THE NON-RELATIVISTIC APPROXIMATION IN THE THEORY OF SPIN ½ PARTICLE WITH THREE ADDITIONAL CHARACTERISTICS IN PRESENCE OF ELECTROMAGNETIC FIELDS, НЕРЕЛЯТИВИСТСКОЕ ПРИБЛИЖЕНИЕ В ТЕОРИИ ЧАСТИЦЫ СО СПИНОМ ½ И ТРЕМЯ ДОПОЛНИТЕЛЬНЫМИ ХАРАКТЕРИСТИКАМИ В ПРИСУТСТВИИ ЭЛЕКТРОМАГНИТНЫХ ПОЛЕЙ

<jats:p>We start with the well-known Dirac-type four-component equation for a spin ½ particle with three additional characteristics, which includes several interaction terms interpreted as related to certain additional electromagnetic characteristics of a spin ½ particle. In this paper, we investigate the nonrelativistic approximation for this theory in the presence of electromagnetic fields. It turns out that in the nonrelativistic approximation, the derived equation takes the form of the standard Pauli-like equation for a spin ½ particle with an anomalous magnetic moment, defined as the sum of three parameters \((\mu+\sigma +\eta)\) interpreted differently in the relativistic case.</jats:p>