The one thing that many of these replication attempts have in common is an apparent threshold temperature of about 1200C before gain starts.
It would be helpful and intuitive, moving forward, to know what this temperature relates to, exactly. For instance, is this a threshold in photon resonance in the SPP formation process? It could also relate to a phase-change in a fuel component, or many other unknown parameters as well. There is a simple way to find out one datum insofar as it relates to SPP– at least for those reactors like the glow-tube which are not enclosed in a dewar of some kind, like the Chinese setup. As it happens, the typical 40 watt incandescent bulb, produced by the billions and cheap, coincidentally has a surface temperature of a little over 1200C. Using a parabolic lamp reflector, such as a study-lamp, it would be possible to use 2 or 3 lamps to irradiate a glow tube in such a way that more photons of IR corresponding to 1200C are available, compared with the inefficiency of the resistance wire heater. This way the tube does not have to shed 95% of the heat that it does not use. (assuming SPP are the relevant parameter). IOW we are trying to add superradiance of the Preparata-Dicke variety to substitute for low value heat. In effect, 120 watts could probably be a good substitute for ~1000 watts often used if we are only concerned with the peak photon irradiance (for SPP) and not the broad blackbody thermal load. From: Jed Rothwell Here is Fig. 8 with my rough translations in orange text: https://drive.google.com/file/d/0B6qvuFUMAp9HT2taZ0hBMjYtS1U/view?usp=sharing
