3.5 Going further
The background of GW emission from a population of core collapse SNe at cosmological
distances may be detectable by LIGO-II, according to Ferrari, Matarrese, and Schneider [69].
They determined the SN rate as a function of redshift using observations to determine the
evolution of the star formation rate. Only collapses that lead to black hole formation were
considered. This simplified the study because the GW emission from such collapses is generally a
function of just the black hole mass and angular momentum. They found that the stochastic
background from these sources is not continuous and suggest that this could be used to optimize
detection strategies. The maximum GW spectral strain amplitude they computed was in the range
, at frequencies of a few times
. Such a signal may be detected by a
pair of LIGO-II detectors. Buonanno et al. [38] have recently redone such a study with all
the current results on supernovae, arguing that the GW background would be detectable by
second-generation (e.g., Big Bang Observatory) space-based detectors, noting that Pop III
(black-hole forming stars) could well dominate the total background.Update