Detecting cold dark-matter candidates

We consider the use of superheated superconducting colloids as detectors of weakly interacting galactic-halo candidate particles (e.g., photinos, massive neutrinos, and scalar neutrinos). We discuss realistic models for the detector and for the galactic halo. We show that the expected count rate (≊${10}^3$ count/day for scalar and massive neutrinos) exceeds the expected background by several orders of magnitude. For photinos, we expect ≊1 count/day, more than 100 times the predicted background rate. We find that if the detector temperature is maintained at 50 mK and using SQUID electronic read out with the system, noise is reduced below 5×${10}^{\mathrm{-}4}$ flux quanta, particles with mass as low as 2 GeV can be detected. Any particle capable of resolving the solar-neutrino problem by altering energy transport in the Sun can be detected. We show that Earth’s motion around the Sun can produce a significant annual modulation in the signal.