2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/104570In this paper, we study the nucleon energy spectrum in the ground-state (with orbital momentum L=0) and the first excited state (L=1). The aim of this study is to find the mass and mixing angles of excited nucleons using a potential model describing QCD. This potential is of the "Coulombian + linear" type and we take into account some relativistic effects, namely we use essentially a relativistic kinematic necessary for studying light flavors. By this model, we found the proton and $Δ(1232)$ masses respectively equal to ($968MeV$, $1168MeV$), and the masses of the excited states are between $1564MeV$ and $1607MeV$.26 pages, 1 figureHigh Energy Physics - Phenomenologytext