$2-$Killing Vector Fields on Warped Product Manifolds
  The present article provides a study of $2-$Killing vector fields on warped product manifolds as well as characterization of this structure on standard static and generalized Robertson-Walker space-times. Some conditions for a $2-$Killing vector field on a warped product manifold to be parallel are obtained. Moreover, some results on the curvature of a warped product manifolds in terms of $2-$Killing vector fields are derived. Finally, we apply our results to describe $2-$Killing vector fields of some well known warped product space-time models. 
Sameh Shenawy and Bulent Unal
math.DG