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We explore the newly discovered "hangup-kick" effect, which greatly amplifies the recoil for configurations with partial spin-/orbital angular momentum alignment, by studying a set of 48 new simulations of equal-mass, spinning black-hole binaries. We propose a phenomenological model for the recoil that takes this new effect into account and then use this model, in conjunction with statistical distributions for the spin magnitude and orientations, based on accretion simulations, to find the probabilities for observing recoils of several thousand km s-1. In addition, we provide initial parameters, eccentricities, radiated linear and angular momentum, precession rates and remnant mass, spin, and recoils for all 48 configurations. Our results indicate that surveys exploring peculiar (redshifted or blueshifted) differential line-of-sight velocities should observe at least one case above 2000 kms -1 out of 4000 merged galaxies. On the other hand, the probability that a remnant black hole recoils in any direction at a velocity exceeding the --2000 km s-1 escape velocity of large elliptical galaxies is 0.03%. Probabilities of recoils exceeding the escape velocity quickly rise to 5% for galaxies with escape velocities of 1000 kms-1 and nearly 20% for galaxies with escape velocities of 500 kms-1. In addition the direction of these large recoils is strongly peaked toward the angular momentum axis, with very low probabilities of recoils exceeding 350 km s∼ ' for angles larger than 45° with respect to the orbital angular momentum axis. [ABSTRACT FROM AUTHOR]

The massive black holes we observe in galaxies today are the natural end-product of a complex evolutionary path, in which black holes seeded in proto-galaxies at high redshift grow through cosmic history via a sequence of mergers and accretion episodes. Electromagnetic observations probe a small subset of the population of massive black holes (namely, those that are active or those that are very close to us), but planned space-based gravitational wave observatories such as the Laser Interferometer Space Antenna (LISA) can measure the parameters of "electromagnetically invisible" massive black holes out to high redshift. In this paper we introduce a Bayesian framework to analyze the information that can be gathered from a set of such measurements. Our goal is to connect a set of massive black hole binary merger observations to the underlying model of massive black hole formation. In other words, given a set of observed massive black hole coalescences, we assess what information can be extracted about the underlying massive black hole population model. For concreteness we consider ten specific models of massive black hole formation, chosen to probe four important (and largely unconstrained) aspects of the input physics used in structure formation simulations: seed formation, metallicity "feedback", accretion efficiency and accretion geometry. For the first time we allow for the possibility of "model mixing", by drawing the observed population from some combination of the "pure" models that have been simulated. A Bayesian analysis allows us to recover a posterior probability distribution for the "mixing parameters" that characterize the fractions of each model represented in the observed distribution. Our work shows that LISA has enormous potential to probe the underlying physics of structure formation. [ABSTRACT FROM AUTHOR]

Massive black hole binaries (MBHBs) of 105 M⊙-3×107 M⊙ merging in low redshift galaxies (z≤4) are sufficiently loud to be detected weeks before coalescence with the Laser Interferometer Space Antenna (LISA). This allows us to perform the parameter estimation on the fly, i.e., as a function of the time to coalescence during the inspiral phase, relevant for early warning of the planned LISA protected periods and for searches of electromagnetic signals. In this work, we study the evolution of the sky position, luminosity distance, chirp mass and mass ratio uncertainties as function of time left before merger. Overall, light systems with total intrinsic mass Mtot=3×105 M⊙ are characterized by smaller uncertainties than heavy ones (Mtot=107 M⊙) during the inspiral. Luminosity distance, chirp mass and mass ratio are well constrained at the end of the inspiral. Concerning sky position, at z=1, MBHBs with Mtot=3×105 M⊙ can be localized with a median precision of ≃10² deg²(≃1 deg²) at 1 month (1 hour) from merger, while the sky position of heavy MBHBs can be determined to 10 deg² only 1 hour before merger. However the uncertainty around the median values broadens with time, ranging in between 0.04-20 deg² (0.3-3×10³ deg²) for light (heavy) systems at 1 hour before merger. At merger the sky localization improves down to ≃10-1 deg² for all masses. For the benefit of the observer community, we provide the full set of data from our simulations and simple and ready-to-use analytical fits to describe the time evolution of uncertainties in the aforementioned parameters, valid for systems with total mass between 105-107 M⊙ and redshift 0.3-3. [ABSTRACT FROM AUTHOR]