A NEXT-GENERATION CAVITY MICROWAVE EXPERIMENT TO SEARCH FOR DARK-MATTER AXIONS

We propose a large-scale experimental search for dark-matter axions which may constitute an important fraction of our own galactic halo. As shown by Sikivie,(1) dark-matter axions may be detected by their stimulated conversion into monochromatic microwave photons in a tunable high-and cavity inside a strong magnetic field. The principal improvement in power sensitivity over two earlier pilot experiments (x 25) derives from the large-volume high field superconducting magnet (the NASA SUMMA coils). The improvement in mass range (1.5 to 12.6 mu eV) will result from the use of several microwave cavity arrays, of 2(n) cavities each, over the course of the experimental program, rather than a single cavity. We are participating in a joint venture with the Institute for Nuclear Research of the Russian Academy of Sciences to do R&D on metalized precision-formed ceramic microwave cavities for the axion search.