Evidence for a vector charmoniumlike state in e + e − → D + s D ∗ s 2 ( 2573 ) − + c . c .

Abstract

We report the measurement of e(+) e(-) -> D-s(+) Ds(2)*(2573)(-) c.c. via initial-state radiation using a data sample of an integrated luminosity of 921.9 fb(-1) collected with the Belle detector at the Upsilon(4S) and nearby. We find evidence for an enhancement with a 3.4 sigma significance in the invariant mass of Ds+Ds2*(2573)(-) + c.c. The measured mass and width are (4619.8(-8.0)(+8.9)(stat.) +/- 2.3(syst.)) MeV/c(2) and (47.0(-14.8)(+31.3)(stat.) +/- 4.6(syst.)) MeV, respectively. The mass, width, and quantum numbers of this enhancement are consistent with the charmoniumlike state at 4626 MeV/c(2) recently reported by Belle in e(+) e(-) -> Ds+ Ds1(2536)(-) c.c. The product of the e(+) e(-) -> D-s(+) Ds(2)*(2573)(-) + c.c. cross section and the branching fraction of D-s2*(2573)(-) -> (D) over bar K-0(-) is measured from Ds+Ds2*(2573)(-) threshold to 5.6 GeV.