The pole structures of the $X(1840)/X(1835)$ and the $X(1880)$

Peng-Yu Niu, Zhen-Yu Zhang, Yi-Yao Li +2

Whether the $N\bar{N}$ interaction could form a state or not is a long standing question, even before the observation of the $p\bar{p}$ threshold enhancement in 2003. The recent hi…