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Using e(+)e(-) collision data collected by the BESIII detector at BEPCII corresponding to an integrated luminosity of 30 fb(-1), we measure Born cross sections and effective form factors for the process e(+)e(-)-> Xi(0)(Xi) over bar (0) at forty-five center-of-mass energies between 3.51 and 4.95 GeV. The dressed cross section is fitted, assuming a power-law function plus a charmonium(-like) state, i.e., psi(3770), psi(4040), psi(4160), psi(4230), psi(4360), psi(4415) or psi(4660). No significant charmonium(-like) state decaying into Xi(0)(Xi) over bar (0) is observed. Upper limits at the 90% confidence level on the product of the branching fraction and the electronic partial width are provided for each decay. In addition, ratios of the Born cross sections and the effective form factors for e(+)e(-) -> Xi(0)(Xi) over bar (0) and e(+)e(-) -> Xi(-)(Xi) over bar (+) are also presented to test isospin symmetry and the vector meson dominance model.
Oleg Yazyev, Yifei Guan, Mitali Banerjee
Tudor Ratiu, François Gay-Balmaz