We report the first evidence for X(3872) production in two-photon interactions by tagging either the electron or the positron in the final state, exploring the highly virtual photon region. The search is performed in e+e-→e+e-J/ψ π+ π-, using 825 fb-1 of data collected by the Belle detector operated at the KEKB e+e-collider. We observe three X(3872) candidates, where the expected background is 0.11±0.10 events, with a significance of 3.2σ. We obtain an estimated value for γB(X(3872)→J/ψ π+ π-) assuming the Q2 dependence predicted by a cc meson model, where-Q2 is the invariant mass squared of the virtual photon. No X(3915)→J/ψ π+ π-candidates are found.
Evidence for X (3872) →j/ψ π+ π-Produced in Single-Tag Two-Photon Interactions / Belle, Collaboration; Campajola, M.; De Nardo, G.; Di Capua, F.; Merola, M.; Pardi, S.; Russo, G.; Et, Al.. - In: PHYSICAL REVIEW LETTERS. - ISSN 0031-9007. - 126:12(2021). [10.1103/PhysRevLett.126.122001]
Evidence for X (3872) →j/ψ π+ π-Produced in Single-Tag Two-Photon Interactions
Campajola M.;De Nardo G.;Di Capua F.;Merola M.;Pardi S.;Russo G.;
2021
Abstract
We report the first evidence for X(3872) production in two-photon interactions by tagging either the electron or the positron in the final state, exploring the highly virtual photon region. The search is performed in e+e-→e+e-J/ψ π+ π-, using 825 fb-1 of data collected by the Belle detector operated at the KEKB e+e-collider. We observe three X(3872) candidates, where the expected background is 0.11±0.10 events, with a significance of 3.2σ. We obtain an estimated value for γB(X(3872)→J/ψ π+ π-) assuming the Q2 dependence predicted by a cc meson model, where-Q2 is the invariant mass squared of the virtual photon. No X(3915)→J/ψ π+ π-candidates are found.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
