Renormalons in exclusive meson electroproduction
نویسنده
چکیده
We discuss the possibility of measuring generalized parton distributions in exclusive electroproduction of mesons off the nucleon and estimate the uncertainty from perturbatively induced higher-twist corrections. We find that, while the magnitude of the cross section changes significantly taking into account twist-four contributions modeled via renormalons, the transverse spin asymmetry is weakly sensitive to them and displays the precocious scaling. An extraction from talks given at CIPANP 2003 (New York City, May 2003) Symposium “A celebration of JLab physics" (Jefferson Lab, June 2003) Annual meeting of American Physical Society (Philadelphia, April 2003) Renormalons in exclusive meson electroproduction
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