Large N Limit of Higher Derivative Extended CP(N) Model
  We construct a fourth-order derivative CP(N) model in 1+1 dimensions by incorporating the topological charge density squared term into the Lagrangian. We quantize the theory by reformulating with auxiliary fields and then performing the path integral explicitly. We discuss the renormalizability in the large N limit and relevance of the effective action with axion physics. 
Taichi Itoh (Kyungpook National University), Phillial Oh (Sungkyunkwan   University)