Abstract
The quark structure of the meson has, for many years, been assumed to be a pure quark-antiquark () resonance with quantum numbers . Recently, it was proposed that the is a molecular state made from the attractive interaction of two mesons. Such a state would be expected to decay strongly to final states with charged pions due to the dominant decay , whereas decay to two neutral pions would likely be suppressed. Here, we measure for the first time the reaction , using the CEBAF Large Acceptance Spectrometer detector at Jefferson Lab for incident beam energies between 3.6 and 5.4 GeV. Differential cross sections, , for photoproduction are extracted with good precision due to low backgrounds and are compared to theoretical calculations.
- Received 29 October 2020
- Revised 8 January 2021
- Accepted 4 February 2021
DOI:https://doi.org/10.1103/PhysRevLett.126.082002
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