Related papers: Hadron Spectroscopy, exotics and $B_c^+$ physics a…
I review here the most recent results about the observation and the study of hadronic bound states that do not fit well in the standard quarkonium picture. Several new states have been observed in the last few years, at B-, tau-Factories…
Hadron spectroscopy provides direct physical measurements that shed light on the non-perturbative behavior of quantum chromodynamics (QCD). In particular, various exotic hadrons such as the newly observed $T_{cc}^+$ by the LHCb…
The classical quenched quark models with three constituent quarks provide a good description for the baryon spatial ground states, but fail to reproduce the spectrum of baryon excited states. More and more evidences suggest that unquenched…
The exciting discovery by LHCb of the $P_c(4312)^+$ and $P_c(4450)^+$ pentaquarks, or the suggestion of a tetraquark nature for the $Z_c(3900)$ state seen at BESIII and Belle, have triggered a lot of activity in the field of hadron physics,…
The $X(6900)$ resonance, very recently discovered in the double-$J/\psi$ channel at LHCb experiment, has spurred intensive interest in unravelling the nature of the fully charmed tetraquark state. The aim of this paper is to present a…
Precision measurements in weak decays of heavy flavored hadrons can test in unique ways our understanding of the fundamental interactions and of the observed baryon asymmetry in the Universe. The high sensitivity of such decays to…
LHCb is one of the four major experiments that will take data at the LHC, due to start operation in 2007. The primary aims of LHCb are to perform precision tests of CP violation and to search for new physics in b hadron decays. About 10^12…
We perform the first model independent analysis of experimental data using Deep Neural Networks to determine the nature of an exotic hadron. Specifically, we study the line shape of the $P_c(4312)$ signal reported by the LHCb collaboration…
Recently a novel hadronic state of mass 6.9 GeV, that decays mainly to a pair of charmonia, was observed in LHCb. The data also reveals a broader structure centered around 6490 MeV and suggests another unconfirmed resonance centered at…
Rare decays of heavy-flavoured particles provide an ideal laboratory to look for deviations from the Standard Model, and explore energy regimes beyond the LHC reach. Decays proceeding via electroweak penguin diagrams are excellent probes to…
Recently several experiments have reported evidences for pentaquark $\Theta^+$. H1 experiment at HERA-B has also reported evidence for $\Theta_c$. $\Theta^+$ is interpreted as a bound state of an $\bar s$ with other four light quarks $udud$…
Studying scattering of heavy flavor hadrons and looking for bound states is shown to give experimental information otherwise unobtainable about effective two-body interactions between constituent $(qq)_6$ and $(\bar qq)_8$ pairs…
With the discovery of new states in recent years, interest in spectroscopy has revived. Recent experimental results in heavy flavour spectroscopy are reviewed, including charmonium, bottomonium, charmed mesons and baryons and bottom mesons.
Three hidden-charm pentaquark $P_c$ states, $P_c(4312)$, $P_c(4440)$, and $P_c(4457)$ were revealed in the $\Lambda_b^0\to J/\psi p K^-$ process measured by LHCb using both run I and run II data. Their nature is under lively discussion, and…
The experimental status of stable bound states made out of heavy quarks is reviewed. The need for a way to deal with the non-perturbative transitions involved calls for precision measurements on one hand, and for discovery of as yet…
Using new experimental data on photoproduction and $\Lambda_b^0$ decays, we derive constraints on the properties of the LHCb $P_c$ states. We conclude that $P_c(4312)$, $P_c(4380)$ and $P_c(4440)$ can be described as $\Sigma_c\bar D$,…
We review the experimental progress on the study of light and heavy hadrons and focus on recent discoveries of the XYZ states, pentaquark states, $T_{cs}$ and $T_{cc}$ states in the heavy hadron sector, and on the $\pi_1(1600)$ and the…
Lattice QCD approach to study the hadronic resonances and exotic hadrons is described at an introductory level. The main challenge is that these states decay strongly via one or more decay channels, and they often lie near thersholds.…
The 2015 LHCb discovery of a structure (denoted by $P_c^+$) decaying in $J/\psi \,p$ and conjectured to be a penta-quark state, has triggered a renewed interest in the question of possible existence of multi-quark states not predicted by…
We perform a theoretical analysis of the $\Lambda_b \to J/\psi K^- p$ reaction from where a recent LHCb experiment extracts a $\Lambda(1405)$ contribution in the $K^- p$ spectrum close to threshold and two baryon states of hidden charm in…