Speaker
Kai Xu
(Suranaree University of Technology)
Description
$N(1685)$ was firstly reported in the photoproduction of $\eta$ meson off the quasi-free neutron. Unlike other low-lying nucleon resonances whose Breit-Wigner (BW) widths are at least $100 {\;\rm MeV}$, the BW width of the $N(1685)$ is less than $30 {\;\rm MeV}$. The interpretation of the $N(1685)$ is still an open question.
The non-strange pentaquark mass of all quark configurations is evaluated in a constituent quark model, where the Cornell potential is employed and all model parameters
are predetermined by comparing the theoretical and experimental masses of low-lying baryons which are believed to be mainly $3q$ states. The state with the $[31]_{FS}[22]_{F}[31]_{S}(q^4 \overline q)$ configuration and quantum numbers $I(J^P)=\frac1{2}(\frac1{2}^{-})$ is predicted to be the lowest pentaquark state. Its mass is derived about $1670 {\;\rm MeV}$, which encourages one to expect that the $N(1685)$ could be the lowest pentaquark state.
Primary author
Kai Xu
(Suranaree University of Technology)
Co-authors
Attaphon Kaewsnod
(S)
Mr
Sorakrai Srisuphaphon
(Department of Physics, Faculty of Science, Burapha University, Chonburi 20131, Thailand)
Yupeng Yan
(Suranaree University of Technology)
