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تسجيل مستخدم جديدHints of spin-orbit resonances in the binary black hole population
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Binary black hole spin measurements from gravitational wave observations can reveal the binarys evolutionary history. In particular, the spin orientations of the component BHs within the orbital plane, $phi_1$ and $phi_2$, can be used to identify binaries caught in the so-called spin-orbit resonances. In a companion paper, we demonstrate that $phi_1$ and $phi_2$ are best measured near the merger of the two black holes. In this work, we use these spin measurements to constrain the distribution of $phi_1$ and $Delta phi=phi_1 - phi_2$ over the astrophysical population of merging binary black holes. We find that there is a preference for $Delta phi sim pm pi$ in the population, which can be a signature of spin-orbit resonances. We also find a preference for $phi_1 sim -pi/4$ with respect to the line of separation near merger, which has not been predicted for any astrophysical formation channel. However, the strength of these preferences depend on our prior choices, and we are unable to constrain the widths of the $phi_1$ and $Delta phi$ distributions. Therefore, more observations are necessary to confirm the features we find. Finally, we derive constraints on the distribution of recoil kicks in the population, and use this to estimate the fraction of merger remnants retained by globular and nuclear star clusters.
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Binary black hole spins are among the key observables for gravitational wave astronomy. Among the spin parameters, their orientations within the orbital plane, $phi_1$, $phi_2$ and $Delta phi=phi_1-phi_2$, are critical for understanding the prevalenc
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