Stimulated radar collider for testing a model of dark energy

We propose a stimulated pulsed-radar collider for testing a dilaton model with the mass of $\sim 10^{-7}$ eV as a candidate of dark energy. 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 sensitivity can reach gravitationally weak coupling domains, 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.