Related papers: Lepto-mesons, Leptoquarkonium and the QCD Potentia…
In the heavy quark and large Nc limits, ordinary (exotic) heavy baryons can be considered as bound states of heavy mesons (anti-mesons)and chiral solitons. In these limits, the heavy mesons (or anti-mesons) and the chiral solitons are…
We discuss the physics potential of the $\mu p$ collider; especially, leptoquarks, leptogluons, R-parity violating squarks, contact interactions, and large extra dimensions. We calculate the sensitivity reach for these new physics at $\mu…
Lepto-nuclear colliders offer unique experimental opportunities to probe QCD in an extended medium. Of the many possibilities, three experiments are described here that are clearly feasible and of high scientific importance. First, a direct…
Spectrum of the low-lying hidden- and double-charm tetraquark states are investigated in a nonrelativistic quark potential model, where the Instanton-induced interaction is taken as the residual spin-dependent hyperfine interaction between…
The decays and mixing of $K$ mesons are remarkably sensitive to the weak interactions of quarks and leptons at high energies. They provide important tests of the standard model at both first and second order in the Fermi constant $G_F$ and…
We report on a recent QCD based research on hybrid mesons containing $c\bar c$ or $b\bar b$ quarks. We present results for the spectrum, the decay widths to heavy quarkonium, and the role of mixing with the latter. We point out that mixing…
Lepton pairs with opposite charges can form bound states known as ``leptonium'' through quantum electrodynamic interactions. Heavy quarkonia such as $J/\psi$ are abundantly produced at facilities like BESIII and the future Super Tau-Charm…
Prompted by the recent surprising results in QCD spectroscopy, we extend to heavy flavors the hadron mass relations showing that the constituent quark mass differences and ratios have the same values when obtained from mesons and baryons.…
Theoretical descriptions for the nonleptonic decays of heavy flavour hadrons have emerged that incorporate non-perturbative corrections in a systematic way and are genuinely based on QCD. One can reproduce $\tau (D^+)/\tau (D^0)$,…
The results of a previous search by the CMS Collaboration for squarks and gluinos are reinterpreted to constrain models of leptoquark (LQ) production. The search considers jets in association with a transverse momentum imbalance, using the…
Quarkonium resonances in the complex-mass scale are studied. Relativistic quark potential model is used to describe the quark-antiquark system. The complex-mass formula is obtained from two exact asymptotic solutions for the QCD motivated…
We discuss the specific features of extracting properties of the exotic polyquark hadrons (tetraquarks, pentaquarks) compared to the usual hadrons by the QCD sum-rule approach. In the case of the ordinary hadrons, already the one-loop…
We discuss three possible scenarios for the interpretation of mesons containing a heavy quark and its antiquark near and above the first threshold for a decay into a pair of heavy mesons in a relative $S$--wave. View I assumes that these…
Non-relativistic bound state theories for QED and QCD have become fairly mature and amenable to a textbook-level understanding and computation. In this talk we give an introductory review of the following subjects related to the recent…
We study the impact of machine-learning algorithms on LHC searches for leptoquarks in final states with hadronically decaying tau leptons, multiple $b$-jets, and large missing transverse momentum. Pair production of scalar leptoquarks with…
I discuss the investigation of heavy exotic mesons using lattice QCD static potentials and the Born-Oppenheimer approximation. I summarize selected recent results for $\bar{b} \bar{b} q q$ tetraquarks, for $I = 0$ bottomonium and for $I =…
Applying asymptotic expansions at threshold, we compute the two-loop QCD correction to the short-distance coefficient that governs the leptonic decay $\psi\to l^+ l^-$ of a S-wave quarkonium state and discuss its impact on the relation…
The decay rates of $Q \bar Q$ mesons ($Q \varepsilon {c, b}$) are studied in the NRQCD formalism in terms of their short distance and long distance coefficients. The long distance coefficients are obtained through phenomenological potential…
We investigate the discovery potential for first generation leptoquarks at the LEP200 $e^+e^-$ collider. We consider direct leptoquark searches using single leptoquark production via resolved photon contributions which offers a much higher…
Doubly heavy tetraquarks have emerged as new probes to study the heavy hadron spectrum. With the experimental observation of the $J^P=1^+$ $T_{cc}^+$, they pose a unique opportunity to bring together efforts in experiment, phenomenology,…