235 citations · 1.1k across the 21 of their papers we have counts for
4 papers · 1 filter
Four-Quark Hadrons: an Updated Review
Angelo Esposito, Andrea L. Guerrieri, Fulvio Piccinini +2
The past decade witnessed a remarkable proliferation of exotic charmonium-like resonances discovered at accelerators. In particular, the recently observed charged states are clearl…
A note on the newly observed Y(4220) resonance
R. Faccini, G. Filaci, A. L. Guerrieri +2
BES III Collaboration has recently observed a vector resonance in the chi_{c0} omega channel, at a mass of about 4220 MeV, named Y(4220). Hints of a similar structure appear in the…
Probing the nature of Z_c states via the eta_c rho decay
A. Esposito, A. L. Guerrieri, A. Pilloni
The nature of the so-called XYZ states is a long-standing problem. It has been suggested that such particles may be described as compact four-quark states or loosely bound meson mo…
Has the Goldstone theorem been revisited?
A. Guerrieri, A. Pilloni
A recent paper (arXiv:1404.5619) claimed the presence of a loophole in the current-algebra proof of Goldstone Theorem. The enforcing of manifest covariance would lead to contradict…