Measurement of e(+)e(-) -> pi(+)pi(-)psi(2S) via initial state radiation at Belle

Wang, X. L.; Yuan, C. Z.; Shen, C. P.; Wang, P.; Abdesselam, A.; Adachi, I.; Aihara, H.; Al Said, S.; Arinstein, K.; Asner, D. M.; Ayad, R.; Bakich, A. M.; Bansal, V.; Bhuyan, B.; Bobrov, A.; Bonvicini, G.; Bracko, M.; Browder, T. E.; Cervenkov, D.; Chang, P.; Chekelian, V.; Chen, A.; Cheon, B. G.; Chilikin, K.; Chistov, R.; Cho, K.; Chobanova, V.; Choi, S. -K.; Choi, Y.; Cinabro, D.; Dalseno, J.; Danilov, M.; Dolezal, Z.; Drasal, Z.; Drutskoy, A.; Dutta, K.; Eidelman, S.; Farhat, H.; Fast, J. E.; Ferber, T.; Gaur, V.; Garmash, A.; Getzkow, D.; Gillard, R.; Goh, Y. M.; Haba, J.; Hayasaka, K.; Hayashii, H.; He, X. H.; Hou, W. -S.; Iijima, T.; Inami, K.; Ishikawa, A.; Itoh, R.; Iwasaki, Y.; Joffe, D.; Julius, T.; Kang, K. H.; Kato, E.; Kawasaki, T.; Kiesling, C.; Kim, D. Y.; Kim, H. J.; Kim, J. B.; Kim, J. H.; Kim, M. J.; Kim, S. H.; Kim, Y. J.; Kinoshita, K.; Ko, B. R.; Kodys, P.; Korpar, S.; Krizan, P.; Krokovny, P.; Kuzmin, A.; Kwon, Y. -J.; Lange, J. S.; Lee, I. S.; Lewis, P.; Li, Y.; Gioi, L. Li; Libby, J.; Liventsev, D.; Lukin, P.; Matvienko, D.; Miyabayashi, K.; Miyata, H.; Mizuk, R.; Moll, A.; Mori, T.; Mussa, R.; Nakano, E.; Nakao, M.; Nanut, T.; Natkaniec, Z.; Nisar, N. K.; Nishida, S.; Ogawa, S.; Okuno, S.; Olsen, S. L.

doi:10.1103/PhysRevD.91.112007

research article

Measurement of e(+)e(-) -> pi(+)pi(-)psi(2S) via initial state radiation at Belle

Wang, X. L.

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Yuan, C. Z.

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Shen, C. P.

2015

Physical Review D [1970-2015]

We report measurement of the cross section of e(+)e(-) -> pi(+)pi(-)psi(2S) between 4.0 and 5.5 GeV, based on an analysis of initial state radiation events in a 980 fb(-1) data sample recorded with the Belle detector. The properties of the Y(4360) and Y(4660) states are determined. Fitting the mass spectrum of pi(+)pi(-)psi(2S) with two coherent Breit-Wigner functions, we find two solutions with identical mass and width but different couplings to electron-positron pairs: M-Y(4360) = (4347 +/- 6 +/- 3) MeV/c(2), Gamma(Y(4360)) = (103 +/- 9 +/- 5) MeV, M-Y(4660) = (4652 +/- 10 +/- 8) MeV/c(2), Gamma(Y(4660)) = (68 +/- 11 +/- 1) MeV; and B[Y(4360) -> pi(+)pi(-)psi(2S)] . Gamma(e+e-)(Y(4360)) = (10.9 +/- 0.6 +/- 0.7) eV and B[Y(4660) -> pi(+)pi(-)psi(2S)] . Gamma(e+e-)(Y(4660)) = (8.1 +/- 1.1 +/- 0.5) eV for one solution; or B[Y(4360) -> pi(+)pi(-)psi(2S)] . Gamma(e+e-)(Y(4360)) = (9.2 +/- 0.6 +/- 0.6) eV and B[Y(4660) -> pi(+)pi(-)psi(2S)] . Gamma(e+e-)(Y(4660)) = (2.0 +/- 0.3 +/- 0.2) eV for the other. Here, the first errors are statistical and the second systematic. Evidence for a charged charmoniumlike structure at 4.05 GeV/c(2) is observed in the pi(+/-)psi(2S) intermediate state in the Y(4360) decays.