The spectroscopy is done by analyzing the different displacements by a magnet. For equal charge, these displacements depend only on velocity, thus for the EI 50's constant kinetic energy conditions, these displacements are uniquely determined by a particle's mass.
Spectroscopy involves assessing different magnetic shifts. When charges are equivalent, these shifts are exclusively influenced by velocity, meaning that for EI 50's fixed kinetic energy scenarios, these shifts are precisely defined by a particle's mass.