Eur. Phys. J. A (2007) 32: 501-503
https://doi.org/10.1140/epja/i2006-10423-y

PAVI 2006

Transverse beam asymmetries measured from ⁴He and hydrogen targets

Department of Physics, University of Massachusetts, 01003, Amherst, MA, USA

^* e-mail: lkaufman@jlab.org;

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

Abstract

The HAPPEX Collaboration at Jefferson Lab has measured the transverse beam spin asymmetries (A_T) for elastic electron scattering from proton and ⁴He targets. The experiment was conducted using a vertically polarized electron beam of energy ∼ 3 GeV, at a Q ² ∼ 0.1 GeV^2 and a scattering angle θ_lab ∼ 6^° . The preliminary results are reported here. The ⁴He measurement is the first measurement of A_T from a nucleus. A_T for ⁴He is non-negligible; therefore, it will be necessary to make measurements of A_T for future parity-violating experiments using nuclear targets.