Related papers: Recent Results on Light Meson Physics
Although studied for many years the nature of the light scalar mesons remains controversial. Here we shall present a method, applicable for s-wave states located close to a threshold, that allows one to quantify the molecular part of a…
Three recent results from the ATLAS experiment at the LHC are presented. A new excited heavy meson state is observed through its hadronic transition to the ground state. The production cross-section of B+ mesons is measured as a function of…
A search for new scalar particles of $\mathcal{O}$(GeV) mass in exclusive final states with muons and light hadrons is presented. The analysis uses proton-proton collision data produced at a center-of-mass energy of 13 TeV collected by the…
Lattice QCD with $N_f=2$ flavours of sea quark is used to explore the spectrum and decay of scalar mesons. We are able to determine the $b_1$ - $a_0$ mass difference and this leads to the conclusion that the lightest non-singlet scalar…
Low energy precision experiments provide significant tests of the laws of nature that can reveal physics beyond the Standard Model. A good theoretical understanding of the low energy properties of QCD is required for this purpose. The…
We summarize the current theoretical and experimental status of the spectral changes of vector mesons ($\rho$, $\omega$, $\phi$) at finite baryon density. Various approaches including QCD sum rules, effective theory of hadrons and bag…
Two-photon decays of light scalar mesons are discussed within the quarkonium and tetraquark asignements: in both cases the decay rate of the sigma resonances turns out to be smaller than 1 keV.
We present evidence for the existence of a light scalar particle that most probably couples exclusively to gluons and quarks. Theoretical and phenomenological arguments are presented to support the existence of a light scalar boson for…
Recent BABAR results on two-photon processes are presented. A high statistics study of the two-photon production of the charmonium states eta_c and eta_c(2S) is performed. The mass and width of eta_c and eta_c(2S) are measured; the ratio of…
Recent results on the study of the electromagnetic structure of nucleon resonances, the spin structure of proton and neutrons at small and intermediate photon virtualities, and the search for exotic pentaquark baryons are presented.
In the past few years there has been a great deal of theoretical and experimental activity related to the search for low-mass scalars, pseudoscalars, and vectors in various scenarios of physics beyond the standard model. I review the…
We review the present understanding of etaprime and eta meson physics and these mesons as a probe of gluon dynamics in low-energy QCD. Recent highlights include the production mechanism of eta and etaprime mesons in proton-nucleon…
We study the decay modes of a new, light spin-0 particle, arguing that if the mass of the (pseudo)scalar is ~11-15 GeV, it can have an appreciable branching ratio into bottomonium, in particular the rare eta's. Using non-relativistic QCD…
We present the most recent results from the BESIII experiment. This review covers the studies of charmonium decays, light hadron spectroscopy and charm physics. Especially, the prospects for weak decays of charm mesons are addressed at the…
We present a brief account of the developments in the description of light meson resonances using unitarized extensions of the Chiral Perturbation Theory series, both in energy and temperature. In particular, we describe how these methods…
We study the properties of the light pseudoscalar mesons in a three flavor chiral quark model with nonlocal separable interactions. We concentrate on the evaluation of meson masses and decay constants, considering both the cases of Gaussian…
Results on light scalar mesons in charmed particle decays studied by the CLEO Collaboration at the Cornell Electron Storage Ring are reviewed.
Weak decays of charm mesons has been used for studies of light quark spectroscopy, with particular emphasis on the J^{PC}=0^{++} states. Recent results on light scalars are summarized and some conceptual issues are discussed, especially the…
We describe the status of the analyses in progress on light meson spectroscopy in the KLOE experiment. We present the analyses of phi decays into f0(980)gamma and a0(980)gamma, the Dalitz plot analysis of the eta to pie+ pie- pie0 decay,…
The origin of the lightest scalar mesons is studied in the framework of instanton liquid model (ILM) of the QCD vacuum. The impact of vacuum excitations on the sigma-meson features is analyzed in detail. In particular, it is noticed that…