Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Black Hole and Neutron Star Binary Mergers in Triple Systems: II. Merger
  Eccentricity and Spin-Orbit Misalignment   We study the dynamical signatures of black hole (BH) and neutron star (NS)
binary mergers via Lidov-Kozai oscillations induced by tertiary companions in
hierarchical triple systems. For each type of binaries (BH-BH and BH-NS), we
explore a wide range of binary/triple parameters that lead to binary mergers,
and determine the distributions of eccentricity ($e_\mathrm{m}$) and spin-orbit
misalignment angle ($\theta_\rm {sl}^\rm f$) when the binary enters the
LIGO/VIRGO band. We use the double-averaged (over both orbits) and
single-averaged (over the inner orbit) secular equations, as well as N-body
integration, to evolve systems with different hierarchy levels, including the
leading-order post-Newtonian effect, spin-orbit coupling and gravitational
radiation. We find that for merging BH-BH binaries with comparable masses,
about $7\%$ have $e_\mathrm{m}>0.1$ and $0.7\%$ have $e_{\rm m}>0.9$. The
majority of the mergers have significant eccentricities in the LISA band. The
BH spin evolution and $\theta_\rm {sl}^\rm f$ are correlated with the orbital
evolution and $e_{\rm m}$. Mergers with $e_{\rm m} \lesssim 10^{-3}$ have a
distribution of $\theta_\rm {sl}^\rm f$ that peaks around $90^\circ$ (and thus
favoring a projected binary spin parameter $\chi_{\rm eff}\sim 0$), while
mergers with larger $e_{\rm m}$ have a more isotropic spin-orbit misalignments.
For typical BH-NS binaries, strong octuple effects lead to more mergers with
non-negligible $e_\mathrm{m}$ (with $\sim 18\%$ having $e_\mathrm{m}>0.1$ and
$2.5\%$ having $e_\mathrm{m}>0.9$), and the final BH spin axis tends to be
randomly orientated. Measurements or constraints on eccentric mergers and
$\theta_\rm {sl}^\rm f$ from LIGO/VIRGO and LISA would provide useful
diagnostics on the dynamical formation of merging BH or NS binaries in triples.

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The categories of this paper are: atom-ph
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The categories of this paper are: alg-geom
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The categories of this paper are: q-alg
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The categories of this paper are: nucl-ex
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The categories of this paper are: math
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The categories of this paper are: comp-gas
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The categories of this paper are: chem-ph
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The categories of this paper are: solv-int
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The categories of this paper are: hep-ph
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The categories of this paper are: bayes-an
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The categories of this paper are: hep-th
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The categories of this paper are: q-bio
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The categories of this paper are: supr-con
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The categories of this paper are: chao-dyn
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The categories of this paper are: econ
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The categories of this paper are: q-fin