The single-particle spectrum is a distribution of a physical quantity such as
energy
In physics, energy (from Ancient Greek: ἐνέργεια, ''enérgeia'', “activity”) is the quantitative property that is transferred to a body or to a physical system, recognizable in the performance of work and in the form of hea ...
or
momentum. The study of particle spectra allows us to see the global picture of particle production.
The spectrum are particles that are in space. This belongs to
Raman spectroscopy by
Chandrasekhar Venkata Raman. Spectrum particles are nothing but the
VIBGYOR rays which are separated by prism or water. For example, a rainbow.
Physical quantities
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