The problem of cosmic ray noise in gravitational wave detectors

It is well known that the high sensitivity required of gravitational wave detectors calls for the utmost care in trying to understand quantitatively the effect of every conceivable disturbance. Among the causes of disturbance it has been suggested that cosmic rays striking a 'resonator bar' type of detector may excite potentially harmful mechanical vibrations. One means of wighing the importance of this effect is offered by the study of the mechanical oscillations induced in solids by the impact of beams of artificially accelerated charged particles. We felt however that, in order to gain a better understanding, the precision of the measurements had to be improved. Therefore we performed new measurements, employing beams of protons as well as of electrons, and shall describe our experiments presently. (orig.)