$LimitTo4IRUnsafe is a global variable that determines whether the simplifications described in $LimitTo4 are applied also to C and D Passarino-Veltman functions. In this case it is assumed that such functions are either IR finite, or the IR divergences are regulated without using dimensional regularization (i.e. by introducing fictitious masses). Otherwise the results will be inconsistent. If this option is activated, it is the task of the user to ensure that IR divergences are properly regulated, such that no mixing of \varepsilon from IR and UV can occur. The default value is False.
Overview, PaVe, PaVeReduce, OneLoop, $LimitTo4, PaVeLimitTo4.
$LimitTo4IRUnsafe\text{False}