The time required for the detector output to go from the initial value to a percentage
(e.g. 99%) of the final value. In the case of an exponential behaviour of the detector

can be related to the
time constant
.
The rise time

is the time required for the detector output to vary between given percentages (e.g.
from 10% to 90%) of the final value. Similarly,
the
fall time
is the time required for the detector output to vary between given percentages (e.g.
from 90% to 10%) of the initial value.
Source:
PAC, 1995, 67, 1745
(Nomenclature, symbols, units and their usage in spectrochemical analysis-XI. Detection
of radiation (IUPAC Recommendations 1995))
on page 1751
Cite as:
IUPAC. Compendium of Chemical Terminology, 2nd ed. (the "Gold Book"). Compiled by
A. D. McNaught and A. Wilkinson. Blackwell Scientific Publications, Oxford (1997).
XML on-line corrected version: http://goldbook.iupac.org (2006-) created by M. Nic,
J. Jirat, B. Kosata; updates compiled by A. Jenkins. ISBN 0-9678550-9-8.
https://doi.org/10.1351/goldbook.