Photon and neutrino-pair emission from circulating quantum ions

The recent proposal of photon and neutrino pair beam is extensively investigated. Production rates, both differential and total, of single photon, two-photon and neutrino-pair emitted from quantum ions in circular motion are calculated for any velocity of ion. This part is an extension of our previous results at highest energies to lower energies of circulating ions, and helps much to identify the new process at a low energy ion ring. We clarify how to utilize the circulating ion for a new source of coherent neutrino beam despite of much stronger background photons. Once one verifies that the coherence is maintained in the initial phases of time evolution after laser irradiation, large background photon emission rates are not an obstacle against utilizing the extracted neutrino pair beam.