Grobner Shirshov Basis of the Universal Enveloping Rota-Baxter Algebra of a Lie Algebra

We consider Lie algebras equipped with a Rota Baxter operator. The forgetful functor from this category to the category of Lie algebras has a left adjoint one denoted by U-RB. We prove an operator analogue of the Poincare-Birkhoff-Witt theorem for U-RB by means of Grobner-Shirshov bases theory for Lie algebras with an additional operator.