From on-shell to off-shell open gauge theories

We present an alternative quantization for irreducible open gauge theories. The method relies on the possibility of modifying the classical Becchi-Rouet-Stora-Tyutin (BRST) operator and the gauge-fixing action written as in Yang-Mills type theories in order to obtain an on-shell invariant quantum action by using equations characterizing the full gauge algebra. From this then follows the construction of an off-shell version of the theory. We show how it is possible to build off-shell BRST algebra together with an invariant extension of the classical action. This is realized via a systematic prescription for the introduction of auxiliary fields