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Onset of asymptotic scaling in deuteron photodisintegration

P. Rossi
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Abstract

We investigate the transition from the nucleon-meson to quark-gluon description of the strong interaction using the photon energy dependence of the $d(γ,p)n$ differential cross section for photon energies above 0.5 GeV and center-of-mass proton angles between $30^{\circ}$ and $150^{\circ}$. A possible signature for this transition is the onset of cross section $s^{-11}$ scaling with the total energy squared, $s$, at some proton transverse momentum, $P_T$. The results show that the scaling has been reached for proton transverse momentum above about 1.1 GeV/c. This may indicate that the quark-gluon regime is reached above this momentum.

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P. Rossi. 2004-12-17. Onset of asymptotic scaling in deuteron photodisintegration. https://doi.org/10.1103/physrevlett.94.012301

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