Energy Relaxtation and Hot Spot Formation in Superconducting Single Photon Detectors SSPDS I.N. Florya, Yu. P. Korneeva, M.V. Sidorova, A.D. Golikov, I.A. Gaiduchenko, G.E. Fedorov, A.A. Korneev, B.M. Voronov and G.N. Goltsman EPJ Web of Conferences, 103 (2015) 10004 Published online: 25 September 2015 DOI: 10.1051/epjconf/201510310004