Rotated branes and N=1 duality

We consider configurations of rotated NS-branes leading to a family of four-dimensional N = 1 super-QCD theories, interpolating between four-dimensional analogues of the Hanany-Witten vacua, and the Elitzur-Giveon-Kutasov configuration for N = 1 duality. The rotation angle is the N = 2 breaking parameter, the mass of the adjoint scalar in the N = 2 vector multiplet. We add some comments on the relevance of these configurations as possible stringy proofs of N = 1 duality. (C) 1997 Elsevier Science B.V.