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تسجيل مستخدم جديدDetermination of the Gluonic D-term and Mechanical Radii of Proton from Experimental data
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We apply a color tripole ansatz for describing the $D$-term of the proton. By fitting the experimental data of the vector meson J/$psi$ and $phi$ photoproductions near the thresholds, we firstly obtained the gluonic $D$-term of the proton. $D_g(0)$ is estimated to be $-2.16pm0.42$ for J/$psi$ and $-1.31pm0.48$ for $phi$, and the mechanical root mean square radius of proton is estimated to be $0.61pm0.29$ fm for $phi$ and $0.42pm0.11$ fm for J/$psi$.
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