Stimulated radar collider for probing gravitationally weak coupling pseudo Nambu-Goldstone bosons

bstract We propose a stimulated pulsed-radar collider to directly produce pseudo Nambu-Goldstone bosons as candidates for dark components in the Universe and simultaneously induce the decay by mixing two radar beams. We have extended formulae for stimulated resonant photon-photon scattering in a quasi-parallel collision system by including fully asymmetric collision cases. With a pulse energy of 100 J in the GHz-band, for instance, which is already achieved by an existing klystron, we expect that the model-independent sensitivity can reach gravitationally weak coupling domains at a mass range 10 − 7 –10 − 6 eV, if two key technological issues are resolved: pulse compression in time reaching the Fourier transform limit, and single-photon counting for GHz-band photons. Such testing might extend the present horizon of particle physics.