# Beam-spin Asymmetries from Semi-inclusive Pion Electroproduction

Abstract : We have measured the moment $A_{LU}^{\sin\phi}$ corresponding to the polarized electron beam-spin asymmetry in SIDIS. $A_{LU}^{\sin\phi}$ is a twist-3 quantity providing information about quark-gluon correlations. Data were taken with the CLAS Spectrometer at Jefferson Lab using a 5.498 GeV longitudinally polarized electron beam and an unpolarized liquid hydrogen target. All three pion channels ($\pi^+$, $\pi^0$ and $\pi^-$) were measured simultaneously over a large range of kinematics within the virtuality range $Q^2 \approx$ 1.0-4.5 GeV$^2$. The observable was measured with good statistical precision over a large range of $z$, $P_T$, $x_B$, and $Q^{2}$, which permits comparison with several reaction models. The discussed measurements provide an upgrade in statistics over previous measurements, and serve as the first evidence for the negative sign of the $\pi^{-}$ $\sin\phi$ moment.
Document type :
Journal articles
Domain :

http://hal.in2p3.fr/in2p3-00948265
Contributor : Emmanuelle Vernay <>
Submitted on : Tuesday, February 18, 2014 - 8:40:08 AM
Last modification on : Thursday, November 19, 2020 - 12:59:05 PM

### Citation

W. Gohn, E. Voutier, J. Ball, Gabriel Charles, M. Garcon, et al.. Beam-spin Asymmetries from Semi-inclusive Pion Electroproduction. Physical Review D, American Physical Society, 2014, 89, pp.072011. ⟨10.1103/PhysRevD.89.072011⟩. ⟨in2p3-00948265⟩

Record views