Rare top decay $t\rightarrow c\gamma$ in general THDM-III
  We study the decay $t\rightarrow c\gamma$ with flavor-changing neutral interactions in scalar sector of the type III Two Higgs Doublet Model (THDM-III) with mixing between neutral scalar fields as a result of considering the most general scalar potential. The branching ratio of the decay $Br(t\rightarrow c\gamma)$ is calculated as function of the mixing parameters and masses of the neutral scalar fields. We obtain a $Br(t\rightarrow c\gamma)$ of the order of $10^{-8}$ for the considered regions of the mixing parameters. Finally, one upper bound for the possible events is estimated to be $n=18$ by assuming a expected luminosity of the order of 300 $fb^{-1}$. 
R. Gaitan-Lozano, R. Martinez, J.H. Montes de Oca
hep-ph