Name: Pablo Sanchez Puertas (email_not_shown)
Date: 01/26/17-02:32:11 PM Z


Hello again.

I just reinstalled FeynCalc and is working fine! :D
Thanks for the continuous support with the program!

Besides, but that would probably be a new thread, I
would like to comment on the tensor 5-point function.
(I don't really need it at the moment as I have
alternative ways to deal with it, but could be of interest)
I could notice that your implmentation relying in
Eq. (4.54) from

https://arxiv.org/pdf/0709.1075.pdf

holds (quoting from the article above)

" [...] if the Lorentz decomposition of the appearing
tensor integrals contains only momenta and no metric
tensors, which is the case for N geq. 6 or P = 0."

Particularly, for the 5-point function (N=4), that implies
that such is not generally the case whenever one deals
with a tensor instead of a scalar function.
If such is the case, there are additional terms which are
documented (also from Denner and Dittmaier) in

http://inspirehep.net/record/605032

see the "V(and U) terms" there or Eq.(2.21). The terms
implemented in "NPointto4Point.m" are only those in the
first summation. I could check that, though the notebook I
have is a bit messy. Let me know uf you are interested and
I could try to provide you with a minimal working example
of the isse.

Pablo



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