Speaker
Description
In this work, we present the development of an experimental apparatus aimed at testing the violation of CP symmetry in the decay of positronium. The experimental approach involves the detection of photons emitted in this process using the Nossa Caixa gamma spectrometer and the application of a magnetic field to manipulate the Ps states. Two complementary methods will be used to analyze the decay of ortho-positronium (o-Ps): the inversion of the normal to the plane of the decay photons and the inversion of the population of the Ps magnetic substates.
By examining the angular correlation between three (or more) photons emitted in the decay of ortho-positronium immersed in a magnetic field, it will be possible to establish an upper limit for the violation of CP symmetry or, potentially, to detect its existence. The spectrometer used consists of an array of 108 LYSO(Ce) crystals, recently built at the Open Laboratory of Nuclear Physics and Applications (LAFNA), in the Department of Nuclear Physics of the Institute of Physics of USP (DFN/IFUSP). In addition, a new plastic scintillator detector is being developed for the detection of positrons from radioactive sources, allowing measurements in temporal coincidence with gamma rays. Preliminary results of this detector will be presented.
