dynamic spectrum

https://doi.org/10.1351/goldbook.08590
Spectrum of a material under the influence of an applied external perturbation represented by a variable τ, relative to a reference spectrum.
Note:
The reference spectrum may be chosen in many ways; e.g., it may be the average over τ, of the observed spectrum, or it may be zero.
Source:
PAC, 2021, 93, 647. (Glossary of methods and terms used in analytical spectroscopy (IUPAC Recommendations 2019)) on page 744 [Terms] [Paper]