| Thème(s) : |
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Physique/Physique des Hautes Energies - Expérience
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| Titre : |
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Study of X(3915) --> J/\psi \omega\ in two-photon collisions |
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| Auteur : |
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J. P. Lees1, V. Poireau1, V. Tisserand1, D. Bernard2, M. Verderi2, S. Emery3, G. Hamel de Monchenault3, G. Vasseur3, Ch. Yèche3, N. Arnaud4, M. Davier4, D. Derkach4, G. Grosdidier4, F. Le Diberder4, A. M. Lutz4, B. Malaescu4, P. Roudeau4, M. H. Schune4, A. Stocchi4, G. Wormser4, S. Akar5, E. Ben-Haim5, M. Bomben5, G.R. Bonneaud5, H. Briand5, G. Calderini5, J. Chauvau5, O. Hamon5, Ph. Leruste5, G. Marchiori5, J. Ocariz5, S. Sitt5 |
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| Laboratoire : |
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| Résumé : |
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We study the process $\gamma \gamma \to J/\psi \omega$ using a data sample of 519.2 $fb^{-1}$ recorded by the BaBar detector at SLAC at the PEP-II asymmetric-energy $e^+ e^-$ collider at center-of-mass energies near the $\Upsilon(nS)$ ($n = 2,3,4$) resonances. We confirm the existence of the charmonium-like resonance X(3915) decaying to $J/\psi \omega$ with a significance of 7.6 standard deviations, including systematic uncertainties, and measure its mass $(3919.4 \pm 2.2 \pm 1.6) MeV/c^2$ and width $(13 \pm 6 \pm 3) MeV$, where the first uncertainty is statistical and the second systematic. A spin-parity analysis supports the assignment $J^P=0^+$ and therefore the ident ification of the signal as due to the $\chi_{c0}(2P)$ resonance. In this hypothesis we determine the product between the two-photon width and the final state branching fraction to be $(52 \pm 10 \pm 3) eV$ |
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| Collaboration/Projet : |
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BABAR |
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| Type de publication : |
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Articles dans des revues avec comité de lecture |
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Date de publication ou d'écriture : |
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2012 |
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| Nom du périodique : |
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| Physical Review D (Phys. Rev. D) |
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American Physical Society |
| ISSN |
1550-7998 (eISSN : 1550-2368) |
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| Volume : |
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86 |
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| Page/Article : |
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072002 |
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| Identifiant local : |
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BABAR-PUB-12/001, SLAC-PUB-15179 |
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| Commentaire : |
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12 pages, 8 postscript figures, submitted to Physical Review D - See paper for full list of authors |
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