Electron scattering experiments with polarized hydrogen/deuterium internal targets

Abstract

A high-density polarized hydrogen/deuterium internal gas target is presented. The target is based on a setup previously used in electron scattering experiments with tensor-polarized deuterium [1]. To increase the target thickness, new state-of-the-art permanent sextupole magnets and a more powerful pumping system were installed together with a longer (60 cm) and colder (∼70 K) cylindrical storage cell. Electro-nuclear spin observables were measured by scattering longitudinally polarized electrons stored in the AmPS ring (NIKHEF) from the target gas. The product of electron beam and target polarization was determined from the known e′p (quasi) elastic asymmetries. We achieved a target thickness of 1.1×1014 atoms/cm2 which with typical beam currents of 110 mA corresponds to a luminosity of about 7.5×1031 cm−2 s−1. Target and beam polarizations up to 0.7 and 0.65 respectively were obtained.