Observation of the Z_(cs)(3985) Strange Four-quark Meson:The first hidden-charm tetraquark state with non-zero strangeness

In the March 12.2021 issue of Plvvsical Rerievr Letters.the BES111 collaboration reports the.diseovery of an cxolic multiquark strtture,dubsled Z_(cs)(3985).that is produced in the process of e^(+)e^(-)→K+(D_(s)^(-)D^(*0)+D_(s)^(*-)D^(0))at a e+e center-of-mass cneryof+4.68 GeV.