Dependence of deuteron vector-polarization on ion source transition configurations

The deuteron vector polarization of extracted SATURNE II beam as a function of different ion source configurations was studied. In all measurements deuterons were considered as weakly bound protons and neutrons and quasielastic pp→pp+n reaction with the n as a spectator was measured. The Left–Right instrumental asymmetry of the beam polarimeter arms was determined using an unpolarized beam from the ion source Amalthée. The obtained correction factor was applied to asymmetries measured with the beam from the polarized ion source Hyperion in the vector-polarization states. The measurements were carried out at the deuteron beam kinetic energy of 0.80 GeV/nucleon, where the pp-elastic scattering analyzing power is near its maximum. The results showed that in the nominal conditions of the ion source the two so-called ‘unpolarized states’ were differently polarized, whereas the absolute values of the beam polarizations in the so-called ‘polarized states’ were approximately equal and opposite within errors. It was confirmed that the hexapole lens of the ion source produced beam polarization in the absence of any transition. A decrease of the hexapole current provides an extrema for the beam polarizations in the two ‘unpolarized’ states at different current values and slightly violates the equilibrium of polarizations for the ion source polarized states.