Analysis of experimental uncertainties in the R-correlation measurement in the decay of free neutrons

AbstractThe experiment aiming at the simultaneous determination of the two trans-versal polarisation components of electrons emitted in the decay of free, po-larised neutrons is in progress at the Paul Scherrer Institute (Villigen, Switzer-land). The non-zero value of R coefficient, proportional to the polarisationcomponent, which is perpendicular to the plane spanned by the spin of thedecaying neutron and the electron momentum, would prove a violation of timereversal symmetry and thus physics beyond the Standard Model. The plannedaccuracy of the measurement is of order 0.005. To reach this value, the system-atic effects in the experiment have to be controlled on a similar level of accuracy.The emphasis of this master’s thesis is put on the search of systematic effectsby the means of dedicated Monte Carlo simulation, based on extended Geant4package. Implementation details are discussed and the new added features aretested. Finally, the β decay asymmetry induced systematic effect, resulting infalse contribution to R-coefficient is recognised and investigated.StreszczenieW Instytucie Paula Scherrera (Villigen, Szwajcaria) prowadzony jest ekspery-ment majacy na celu jednoczesny pomiar obu poprzecznych sk ladowyc