A term applied to a pulsed @[email protected], meaning that the @[email protected] emission lasts as long as the pumping process is sufficient to sustain @[email protected] conditions. Typical pulse durations are in the \(\unicode[Times]{x3BC}\text{s}\)-\(\text{ms}\) range, depending on the pumping source. When the operation @[email protected] of a pulsed @[email protected] is not specified as @[email protected], Q-switched, or anything else, it must be considered as free-running.