Amplitude analysis ofK̅ N scattering

The Joint Physics Analysis Center: Recent results

“…In [46] we combined Regge phenomenology [20,37], the information on the hyperon spectrum from [35], and the Λ(1405) pole positions from [47] to gain insight on the nature of the two Λ(1405) states. We found that the higher-mass pole appears to be (mostly) a three-quark hyperon and the lower-mass pole either a molecule or a pentaquark [46,48].…”

“…Resonances of different angular momenta share the same Regge trajectory, what gives the spectrum an organized structure [20,44]. The structure of the spectrum and the shape of the trajectories provide information on the composition of the states [35,42,45,46,48]. In [46] we combined Regge phenomenology [20,37], the information on the hyperon spectrum from [35], and the Λ(1405) pole positions from [47] to gain insight on the nature of the two Λ(1405) states.…”

“…At present we have standing collaborations with BESIII, COMPASS, CLAS, GlueX, KLOE and LHCb. We are focused on hadron spectroscopy delivering amplitudes for three-body meson decays [26,27,28,29,30], meson-baryon scattering [34,35,42,43], Regge phenomenology to gain insight on the internal structure of hadrons [46,48] and meson photoproduction [49,50,51]. Codes for the amplitudes are available either from the JPAC web page [15, 55,56] or upon request.…”

Hidden charm pentaquarks: mass spectrum, magnetic moments and photocouplings

“…The highest deviation (∼ 14%) is observed for the Λ(1405). The Λ(1405) is actually made out of two poles [31,60,61] whose nature is under discussion [56,62]. Some works interpret it to be a molecule [63][64][65] and others favor a compact three-quark state [57,58,[66][67][68][69].…”