| Abstract: | Single hadron azimuthal asymmetries in the cross sections of positive and
negative hadron production in muon semi-inclusive deep inelastic scattering off
longitudinally polarised deuterons are determined using the 2006 COMPASS data
and also all deuteron COMPASS data. For each hadron charge, the dependence of
the azimuthal asymmetry on the hadron azimuthal angle $phi$ is obtained by
means of a five-parameter fitting function that besides a $phi$-independent
term includes four modulations predicted by theory: $sinphi$, $sin 2 phi$,
$sin 3phi$ and $cosphi$. The amplitudes of the five terms have been first
extracted for the data integrated over all kinematic variables. In further
fits, the $phi$-dependence is determined as a function of one of three
kinematic variables (Bjorken-$x$, fractional energy of virtual photon taken by
the outgoing hadron and hadron transverse momentum), while disregarding the
other two. Except the $phi$-independent term, all the modulation amplitudes
are very small, and no clear kinematic dependence could be observed within
experimental uncertainties. |
REGISTER
Did you like this article? 
