Confirmation of a pi_1^0 Exotic Meson in the ηπ^0 System

G. S. Adams; T. Adams; Z. Bar-Yam; J. M. Bishop; V. A. Bodyagin; D. S. Brown; N. M. Cason; M. Chasse; S. U. Chung; J. P. Cummings; A. I. Demianov; K. Danyo; J. P. Dowd; P. Eugenio; X. L. Fan; A. M. Gribushin; R. W. Hackenburg; M. Hayek; J. Hu; E. I. Ivanov; D. Joffe; W. Kern; E. King; O. L. Kodolova; V. L. Korotkikh; M. A. Kostin; J. Krenkel; J. Kuhn; J. M. LoSecco; M. Lu; L. V. Malinina; J. J. Manak; M. Nozar; C. Olchanski; A. I. Ostrovidov; T. K. Pedlar; L. I. Sarycheva; K. K. Seth; N. Shenhav; X. Shen; W. D. Shephard; N. B. Sinev; D. L. Stienike; J. S. Suh; S. A. Taegar; A. Tomaradze; I. N. Vardanyan; D. P. Weygand; D. B. White; H. J. Willutzki; M. Witkowski; A. A. Yershov

doi:10.1016/j.physletb.2007.07.068

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arXiv · hep-ex/0612062

Confirmation of a pi_1^0 Exotic Meson in the ηπ^0 System

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Abstract

The exclusive reaction $π^- p \to ηπ^0 n$, $η\to π^+ π^- π^0$ at 18 GeV$/c$ has been studied with a partial wave analysis on a sample of 23~492 $ηπ^0 n$ events from BNL experiment E852. A mass-dependent fit is consistent with a resonant hypothesis for the $P_+$ wave, thus providing evidence for a neutral exotic meson with $J^{PC} = 1^{-+}$, a mass of $1257 \pm 20 \pm 25$ MeV$/c^2$, and a width of $354 \pm 64 \pm 60$ MeV$/c^2$. New interpretations of the meson exotics in neutral $ηπ^0$ system observed in E852 and Crystal Barrel experiments are discussed.

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G. S. Adams, T. Adams, Z. Bar-Yam, J. M. Bishop, V. A. Bodyagin, D. S. Brown, N. M. Cason, M. Chasse, S. U. Chung, J. P. Cummings, A. I. Demianov, K. Danyo, J. P. Dowd, P. Eugenio, X. L. Fan, A. M. Gribushin, R. W. Hackenburg, M. Hayek, J. Hu, E. I. Ivanov, D. Joffe, W. Kern, E. King, O. L. Kodolova, V. L. Korotkikh, M. A. Kostin, J. Krenkel, J. Kuhn, J. M. LoSecco, M. Lu, L. V. Malinina, J. J. Manak, M. Nozar, C. Olchanski, A. I. Ostrovidov, T. K. Pedlar, L. I. Sarycheva, K. K. Seth, N. Shenhav, X. Shen, W. D. Shephard, N. B. Sinev, D. L. Stienike, J. S. Suh, S. A. Taegar, A. Tomaradze, I. N. Vardanyan, D. P. Weygand, D. B. White, H. J. Willutzki, M. Witkowski, A. A. Yershov. 2007-07-11. Confirmation of a pi_1^0 Exotic Meson in the ηπ^0 System. https://doi.org/10.1016/j.physletb.2007.07.068

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