1 MeV electron irradiation has been performed in degenerate,n‐type (n&bartil;2×1017cm−3), molecular beam epitaxial GaAs layers, and Hall effect measurements have been carried out during the irradiation in order to get accurate defect production data. The results have been fitted with statistical models, and are most consistent with the usualE1 (EC−0.045 eV) andE2 (EC−0.15 eV) levels being the (−/0) and (0/+) transitions of the As vacancy, respectively. Also, an acceptor well belowEC−0.15 eV is produced at a much higher rate than that ofE1 andE2.