[Zurück]

L Raffelt, P Lennert, H. Abele, T. Soldner, U. Schmidt, H. Saul, C. Roick, B. Märkisch:
"Preparing a Proton Asymmetry Measurement with PERKEO III";
Vortrag: DPG Spring Meeting Frankfurt 2014, Frankfurt; 17.03.2014 - 21.03.2014.

Precision measurements of angular correlation coefficients in neutron beta decay allow tests of the Standard Model and a determination of the ratio of coupling constants λ = gA / gV of the weak interaction.
We plan to measure the proton asymmetry C with the instrument PERKEO III at the ILL (Grenoble) in 2014. This will provide a crosscheck of other measurements of several neutron decay correlation coefficients and might be sensitive to contributions of scalar and tensor interactions. Currently the only precision measurement of the proton asymmetry has been performed in 2008 with PERKEO II. Using the new spectrometer in pulsed mode and utilizing the improved detector concept, we expect to increase the precision to approximately 0.25%.
Electrons and protons from the decay will be measured in a combined detector. The protons are converted to secondary electrons using a new high voltage system with thin foils. A scintillator with new lightguides and all-side readout will provide a homogeneous detection of the electrons.