Observation of e + e − → π + π − ψ ( 3770 ) and D 1 ( 2420 ) 0 D ¯ 0 + c . c

• Published in: Physical review. D 2019-08, Vol.100 (3), Article 032005
• Main Authors: Ablikim, M., Achasov, M. N., Adlarson, P., Ahmed, S., Albrecht, M., Alekseev, M., Amoroso, A., An, F. F., An, Q., Bai, Y., Bakina, O., Baldini Ferroli, R., Balossino Balossino, I., Ban, Y., Begzsuren, K., Bennett, J. V., Berger, N., Bertani, M., Bettoni, D., Bianchi, F., Biernat, J., Bloms, J., Boyko, I., Briere, R. A., Cai, H., Cai, X., Calcaterra, A., Cao, G. F., Cao, N., Cetin, S. A., Chai, J., Chang, J. F., Chang, W. L., Chelkov, G., Chen, D. Y., Chen, G., Chen, H. S., Chen, J. C., Chen, M. L., Chen, S. J., Chen, Y. B., Cheng, W., Cibinetto, G., Cossio, F., Cui, X. F., Dai, H. L., Dai, J. P., Dai, X. C., Dbeyssi, A., Dedovich, D., Deng, Z. Y., Denig, A., Denysenko, I., Destefanis, M., De Mori, F., Ding, Y., Dong, C., Dong, J., Dong, L. Y., Dong, M. Y., Dou, Z. L., Du, S. X., Fan, J. Z., Fang, J., Fang, S. S., Fang, Y., Farinelli, R., Fava, L., Feldbauer, F., Felici, G., Feng, C. Q., Fritsch, M., Fu, C. D., Fu, Y., Gao, Q., Gao, X. L., Gao, Y., Gao, Y. G., Gao, Z., Garillon, B., Garzia, I., Gersabeck, E. M., Gilman, A., Goetzen, K., Gong, L., Gong, W. X., Gradl, W., Greco, M., Gu, L. M., Gu, M. H., Gu, S., Gu, Y. T., Guo, A. Q., Guo, L. B., Guo, R. P., Guo, Y. P., Guskov, A., Han, S., Hao, X. Q., Harris, F. A.
• Format: Article
• Language: English
• Subjects: astronomy & astrophysics; charmed mesons; physics; PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
• ISSN: 2470-0010; 2470-0029
• DOI: 10.1103/PhysRevD.100.032005

Several intermediate states of the reaction channels e+e– → π+π– D0¯D0 and e+e– → π+π–D+D– are studied using the data samples collected with the BESIII detector at center-of-mass energies above 4.08 GeV. For the first time in this final state, a ψ(3770) signal is seen in the D¯D invariant mass spectrum, with a statistical significance of 5.2σ at √s = 4.42 GeV. There is also evidence for this resonance at √s = 4.26 and 4.36 GeV with statistical significance of 3.2σ and 3.3σ, respectively. In addition, the Born cross section of e+e– → π+π– ψ(3770) is measured.