We have measured the nuclear transparency of the incoherent diffractive A(e, e 'ρ 0) process in 12C and 56Fe targets relative to 2H using a 5 GeV electron beam. The nuclear transparency, the ratio of the produced ρ 0's on a nucleus relative to deuterium, which is sensitive to ρA interaction, was studied as function of the coherence length (l c), a lifetime of the hadronic fluctuation of the virtual photon, and the four-momentum transfer squared (Q 2). While the transparency for both 12C and 56Fe showed no l c dependence, a significant Q 2 dependence was measured, which is consistent with calculations that included the color transparency effects.
|Original language||English (US)|
|Number of pages||5|
|Journal||Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics|
|State||Published - Jun 12 2012|
Bibliographical noteFunding Information:
We thank M. Sargsian for independent evaluation of the Fermi motion effect. We would like to acknowledge the outstanding efforts of the staff of the Accelerator and the Physics Divisions at Jefferson Lab that made this experiment possible. This work was supported in part by the US Department of Energy, Office of Nuclear Physics , under contracts No. DE-AC02-06CH11357 and No. DE-FG02-88ER40410 , the Chilean FONDECYT grants 1080564 and 3100064 CONICYT ACT-119, BASAL FB0821, the National Science Foundation , the Italian Istituto Nazionale di Fisica Nucleare , the French Centre National de la Recherche Scientifique , the French Commissariat à lʼEnergie Atomique , the National Research Foundation of Korea , the UK Science and Technology Facilities Council (STFC) , and the Physics Department at Moscow State University . The Jefferson Science Associates (JSA) operates the Thomas Jefferson National Accelerator Facility for the United States Department of Energy under contract DE-AC05-06OR23177.