Gravitational waves from galaxy clusters: A new observable effect

A rich galaxy cluster showing strong resemblance to the observed ones is simulated. A cold dark matter spectrum, Gaussian statistics, a flat universe, and two components (baryonic gas plus dark matter particles) are considered. We have calculated the gravitational-wave output during the epoch of the fully nonlinear and nonsymmetric cluster evolution. The amplitudes and frequencies of the resulting gravitational waves are estimated. Since frequencies are very small-of the order of 10(-17) Hz-a complete pulse cannot be observed during an admissible integration time; nevertheless, it is proved that these waves can produce an interesting secular effect, which appears to be observable with current technology.