The O(n) Model in the $n\to 0$ Limit (self-avoiding-walks) and   Logarithmic Conformal Field Theory
  We consider the O(n) theory in the $n \to 0$ limit. We show that the theory is described by logarithmic conformal field theory, and that the correlation functions have logarithmic singularities. The explicit forms of the two-, three- and four-point correlation functions of the scaling fields and the corresponding logarithmic partners are derived. 
M. Sadegh Movahed, M. Saadat, M. Reza Rahimi Tabar