John Veitch edited injected dist.tex  almost 9 years ago

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We have restricted our simulation to the first year of the advanced-detector era, using the 2015 simulations from \citet{Singer_2014}. For this, Gaussian noise was generated using the `early' 2015 aLIGO noise curve found in \citet{Barsotti:2012}. Approximately 50,000 BNS sources were simulated with component masses uniformly distributed between $1.2~\mathrm{M}_\odot$ and $1.6~\mathrm{M}_\odot$. Spins were isotropically oriented, with magnitudes $\chi_{1,2} = c |\mathbf{S}_{1,2}|/G m_{1,2}^2$ drawn uniformly between $0$ and $0.05$; here $|\mathbf{S}_{1,2}|$ are the NSs' spin angular momenta and $m_{1,2}$ their mass, the indices $1$ and $2$ correspond to the more and less massive components of the binary respectively. The range of simulated spin magnitudes was chosen to be consistent with the observed population of BNS systems, currently bounded by PSR J0737$-$3039A \citep{Burgay_2003,Brown_2012} from above. Finally, sources were distributed uniformly in volume (i.e. uniform in distance cubed) to a maximum distance at which the loudest signal would produce a network signal-to-noise ratio (S/N) of $\rho_\mathrm{net} = 5$ \citep{Singer_2014}.  Of this simulated population, detectable sources were selected using the \textsc{gstlal\_inspiral} matched-filter detection pipeline \citep{Cannon_2012} with a single-detector S/N threshold $\rho>4$ and false alarm rate (FAR) threshold of $\mathrm{FAR}<10^{-2}~\mathrm{yr}^{-1}$. The FAR for real detector noise is largely governed by non-stationary noise transients in the data that can mimic GWs from compact binary mergers. Because our simulated noise is purely stationary and Gaussian with no such artifacts, FAR estimates are overly optimistic.\footnote{\citet{Berry_2015} demonstrate that the the presence of non-Gaussian features in the noise, as expected in reality, makes negligible difference to parameter estimation.} To compensate, an additional threshold on the network S/N of $\rho_\mathrm{net} > 12$ was applied. This S/N threshold is consistent with the above FAR threshold when applied to data similar to previous science runs \cite{2013arXiv1304.0670L,Berry_2014}. See \citet{Singer_2014} for more details regarding the simulated data and \textsc{gstlal\_inspiral} analyses.