noun
: an arrangement of particle energies (as of alpha particles or photoelectrons) in a heterogeneous beam that is analogous to the arrangement of frequencies in an optical spectrum
noun
: an arrangement of particle energies (as of alpha particles or photoelectrons) in a heterogeneous beam that is analogous to the arrangement of frequencies in an optical spectrum
Webster's New International English Dictionary. Новый международный словарь английского языка Webster. 2012