LIFE_TIME (unit days)

Syntax:

LIFE_TIME eeeee

Where eeeee is a number in floating point notation (see examples) that denotes the lifetime in days of the tracer. When a positive number is given, the tracer will decay with the equation T = T0 exp(-t/LIFE_TIME) (with t measured in days). Rn, for instance, has a lifetime of about 5.5 days towards radioactive decay.

A negative number indicates an infinite lifetime (for radioactive decay that is)

Examples:

LIFE_TIME 5.5

LIFE_TIME 3.65E2

Default:

LIFE_TIME -1.0