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تسجيل مستخدم جديدConstraining Recoiling Velocities of Black Holes Ejected by Gravitational Radiation in Galaxy Mergers
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Recent general relativistic simulations have shown that the coalescence of two spinning black holes (BH) can lead to recoiling speeds of the BH remnant of up to thousands of km/s as a result of the gravitational radiation emission. It is important that the accretion disc remains bound to ejected BH within the region where the gas orbital velocity is larger than the ejection speed. We considered the situation when the recoiling kick radius coincides with the radius of the broad line region (BLR). We show that in this situation the observed polarization data of accretion disk emission allow to determine the value of the recoil velocity. We present the estimates of the kick velocity for AGN with determined polarization data.
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We follow trajectories of recoiling supermassive black holes (SMBHs) in analytical and numerical models of galaxy merger remnants with masses of $10^{11} rm{M_{sun}}$ and $10^{12} rm{M_{sun}}$. We construct various merger remnant galaxies in order to
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Binary black holes emit gravitational radiation with net linear momentum leading to a retreat of the final remnant black hole that can reach up to $sim5,000$ km/s. Full numerical relativity simulations are the only tool to accurately compute these re
coils since they are largely produced when the black hole horizons are about to merge and they are strongly dependent on their spin orientations at that moment. We present eight new numerical simulations of BBH in the hangup-kick configuration family, leading to the maximum recoil. Black holes are equal mass and near maximally spinning ($|vec{S}_{1,2}|/m_{1,2}^2=0.97$). Depending on their phase at merger, this family leads to $simpm4,700$ km/s and all intermediate values of the recoil along the orbital angular momentum of the binary system. We introduce a new invariant method to evaluate the recoil dependence on the merger phase via the waveform peak amplitude used as a reference phase angle and compare it with previous definitions. We also compute the mismatch between these hangup-kick waveforms to infer their observable differentiability by gravitational wave detectors, such as advanced LIGO, finding currently reachable signal-to-noise ratios, hence allowing for the identification of highly recoiling black holes having otherwise essentially the same binary parameters.
The coalescence of massive black hole binaries (BHBs) in galactic mergers is the primary source of gravitational waves (GWs) at low frequencies. Current estimates of GW detection rates for the Laser Interferometer Space Antenna and the Pulsar Timing
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Gravitational-wave (GW) recoil of merging supermassive black holes (SMBHs) may influence the co-evolution of SMBHs and their host galaxies. We examine this possibility using SPH/N-body simulations of gaseous galaxy mergers in which the merged BH rece
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Recent simulations of merging black holes with spin give recoil velocities from gravitational radiation up to several thousand km/s. A recoiling supermassive black hole can retain the inner part of its accretion disk, providing fuel for a continuing
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