Speaker
Description
$J/\psi$ photo-production near threshold provides a unique window into the non-perturbative structure of the gluonic fields of the nucleon, enabling access to information regarding the origin of its mass and mass radius. In the Jefferson Lab E12-16-007 experiment, we measured the two-dimensional $J/\psi$ photo-production cross-section as a function of photon energy $E_{\gamma}$ and momentum transfer $t$ near-threshold. The E12-16-007 experiment was conducted in the experimental Hall C using a high-intensity bremsstrahlung photon beam generated by a 10.6 GeV incident electron beam traversing a copper radiator upstream of a liquid hydrogen target. We will present new results on the two-dimensional $J/\psi$ photo-production cross-section measurement in photon energy $E_{\gamma}$ and $t$, and their impact on our knowledge of the proton mass radius and the relative quantum anomalous energy contribution to its mass.
| speaker affiliation | University of Tennessee |
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