Measuring the tensor polarization of positronium

A method for measuring the tensor polarization in a positronium (Ps) beam is proposed, which is based on the determination of the Ps lifetime as a function of the orientation of a homogeneous magnetic field. The dependence of the orthopositronum (o-Ps) lifetime on the angle between the directions of the magnetic field and the tensor polarization of the Ps beam can be determined from the results of measurements from two or more field orientations.