Exploration of trace anomaly contribution to proton mass based on light vector meson photoproduction

Abstract

In the quantum chromodynamics, the mass source of the proton is decomposed into four parts by the energy momentum tensor : quark energy term, gluon energy term, quark mass term and trace anomaly term. And the trace anomaly term is the most crucial contribution for studying the internal structure of the proton. In this work, under the definition of the vector meson dominant model, the trace anomaly contribution of the proton is extracted from the experimental datas of light vector mesons $\rho$, $\omega$ and $\varphi$ photoproduction at the near-threshold, which are ($1.15\pm 0.08$)$\%$, ($2.70\pm 0.04$)$\%$ and ($5.58\pm 0.25$)$\%$, respectively. Eventually, the average trace anomaly contribution of the proton is ($4.36\pm 0.40$) $\%$, which only account for a small fraction of the total proton mass. The result of this work will provide theoretical information support for further study of proton internal structure.

7 pages, 4 figures

References in corpus (8)

• Electron-Ion Collider in China
• The mass radius of the proton
• Revisiting the proton mass decomposition
• $J/\psi$-$p$ Scattering Length from the Total and Differential Photoproduction Cross Sections
• QCD Effective Coupling in the Infrared Region
• Near-threshold photoproduction of $J/\psi$ in two-gluon exchange model
• Extraction of Proton Trace Anomaly Energy from Near-Threshold $\varphi$ and $J/\psi$ photo-productions
• Mass radius and mechanical properties of the proton via strange $\varphi$ meson photoproduction

Cited by in corpus (2)

• Systematic investigation of trace anomaly contribution in nucleon mass
• Analysis of $J/\psi$ and $\psi (2S)$ Charmonium Production in Ultraperipheral Lead-Lead and Proton-Lead Collisions at LHC Energies