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Directly comparing GW150914 with numerical solutions of Einsteins equations for binary black hole coalescence

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 نشر من قبل LVC Publications
 تاريخ النشر 2016
  مجال البحث فيزياء
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We compare GW150914 directly to simulations of coalescing binary black holes in full general relativity, accounting for all the spin-weighted quadrupolar modes, and separately accounting for all the quadrupolar and octopolar modes. Consistent with the posterior distributions reported in LVC_PE[1] (at 90% confidence), we find the data are compatible with a wide range of nonprecessing and precessing simulations. Followup simulations performed using previously-estimated binary parameters most resemble the data. Comparisons including only the quadrupolar modes constrain the total redshifted mass Mz in [64 - 82M_odot], mass ratio q = m2/m1 in [0.6,1], and effective aligned spin chi_eff in [-0.3, 0.2], where chi_{eff} = (S1/m1 + S2/m2) cdothat{L} /M. Including both quadrupolar and octopolar modes, we find the mass ratio is even more tightly constrained. Simulations with extreme mass ratios and effective spins are highly inconsistent with the data, at any mass. Several nonprecessing and precessing simulations with similar mass ratio and chi_{eff} are consistent with the data. Though correlated, the components spins (both in magnitude and directions) are not significantly constrained by the data. For nonprecessing binaries, interpolating between simulations, we reconstruct a posterior distribution consistent with previous results. The final black holes redshifted mass is consistent with Mf,z between 64.0 - 73.5M_odot and the final black holes dimensionless spin parameter is consistent with af = 0.62 - 0.73. As our approach invokes no intermediate approximations to general relativity and can strongly reject binaries whose radiation is inconsistent with the data, our analysis provides a valuable complement to LVC_PE[1].


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