When does a right-angled Artin group split over $\mathbb{Z}$?
  We show that a right-angled Artin group, defined by a graph $\Gamma$ that has at least three vertices, does not split over an infinite cyclic subgroup if and only if $\Gamma$ is biconnected. Further, we compute JSJ--decompositions of 1--ended right-angled Artin groups over infinite cyclic subgroups. 
Matt Clay
math.GR