Toward charged $$Z_{cs}(3985)$$ structure under a reflection mechanism

Very recently, the BESIII Collaboration reported a charged hidden-charm structure with strangeness in the recoil mass of $$K^+$$ K + of a process $$e^+e^-\rightarrow D_s^{*-}D^0K^+$$ e + e - → D s ∗ - D 0 K + or $$D_s^{-}D^{*0}K^+$$ D s - D ∗ 0 K + , which is named as $$Z_{cs}(3985)^{-}$$ Z cs ( 3985 ) - . The newly observed charged structure can be treated as a partner structure with strangeness of well-known $$Z_{c}(3885)^{-}$$ Z c ( 3885 ) - reported in a process $$e^+e^-\rightarrow D^{*-}D^0\pi ^+$$ e + e - → D ∗ - D 0 π + . In this work, we propose a reflection picture to understand the nature of $$Z_{cs}(3985)$$ Z cs ( 3985 ) . By performing a combined analysis for the line shape of the recoil mass distribution of $$K^+$$ K + at five energy points $$\sqrt{s}=4.628, 4.641, 4.661, 4.681, 4.698$$ s = 4.628 , 4.641 , 4.661 , 4.681 , 4.698 GeV, we find that the $$Z_{cs}(3985)$$ Z cs ( 3985 ) can be explained as a reflection structure of charmed-strange meson $$D_{s2}^{*}(2573)$$ D s 2 ∗ ( 2573 ) , which is produced from the open-charm decay of Y(4660) with a $$D_s^*$$ D s ∗ meson. Furthermore, we predicted the angular distribution of final state $$D_s^{*-}$$ D s ∗ - in process $$e^+e^-\rightarrow D_s^{*-}D^0K^+$$ e + e - → D s ∗ - D 0 K + based on our proposed reaction mechanism, which may be an essential criterion to test the non-resonant nature of $$Z_{cs}(3985)$$ Z cs ( 3985 ) further.

Recent results of the hadronic cross section measurements with the CMD-3 detector at e+e− collider VEPP-2000

A brief review of the recent results on the hadronic cross section measurements with the CMD-3 detector at the e+e− collider VEPP-2000 is given. Focus is made on the processes with charged kaons in multihadron events, which have a strong impact on strange meson spectroscopy and form factors that are important ingredients in the Dalitz plot analysis. Experimental data relevant to the topic are presented from the broad energy range covered by VEPP-2000 and compared to earlier measurements by the different collaborations. The analysis is based on the integrated luminosity of about 100 pb−1 collected in 2011, 2012 and 2017.