Measurement of the cross section of $$ {e}^{+}{e}^{-}\to {\Xi}^{-}{\overline{\Xi}}^{+} $$ at center-of-mass energies between 3.510 and 4.843 GeV
M. Ablikim, М. Н. Ачасов, P. Adlarson, X. C. Ai, R. Aliberti, A. Amoroso, M. R. An, Qingsong An, Y. Bai, O. Bakina, I. Balossino, Y. Ban, V. Batozskaya, K. Begzsuren, N. Berger, M. Berlowski, M. Bertani, D. Bettoni, F. Bianchi, E. Bianco, A. Bortone, I. Boyko, R. A. Briere, A. Brueggemann, H. Cai, X. Cai, A. Calcaterra, G. F. Cao, N. Cao, S. A. Çetin, J. F. Chang, T. T. Chang, W. L. Chang, G. R., G. Chelkov, C. Chen, Chao Chen, G. Chen, H. S. Chen, Ming Chen, S. J. Chen, S. M. Chen, T. Chen, X. R. Chen, X. T. Chen, Y. B. Chen, Y. Q. Chen, Zixin Chen, W. S. Cheng, S. K. Choi, X. Chu, G. Cibinetto, S. C. Coen, F. Cossio, J. J. Cui, H. L. Dai, J. P. Dai, A. Dbeyssi, R. E. de Boer, D. Dedovich, Z. Y. Deng, A. Denig, I. Denysenko, M. Destefanis, F. De Mori, B. Ding, X. X. Ding, Y. Ding, Y. Ding, J. Dong, L. Y. Dong, M. Y. Dong, Xu Dong, M. C. Du, S. X. Du, Z. H. Duan, P. Egorov, Y. H. Y. Fan, Y. L. Fan, J. Fang, S. S. Fang, W. X. Fang, Y. Fang, R. Farinelli, L. Fava, F. Feldbauer, G. Felici, C. Q. Feng, J. H. Feng, K Fischer, M. Fritsch, C. Fritzsch, C. D. Fu, J. Fu, Y. Fu, H. Gao, Y. N. Gao, Yang Gao, S. Garbolino, I. Garzia
Abstract
A bstract Using e + e − collision data corresponding to a total integrated luminosity of 12.9 fb − 1 collected with the BESIII detector at the BEPCII collider, the exclusive Born cross sections and the effective form factors of the reaction $$ {e}^{+}{e}^{-}\to {\Xi}^{-}{\overline{\Xi}}^{+} $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msup> <mml:mi>e</mml:mi> <mml:mo>+</mml:mo> </mml:msup> <mml:msup> <mml:mi>e</mml:mi> <mml:mo>−</mml:mo> </mml:msup> <mml:mo>→</mml:mo> <mml:msup> <mml:mi>Ξ</mml:mi> <mml:mo>−</mml:mo> </mml:msup> <mml:msup> <mml:mover> <mml:mi>Ξ</mml:mi> <mml:mo>¯</mml:mo> </mml:mover> <mml:mo>+</mml:mo> </mml:msup> </mml:math> are measured via the single baryon-tag method at 23 center-of-mass energies between 3.510 and 4.843 GeV. Evidence for the decay $$ \psi (3770)\to {\Xi}^{-}{\overline{\Xi}}^{+} $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>ψ</mml:mi> <mml:mfenced> <mml:mn>3770</mml:mn> </mml:mfenced> <mml:mo>→</mml:mo> <mml:msup> <mml:mi>Ξ</mml:mi> <mml:mo>−</mml:mo> </mml:msup> <mml:msup> <mml:mover> <mml:mi>Ξ</mml:mi> <mml:mo>¯</mml:mo> </mml:mover> <mml:mo>+</mml:mo> </mml:msup> </mml:math> is observed with a significance of 4.5 σ by analyzing the measured cross sections together with earlier BESIII results. For the other charmonium(-like) states ψ (4040), ψ (4160), Y (4230), Y (4360), ψ (4415), and Y (4660), no significant signal of their decay to $$ {\Xi}^{-}{\overline{\Xi}}^{+} $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msup> <mml:mi>Ξ</mml:mi> <mml:mo>−</mml:mo> </mml:msup> <mml:msup> <mml:mover> <mml:mi>Ξ</mml:mi> <mml:mo>¯</mml:mo> </mml:mover> <mml:mo>+</mml:mo> </mml:msup> </mml:math> is found. For these states, upper limits of the products of the branching fraction and the electronic partial width at the 90% confidence level are provided.