A numerical approach to bifurcations from quadratic centers (Q1922982)

A combination of analytical and numerical work is done to analyze bifurcation of limit cycles form non-Hamiltonian codimension-three quadratic centers. This paper focusses primarily on a numerical study of the integrals which determine the number of limit cycles which persist from the period annuli. The first goal of this paper is to show how the integrals can be used to determine the bifurcation diagram after perturbation and the second is to investigate numerically whether it is possible to create more than four limit cycles within the class of quadratic systems from the center case under consideration.