The hidden-charm pentaquark and tetraquark states

QCD factorization for exclusive non-leptonic B-meson decays: General arguments and the case of heavy-light final states

http://fafnir.phyast.pitt.edu/py3765/walkingTCReview.pdf

Strong dynamics and electroweak symmetry breaking

We briefly review how nonrelativistic effective field theories give us a definition of the QCD potentials and a coherent field-theory-derived quantum-mechanical scheme to calculate the properties of bound states made by two or more heavy quarks. In this framework heavy quarkonium properties depend only on the QCD parameters (quark masses and αs) and nonpotential corrections are systematically accounted for. The relation between the form of the nonperturbative potentials and the low-energy QCD dynamics is also discussed.

/pdf/effective-field-theories-for-heavy-quarkonium-1h7nywv4aj.pdf

Effective field theories for heavy quarkonium

Multiquark resonances are undoubtedly experimentally observed The number of states and the amount of details on their properties has been growing over the years It is very recent the discovery of two pentaquarks and the confirmation of four tetraquarks, two of which had not been observed before We mainly review the theoretical understanding of this sector of particle physics phenomenology and present some considerations attempting a coherent description of the so called X and Z resonances The prominent problems plaguing theoretical models, like the absence of selection rules limiting the number of states predicted, motivate new directions in model building Data are reviewed going through all of the observed resonances with particular attention to their common features and the purpose of providing a starting point to further research

/pdf/multiquark-resonances-52gbqrdt0p.pdf

Multiquark Resonances

Phenomenology of heavy meson chiral lagrangians

The approximate symmetries of Quantum ChromoDynamics in the infinite heavy quark ($Q=c,b$) mass limit ($m_Q \to \infty$) and in the chiral limit for the light quarks ($m_q \to 0,\;q=\,u,\,d,\,s$) can be used together to build up an effective chiral lagrangian for heavy and light mesons describing strong interactions among effective meson fields as well as their couplings to electromagnetic and weak currents, including the relevant symmetry breaking terms. The effective theory includes heavy ($Q \bar q$) mesons of both negative and positive parity, light pseudoscalars, as well as light vector mesons. We summarize the estimates for the parameters entering the effective lagrangian and discuss in particular some phenomenologically important couplings, such as $g_{B^* B \pi}$. The hyperfine splitting of heavy mesons is discussed in detail. The effective lagrangian allows for the possibility to describe consistently weak couplings of heavy ($B,\, D$) to light ($\pi,\, \rho, \, K^*,\,$ etc.) mesons. The method has however its own limitations, due to the requirement that the light meson momenta should be small, and we discuss how such limitations can be circumvented through reasonable ansatz on the form factors. Flavour conserving (e. g. $B^* \to B\, \gamma$) and flavour changing (e. g. $B \to K^* \, \gamma$) radiative decays provide another field of applications of effective lagrangians; they are discussed together with their phenomenological implications. Finally we analyze effective lagrangians describing heavy charmonium- like ($\bar Q Q$) mesons and their strong and electromagnetic interactions. The role of approximate heavy quark symmetries for this case and the phenomenological tests of these models are also discussed.

Phenomenology of Heavy Meson Chiral Lagrangians

https://archive-ouverte.unige.ch/unige:91487/ATTACHMENT01

Effective lagrangian for heavy and light mesons. Semileptonic decays

https://archive-ouverte.unige.ch/unige:91545/ATTACHMENT01

Two body non-leptonic decays of B and Bs mesons

https://archive-ouverte.unige.ch/unige:91096/ATTACHMENT01

N. Di Bartolomeo

Papers

Phenomenology of heavy meson chiral lagrangians

Phenomenology of Heavy Meson Chiral Lagrangians

Effective lagrangian for heavy and light mesons. Semileptonic decays

Two body non-leptonic decays of B and Bs mesons

Light vector resonances in the effective chiral lagrangian for heavy mesons