snorer.KallenLambda¶
snorer.KallenLambda(x,y,z)¶
Källen lambda function $$ \lambda(x,y,z)=x^2+y^2+z^2-2(xy+yz+zx), $$ a useful function for evaluating kinetical quantities in particle physics.
Parameters:
x
: array_like
y
: array_like
z
: array_like
Returns:
out
: scalar/ndarray
out
is scalar if all inputs are scalars.
References¶
V. Ilisie, Concepts in quantum field theory: A practitioner's toolkit, Springer (2016)