Where Can I Find Software for Calculating Tensor Loop Integrals?

Daniel Reyes
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Hi there!

I was wondering if anybody knows what package or software CERN of other particle accelerators use to calculate their theoretical predictions. I need specifically tensor loop integrals of up to rank four and of three and four vertices.

Thanks!
 
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Quite a few high energy physics software projects are hosted at HepForge. Maybe one of those projects will meet your needs.

And Welcome to Physics Forums!
 
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websterling said:
Quite a few high energy physics software projects are hosted at HepForge. Maybe one of those projects will meet your needs.

And Welcome to Physics Forums!

Thanks websterling. I'll check that out!
 
Hello, is there a reason why you want the tensor integrals rather than the reduced scalar integrals?

Typically one always does a reduction to scalar integrals and then uses one of the packages like OneLOop or looptools to solve these numerically. OneLOop is particularly nice since it provides the integrals in dim reg and returns the 1/eps 1/eps^2 pieces and is useable with complex masses. looptools can be easily used with Mathematica.
 
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RGevo said:
Hello, is there a reason why you want the tensor integrals rather than the reduced scalar integrals?

Typically one always does a reduction to scalar integrals and then uses one of the packages like OneLOop or looptools to solve these numerically. OneLOop is particularly nice since it provides the integrals in dim reg and returns the 1/eps 1/eps^2 pieces and is useable with complex masses. looptools can be easily used with Mathematica.

Actually, that's what I need but I have a lot of terms so the reduction by hand is out of the question. Maybe there's a data base where I can find all the coefficients for the reduction so I can implement a program?
 
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