arXiv subjects
Publications and source records attributed to Ju-Jun Xie.
The value of the $N^*(1535)Nρ$ coupling constant $g_{N^*Nρ}$ derived from the $N^*(1535) \to Nρ\to N ππ$ decay is compared with that deduced from the radiative decay $N^*(1535) \to N γ$ using the vector-meson-dominance model. On the basis of an effective Lagrangian approach, we show that the value of $g_{N^*Nρ}$ extracted from the available experimental data on the two decays are consistent, though the error bars are rather large.
The strangeness production in heavy ion collisions was proposed to be probes of the nuclear equation of state, Kaon potential in nuclear medium, strange quark matter and quark-gluon plasma, etc. However, to act as reliable probes, proper understanding of the basic ingredients for the strangeness production, such as $pp \to pK^+Λ$, $pp \to pp ϕ$ and $pp \to nK^+Σ^+$ is necessary. Recent study of these reactions clearly shows that previously ignored contributions from the spin-parity $1/2^-$ resonances, $N^*(1535)$ and $Δ^*(1620)$, are in fact very important for these reactions, especially for near-threshold energies. It is necessary to include these contributions for getting reliable calculation for the strangeness production in heavy ion collisions.