The general type N solution of new massive gravity

We find the most general algebraic type N solution with non-vanishing scalar curvature which comprises all type N solutions of new massive gravity in three dimensions We also give the special forms of this solution which correspond to certain critical values of the topological mass Finally we show that at the special limit the null Killing isometry of the spacetime is restored and the solution describes AdS pp-waves (C) 2010 Elsevier B V All rights reserved