We show that a model with a scalar leptoquark of hypercharge Y = 1/6 which includes the light right-handed neutrinos, can successfully describe both of the B-physics anomalies. We discuss the corresponding low energy effective theory and, after using the known experimental data as constraints, we show that the model is viable and that it offers several predictions which can be tested experimentally.
COBISS.SI-ID: 30095911
Leptoquarks are hypothetical particles that posses spin 0 or 1 and can switch between quarks and leptons, contrary to the already discovered bosons. Their existence is predicted by Grand unified theories where quarks and leptons are treated on equal footing. In the invited review article we have prepared an overview of leptoquark physics. The discussion tackles Standard Model extensions. We present limits on masses and couplings obtained from precise measurements of observables at low energies, such as electric and dipole moments of fermions, parity violation in atoms, neutral meson mixing, decays of K, D, and B mesons and rare decays of leptons. We conclude by presenting current bounds coming from direct searches of leptoquarks at colliders, including the latest theoretical predictions for leptoquark pair creation in hadron colliders.
COBISS.SI-ID: 29636903
The scalar sector of the minimal Left-Right model at TeV scale is revisited in light of the large quartic coupling needed for a heavy flavor-changing scalar. The stability and perturbativity of the effective potential is discussed and merged with constraints from low-energy processes. Thus the perturbative level of the Left-Right scale is sharpened. Lower limits on the triplet scalars are also derived: the left-handed triplet is bounded by oblique parameters, while the doubly-charged right- handed component is limited by the h → γγ, Zγ decays. Current constraints disfavor their detection as long as WR is within the reach of the LHC.
COBISS.SI-ID: 29665831
We analysed the experimental hints of a diphoton resonance in the photon invariant mass at 750 GeV in terms of a new boson, extracting information on its properties and exploring theoretical interpretations.
COBISS.SI-ID: 29401383
A discovery of an intriguing exotic hadron X(5568), composed of four quarks with different flavors b,s,d and u, was reported by the D0 experiment in early 2016. We presented the first ab-initio theoretical study of the corresponding scattering channel Bsπ+ by means of the lattice QCD simulation. We did not find a candidate for this hadron, in agreement with the high-statistic LHCb experiment which reported the results after we reachd our conclusions.
COBISS.SI-ID: 3028836