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arXiv · hep-ex/9808028

Measurements of R=sigma_L/sigma_T for 0.03<x<0.1 and Fit to World Data

E143 collaboration
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Abstract

Measurements were made at SLAC of the cross section for scattering 29 GeV electrons from carbon at a laboratory angle of 4.5 degrees, corresponding to 0.03<x<0.1 and 1.3<Q^2<2.7 GeV^2. Values of R=sigma_L/sigma_T were extracted in this kinematic range by comparing these data to cross sections measured at a higher beam energy by the NMC collaboration. The results are in reasonable agreement with pQCD calculations and with extrapolations of the R1990 parameterization of previous data. A new fit is made including these data and other recent results.

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E143 collaboration. 1998-08-26. Measurements of R=sigma_L/sigma_T for 0.03<x<0.1 and Fit to World Data. https://doi.org/10.1016/s0370-2693(99)00244-0

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