We analyze ππ-KK and πη-Kk couple channel [1,1] matrix Padé amplitudes of SU(3) × SU(3) chiral perturbation theory.By fitting phase shift and inelasticity data,we determine pole positions in different ch...We analyze ππ-KK and πη-Kk couple channel [1,1] matrix Padé amplitudes of SU(3) × SU(3) chiral perturbation theory.By fitting phase shift and inelasticity data,we determine pole positions in different channels (f 0 (980),a 0 (980),f 0 (600),K*0 (800),K*(892),ρ(770)) and trace their N c trajectories.We stress that a couple channel Breit-Wigner resonance should exhibit two poles on different Riemann sheets and meet each other on the real axis when N c=∞.Poles are hence classified using this criteria and we conclude that K*(892) and ρ(770) are unambiguous Breit-Wigner resonances.For scalars the situation is much less clear.We find that f 0 (980) is a molecular state rather than a Breit-Wigner resonance,while a 0 (980),though behave oddly when varying N c,do maintain a twin pole structure.展开更多
基金Supported by National Natural Science Foundation of China under Grant Nos.10925522,10875001,and 11021092
文摘We analyze ππ-KK and πη-Kk couple channel [1,1] matrix Padé amplitudes of SU(3) × SU(3) chiral perturbation theory.By fitting phase shift and inelasticity data,we determine pole positions in different channels (f 0 (980),a 0 (980),f 0 (600),K*0 (800),K*(892),ρ(770)) and trace their N c trajectories.We stress that a couple channel Breit-Wigner resonance should exhibit two poles on different Riemann sheets and meet each other on the real axis when N c=∞.Poles are hence classified using this criteria and we conclude that K*(892) and ρ(770) are unambiguous Breit-Wigner resonances.For scalars the situation is much less clear.We find that f 0 (980) is a molecular state rather than a Breit-Wigner resonance,while a 0 (980),though behave oddly when varying N c,do maintain a twin pole structure.
