QCDloop: A repository for one-loop scalar integrals
# QCDloop: A repository for one-loop scalar integrals

This is a repository of one-loop scalar Feynman integrals,
evaluated close to four dimensions.
For integrals with all massive internal lines
the integrals are all known, both analytically and numerically.
This website therefore concentrates on integrals with some internal masses
vanishing; in general, these integrals contain infra-red and collinear
singularities which are here regulated dimensionally.
The integrals are described in a PDF file for every known integral.
The general divergent box integral can be calculated using one of sixteen basis
integrals which are given here.
The general divergent triangle integral can be calculated using one of six triangle basis
integrals which are also given here.
The browser must be set to use hypertex-aware tool, such as Acrobat reader,
and for best viewing, should open the pdf files in the browser.
For general notation for the loop integrals
click here

The results in this web-site are also available in the paper arXiv:0712.1851
by R.K. Ellis and G. Zanderighi

The corresponding gfortran/fortran77 code which calculates an arbitrary
one-loop scalar integral, finite or divergent can be
downloaded,

QCDLoop-1.98.tar.gz (version 1.981, date 2021-Apr-30).
If you encounter any problems with the code, please notify the authors.

We gratefully acknowledge comments on previous versions of the
code from

Stefano Actis, Andre van Hameren, Francesco Tramontano, Kirill Melnikov,
Gudrun Heinrich, Jacek Holeczek, Adrian Signer, and Markus Schulze.

Other associated tools for one-loop diagrams:-

Looptools

the FF package by G.J. van Oldenborgh

R. Keith Ellis
Last modified: Thu Feb 25 17:43:23 GMT 2021