Two independent axion searches have been carried out near a well-shielded radioactive Zn65 source (15 kCi). One experiment used four NaI(Tl) scintillators to detect coincident photons generated in the decay a. The second used a shielded 145-cm3 low-background intrinsic-Ge detector to detect single photons produced by axion Compton interactions with detector electrons and by Primakoff conversion off Ge nuclei and off Pb nuclei in the detector shield. We determine general constraints imposed by these experiments on axions that couple to nucleons and to either the electron or two photons. In the case of light axions, the limits obtained in the second experiment are new. For the standard axion, we determine the ranges of f and X that are ruled out by our measurements.
All Science Journal Classification (ASJC) codes
- Nuclear and High Energy Physics