Polarization In P He3 Scattering Between 10 And 20 Mev PDF Download

Proton polarizations were measured for the B10 (He3,p)C12 (4.43 MeV) reaction at He3 energies of 2.5 and 2.8 MeV. These measurements were made for twelve angles from 0 to 135 degrees at 2.5 MeV and for six angles from 15 to 75 degrees at 2.8 MeV. The measurements at 2.5 MeV show that the polarization reaches a minimum of -.36=.07 at theta sub lab=15 degrees where the sign of the polarization follows the Basel Convention. At larger angles the polarization fluctuates and generally decreases. It was not able to be determined whether the polarization changes sign or is zero at the back-angles. The angular dependence of the polarizations at 2.8 MeV are similar to those obtained at 2.5 MeV indicating a weak energy dependence in the energy range used. The polarizations were analyzed by scattering the protons from a plastic scintillator, using the known properties of the polarization of protons scattered by carbon. With the plastic scintillator, it was possible to reduce the backgrounds in the side detectors. This was done by identifying the scattered protons as coincidences between the 2nd scatterer and pulses of the proper energy in the side detectors. Geometrical errors obtained by machine calculations are included in the statistical errors. (Author).