Abstract
Polarization observables in nuclear reactions with stable beams have provided important
information concerning structural properties of nuclei and reaction mechanisms and hold great
promise in the context of exotic nuclei. We report on the development of a polarized target based
on plastic foils of 20–200 μm thickness to be used with radioactive ion beams. The operation of
such a target requires a moderately high magnetic field and very low temperatures. The plastic foil
is placed inside a chamber attached to the mixing chamber of a 3He–4He dilution refrigerator.
Cooling of the foil is achieved via a superfluid film of 4He that can be supplied through two
capillaries. The chamber has two thin, highly uniform silicon nitride windows. An NMR coil is
attached to the target to monitor the polarization. Results of a first test to characterize the target
system, using the elastic scattering of 38 MeV 12C by protons in inverse kinematics are presented.
