublets into widths of the $K^0_L \to e^{\mp} \mu^{\pm}$, $B^0 \to e^{\mp} \tau^{\pm}$ decays are calculated in MQLS model with Higgs mechanism of the quark-lepton mass splitting. The resulted…
We consider a quark-lepton symmetry model of unification of the strong and electromagnetic interactions. The model has the gauge group $SU(4)\times U(1)_{Y}$ and the minimal Higgs structure consisting of one complex quartet of scalar…
We investigate the quark-lepton symmetric gauge group in five dimensions, with the gauge symmetry broken by a combination of orbifold compactification of the extra dimension and the Higgs mechanism. The gauge sector of the model is…
The collider experiments at the Tevatron and the LHC provide us the possibility of probing the existence of a light charged Higgs boson. In this paper we study semi-leptonic decay of a polarized top quark via the charged Higgs boson…
Identical interactions found in the three families of quarks and leptons suggest the presence of a horizontal symmetry. We discuss how such a symmetry can be tested by measuring the decay rates of Higgs into fermion pairs, and the Higgs…
We study contributions of single scalar or vector leptoquark (LQ) to loop-induced Higgs processes, gluon fusion production ($g g \to h$) and $h \to \gamma \gamma$ decay, by analyzing the current Higgs data from the LHC Run I and II. Scalar…
It was previously noted that SU(5) unification can be achieved via the simple addition of light scalar leptoquarks from two split $\bf10$ multiplets. We explore the parameter space of this model in detail and find that unification requires…
The Higgs boson couplings to bottom and top quarks have been measured and agree well with the Standard Model predictions. Decays to lighter quarks and gluons, however, remain elusive. Observing these decays is essential to complete the…
We relate leptogenesis in a class of theories to low-energy experimental observables: quark and lepton masses and mixings. With reasonable assumptions motivated by grand unification, one can show that the CP-asymmetry parameter takes a…
The production of single and paired lepton bound states in the decay of the Higgs boson has been studied. We explore different decay mechanisms that contribute significantly to the decay width. The decay widths are calculated taking into…
Heavy quarkonium decays can be used to search for New Physics beyond the Standard Model. In particular, a light Higgs boson could induce a slight (but observable) lepton universality breaking in Upsilon decays. In fact, current experimental…
New preliminary combined results from the LEP experiments on searches for the Higgs boson beyond the Standard Model are presented. The new determination of the top quark mass at the Tevatron in 2004 influences the interpretations of the LEP…
The properties of light leptoquarks predicted in the context of a simple grand unified theory and their observability at the LHC are investigated. The SU(5) symmetry of the theory implies that the leptoquark couplings to matter are related…
I study phenomenological aspects of the SU(2)L x U(1) electroweak physics of a Higgs boson transforming like a quark-antiquark pair. A correspondence is established between its flavour content, the hierarchy of quark condensates, and the…
Existence of color sextet diquark Higgs fields with TeV masses will indicate a fundamentally different direction for unification than conventional grand unified theories. There is a class of partial unification models based on the gauge…
Leptoquarks (LQs) are predicted within Grand Unified Theories and are well motivated by the current flavor anomalies. In this article we investigate the impact of scalar LQs on Higgs decays and oblique corrections as complementary…