Eur. Phys. J. A (2007) 32: 489-495
https://doi.org/10.1140/epja/i2006-10422-0

PAVI 2006

Beam normal spin asymmetries: Theory

¹ Department of Physics, College of William and Mary, 23187, Williamsburg, VA, USA
² Thomas Jefferson National Accelerator Facility, 23606, Newport News, VA, USA

^* e-mail: marcvdh@jlab.org

Received: 31 August 2006
Accepted: 18 March 2007
Published online: 3 July 2007

Abstract

The beam normal spin asymmetry in elastic electron-nucleon scattering is discussed. This beam normal spin asymmetry depends on the imaginary part of two-photon exchange processes between electron and nucleon, and measures the non-forward structure functions of the nucleon. After briefly reviewing the theoretical formalism, we discuss calculations in the threshold region, in the resonance region, as well as in the diffractive region, corresponding with high energy and forward angles.