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Just in case someone stumbles over this old thread:

Yes, in FeynCalc 9.3 we do have a function to analyze the UV (not IR!!!)

divergences of arbitrary Passarino-Veltman coefficient functions, c.f.

https://feyncalc.org/forum/1287.html

I recommend to use it with the global option

$KeepLogDivergentScalelessIntegrals set to True

Then:

A0[m^2] // PaVeUVPart

-> -((2 m^2)/(-4 + D))

or

B0[SPD[p, p], 0, m^2] // PaVeUVPart

-> -(2/(-4 + D))

Alternatively (or as a cross-check) one could use PaXEvaluateUV /

PaXEvaluateUVIRSplit from the FeynHelpers extension. PaXEvaluateUV uses

Package-X, while PaVeUVPart uses a different algorithm from Georg Sulyok

(https://inspirehep.net/record/727190)

Cheers,

Vladyslav

*> Rolf,
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*>
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*> Thanks for the variation of the notebook. I have two questions:
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*>
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*> 1. Does FeynCalc have functions that allow for the analysis of the two point
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*> integrals A0, B0 etc. in the limit D -> 4+e so that the divergent parts of
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*> the self energies can be extracted and analysed?
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*>
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*> 2. Is it possible to use TARCER to perform the same calculation as done in
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*> my notebook but for two loop diagrams? My attempt to do this is in the
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*> attached file. I have tried applying ToTFI to the results of CreateFCAmp but
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*> very few of the terms correctly reduce to TFI form. I deduce from looking at
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*> the results from ToTFI that the problem lies at least partly in the fact
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*> that ToTFI does not deal with terms with numerators containing odd powers of
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*> the internal loop momenta q1 and q2. Presumably these terms are zero by
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*> symmetric integration. Are there TARCER functions that allow for these terms
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*> to be handled (some sort of analogue of OneLoopSimplify)?
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*>
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*> Many thanks
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*> Jon Palmer
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**Next message:**V. Shtabovenko: "Re: TarcerExpand"**Previous message:**V. Shtabovenko: "Re: a problem about \gamma^0 matrix"**Maybe in reply to:**Jon Palmer: "RE: FeynCalc5 Beta1"**Next in thread:**Rolf Mertig: "Re: FeynCalc5 Beta1"**Messages sorted by:**[ date ] [ thread ] [ subject ] [ author ]**Mail actions:**[ respond to this message ] [ mail a new topic ]

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