Optics and Materials Group – OPTMA, Universidade Federal de Alagoas, Caixa Postal 2051,

We obtain a well-defined topological charge signature from the intensity correlation of two spatially incoherent Laguerre-Gauss beams of differing orders when each beam is diffracted by a triangle. We show that the value of the obtained topological charge follows a correlation rule such that its value is related to the topological charges associated to both incoherent beams. This paper suggests a way to measure an effective topological charge of the coherence function, and opens a new window for studies of correlation between different orders of optical vortex beams