User stories for HELAS (future milestones)

Short name	Rating	Who	Description
higher dimensions		?	In the NLO method by Kunszt et al. the rational parts are obtained by doing calculations in higher number of integer dimensions. We would need the corresponding HELAS routines to do this. It might be doable once we will be able to write the routines from FeynRules and use some symbolic notation. At that point, at least for the Dirac Algebra it would be enough to have new objects.
complex momenta	*	Valentin	In all NLO unitary based methods amplitudes need to be calculated with two external complex momenta.

User stories for MadEvent (future milestones)

Short name	Rating	Who	Description
SDEMI with recursion	*	?	Think about how to implement Single diagram enhanced multichannel integration when we have recursive calculation of the matrix elements. Johan: Simplified Helas routines? Fabio: Use color structure to make a factorization of the full amplitudes in dual subamplitudes which are gauge invariant and have much simpler propagator structures.

Integration optimization idea

1. better computation of the min/max associated to each variable of integration.
   1. Tim idea: add one iteration with not matrix-element computation just cut
   2. Olivier idea: use python to determine such value
2. allow multiple change of variable for the same Feynman Diagram and use standard technique
   • What about using a NN to learn here?