Determination of spin and parity of the $Z_c(3900)$

BESIII Collaboration, M. Ablikim, M. N. Achasov +424

The spin and parity of the $Z_c(3900{)}^{\pm }$ state are determined to be $J^P=1^{+}$ with a statistical significance larger than $7\sigma$ over other quantum numbers in a partial wave analys…