The gravitational-wave signal generated by a galactic population of
  double neutron-star binaries
  We investigate the gravitational wave (GW) signal generated by a population
of double neutron-star binaries (DNS) with eccentric orbits caused by kicks
during supernova collapse and binary evolution. The DNS population of a
standard Milky-Way type galaxy has been studied as a function of star formation
history, initial mass function (IMF) and metallicity and of the binary-star
common-envelope ejection process. The model provides birth rates, merger rates
and total numbers of DNS as a function of time. The GW signal produced by this
population has been computed and expressed in terms of a hypothetical space GW
detector (eLISA) by calculating the number of discrete GW signals at different
confidence levels, where `signal' refers to detectable GW strain in a given
frequency-resolution element. In terms of the parameter space explored, the
number of DNS-originating GW signals is greatest in regions of recent star
formation, and is significantly increased if metallicity is reduced from 0.02
to 0.001, consistent with Belczynski10a. Increasing the IMF power-law index
(from --2.5 to --1.5) increases the number of GW signals by a large factor.
This number is also much higher for models where the common-envelope ejection
is treated using the $\alpha-$mechanism (energy conservation) than when using
the $\gamma-$mechanism (angular-momentum conservation). We have estimated the
total number of detectable DNS GW signals from the Galaxy by combining
contributions from thin disc, thick disc, bulge and halo. The most probable
numbers for an eLISA-type experiment are 0-1600 signals per year at
S/N$\geqslant$1, 0-900 signals per year at S/N$\geqslant$3, and 0-570 at
S/N$\geqslant$5, coming from about 0-65, 0-60 and 0-50 resolved DNS
respectively.
