Abstract: | The single molecular magnet Fe8 is known to exhibit quantum tunneling of the magnetization. This tunneling can take place from a meta-stable state to an excited state, accompanied by a transition to the ground state. While the tunneling is evident from the magnetization reversal, the transition to the ground state is detected by a temperature rise. This temperature rise can ignite a unique behavior of magnetic relaxation called 'Magnetic Deflagration'. The Fe8 temperature after tunneling can be detected from the deflagration theory or directly. In this work I measured this temperature directly and compared with the deflagration approach. The two methods roughly agree. My measurements suggest how the transition to the ground state can be taken into account when calculating the tunneling probability |