Nuclear Transparency in Exclusive p° Production at HERMES
نویسنده
چکیده
Exclusive coherent and incoherent electroproduction of the p° meson from H and N targets has been studied at the HERMES experiment as a function of coherence length (lc), corresponding to the lifetime of hadronic fluctuations of the virtual photon, and squared fourmomentum of the virtual photon (—<2). The ratio of N to *H cross sections per nucleon, called nuclear transparency, was found to increase (decrease) with increasing coherence length for coherent (incoherent) p° electroproduction. For fixed coherence length, arise of nuclear transparency with Q is observed for both coherent and incoherent p° production, which is in agreement with theoretical calculations of color transparency.
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