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Updated: Jun 21, 2026

Isotopic Effect in Double Proton Transfer Process of Porphycene Investigated by Enhanced QM/MM Method
Published on: July 19, 2019
Possibility of deeply bound hadronic molecules from single pion exchange
1Rudolf Peierls Centre for Theoretical Physics, University of Oxford, Oxford, OX1 3NP, United Kingdom. f.close1@physics.ox.ac.uk
Abstract:
Pion exchange in an S wave between hadrons that are themselves in a relative S wave can shift energies by hundreds of MeV. In the case of charmed mesons D, D;{*}, D0, D1, a spectroscopy of quasimolecular states may arise consistent with enigmatic charmonium states observed above 4 GeV in e;{+}e;{-} annihilation. A possible explanation of Y(4260) --> psipipi and Y(4360) --> psi;{'}pipi is found. Searches in DD[over]3pi channels as well as B decays are recommended to test this hypothesis.
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