Cosmic background of gravitational waves from rotating neutron stars

The extragalactic background of gravitational waves produced by tri-axial rotating neutron stars was calculated, under the assumption that the properties of the underlying pulsar population are the same of those of the galactic population, recently derived by Regimbau & de Freitas Pacheco (2000). For an equatorial ellipticity of epsilon = 10(-6), the equivalent density parameter due to gravitational waves has a maximum amplitude in the range 2 x 10(-11) 3 x 10(-9), around 0.9-1.5 kHz. The main factors affecting the theoretical predictions are discussed. This background is comparable to that produced by the "ring-down" emission from distorted black holes. The detection possibility of this background by a future generation of gravitational antennas is also examined.