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We compare binary evolution models with different assumptions about black-hole natal kicks to the first gravitational-wave observations performed by the LIGO detectors. Our comparisons attempt to reconcile merger rate, masses, spins, and spin-orbit misalignments of all current observations with state-of-the-art formation scenarios of binary black holes formed in isolation. We estimate that black holes (BHs) should receive natal kicks at birth of the order of $sigmasimeq 200$ (50) km/s if tidal processes do (not) realign stellar spins. Our estimate is driven by two simple factors. The natal kick dispersion $sigma$ is bounded from above because large kicks disrupt too many binaries (reducing the merger rate below the observed value). Conversely, the natal kick distribution is bounded from below because modest kicks are needed to produce a range of spin-orbit misalignments. A distribution of misalignments increases our models compatibility with LIGOs observations, if all BHs are likely to have natal spins. Unlike related work which adopts a concrete BH natal spin prescription, we explore a range of possible BH natal spin distributions. Within the context of our models, for all of the choices of $sigma$ used here and within the context of one simple fiducial parameterized spin distribution, observations favor low BH natal spin.
Some fraction of compact binaries that merge within a Hubble time may have formed from two massive stars in isolation. For this isolated-binary formation channel, binaries need to survive two supernova (SN) explosions in addition to surviving common-
The origin of ultra-wide massive binaries (orbital separations $10^3-2times 10^5$~AU) and their properties are not well characterized nor understood. Here we use the second Gaia data release to search for wide astrometric companions to Galactic O-B5
Based on recent results from three-dimensional supernova simulations and semi-analytical parametrised models, we develop analytical prescriptions for the dependence of the mass of neutron stars and black holes and the natal kicks, if any, on the pre-
In this work we study the formation of the first two black hole-neutron star (BHNS) mergers detected in gravitational waves (GW200115 and GW200105) from massive stars in wide isolated binary systems - the isolated binary evolution channel. We use 560
We investigate the conditions for radio emission in rotating and oscillating magnetars, by focusing on the main physical processes determining the position of their death-lines in the P-dot{P} diagram, i.e. of those lines that separate the regions wh