Optical Observation of Spontaneous Heat Burst Phenomena during Hydrogen Desorption from Nano-Sized Metal Composite

We have constructed a photon measurement system to observe the radiant power emitted from an NiCu multilayer film for a wide energy range, from visible light to mid-infrared light. Using the new system, we attempted to measure the radiation from the sample when a heat burst occurred while anomalous excess heat was being continuously generated. About 10 big burst events were observed during the 5-day continuous measurement: it was found that the radiation intensity increased simultaneously as the heater temperature suddenly increased. We have made a comparison of the radiant spectrum of the burst event with the spectrum in normal times. There is no particular difference due to the burst; both spectra can be simply interpreted as grey body radiation emitted from a thermally equilibrated object. The correlation of radiant intensity between near-IR and visible light has been deduced; although it is expected there is a linear correlation between them, two correlation lines can be drawn instead of one. This indicates that the contribution of photon emission from the non-equilibrium stage may have an effect.