Photon Splitting and Photon-plasmon Interaction in a Dense Medium

The photon splitting is the process with minimal rank of nonlinearity in the electromagnetic interactions. This kind of reaction is to be realized in various astrophysical objects (white dwarves, neutron stars), the early Universe and in the heavy ion collision experiments. In all these cases Furry’s theorem is violated because of the presence of the environments such as external fields or dense media. The photon splitting due to a magnetic field has been rather intensively investigated by many authors [1]. This process was also considered in the rest plasma [2] and the uniformly moving medium [3]. In the latter article the three-photon vertex has been calculated in one-loop approximation for the most general case but the final expressions represented in terms of complicate integrals, that makes difficult the detailed analysis of the corresponding amplitude. Besides, there were some calculation peculiarities that have not been taken [email protected] [email protected]