In the first interval after the initial 1% duty factor CO2 laser heating "pulse", the 532-nmexcited APD signal was ~20,000 counts/second, which is well above the baseline level, and the emission spectrum recorded at that time (blue curve Fig. ) was blackbody-like, corresponding to TNP = 1184 K. Only a single Fz resonance (green dot) was observed (Fz ≈ 1.9 kHz), indicating that a single NP with Fz in the 0.1 to 10 kHz Fz scan range was present. Given that no 532 nmexcited emission was observed before the CO2 laser heating pulse, it is clear that at least one trapped NP transformed irreversibly under 10.6 μm heating, increasing its 532 nm absorptivity (allowing heating in incandescence), and conferring blackbody-like emission properties.