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Manuscript Title: SUSYCAL: symbolic computations in supersymmetric theories.
Authors: T. Kreuzberger, W. Kummer, M. Schweda
Program title: SUSYCAL
Catalogue identifier: ABLW_v1_0
Distribution format: gz
Journal reference: Comput. Phys. Commun. 58(1990)89
Programming language: Pascal.
Computer: CDC CYBER 170-860.
Operating system: NOS/VE 1.3.1.
RAM: 122K words
Word size: 64
Keywords: Supersymmetry, Non-covariant gauges, Symbolic manipulation Of formulae, Computer algebra, Particle physics, Elementary, Qcd.
Classification: 5, 11.5.

Nature of problem:
Non-covariant gauges within the superfield formalism have several advantages over the covariant formulation. One of the most famous examples is the Wess-Zumino gauge where the dimensionless field is eliminated by the equations of motion. The algebra of covariant derivates is extended through the introduction of explicit Grassmann variables. This leads in most cases to much more complicated propagators. Using the Feynman rules to evaluate even simple graphs the integrations in superspace becomes extremely tedious. It is therefore necessary to use automatized means in order to be able to calculate e.g. self-energies.

Solution method:
SUSYCAL contains a set of procedures which can evalute algebraic expressions. For each step in the computation of a graph (e.g. integrations in superspace, simplification using commutation rules) there is a procedure performing it just in the same way as one might do it by manual calculation. Therefore a complete computation can be translated into a series of calls to SUSYCAL procedures. All necessary (anti)commutation rules, rules for Pauli matrices and even integrations in superspace and divergent parts of integrals over momenta are included in SUSYCAL. Restrictions: Only a limited set of non-covariant integrals is included in SUSYCAL. This set is intended for evaluation of self-energies at the one-loop level. Extensions are very difficult to implement. Anyhow, for computations beyond the one-loop level one has to be careful about the regularization scheme.

Unusual features:
The main program must be supplied by the user and is only then compiled together with the procedures contained in the SUSYCAL package.

Running time:
The running time depends strongly on the kind of problem to be solved. For the example in the test deck it took 0.8s CPU-time to compute the self-energy and evaluate the integrals. In this and other simple cases the CPU-time requirements are dominated by the compilation time.