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arXiv · hep-ex/9811011

Observation of a Coherence Length Effect in Exclusive Rho^0 Electroproduction

K. Ackerstaff
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Abstract

Exclusive incoherent electroproduction of the rho^0(770) meson from 1H, 2H, 3He, and 14N targets has been studied by the HERMES experiment at squared four-momentum transfer Q**2>0.4 GeV**2 and positron energy loss nu from 9 to 20 GeV. The ratio of the 14N to 1H cross sections per nucleon, known as the nuclear transparency, was found to decrease with increasing coherence length of quark-antiquark fluctuations of the virtual photon. The data provide clear evidence of the interaction of the quark- antiquark fluctuations with the nuclear medium.

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K. Ackerstaff. 1998-11-06. Observation of a Coherence Length Effect in Exclusive Rho^0 Electroproduction. https://doi.org/10.1103/physrevlett.82.3025

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