Successive Mergers Research Articles

The VIMOS Public Extragalactic Redshift Survey (VIPERS): galaxy segregation inside filaments atz≃ 0.7

We present the first quantitative detection of large-scale filamentary structure at $z \simeq 0.7$ in the large cosmological volume probed by the VIMOS Public Extragalactic Redshift Survey (VIPERS). We use simulations to show the capability of VIPERS to recover robust topological features in the galaxy distribution, in particular the filamentary network. We then investigate how galaxies with different stellar masses and stellar activities are distributed around the filaments and find a significant segregation, with the most massive or quiescent galaxies being closer to the filament axis than less massive or active galaxies. The signal persists even after down-weighting the contribution of peak regions. Our results suggest that massive and quiescent galaxies assemble their stellar mass through successive mergers during their migration along filaments towards the nodes of the cosmic web. On the other hand, low-mass star-forming galaxies prefer the outer edge of filaments, a vorticity rich region dominated by smooth accretion, as predicted by the recent spin alignment theory. This emphasizes the role of large scale cosmic flows in shaping galaxy properties.

Distribution of Mass and Energy in Closed Model of the Universe

The universe’s horizon distance and volume are constructed in the closed cosmic model. The universe horizon distance distribution increases constantly for t tme and decreases for t > tme. However, the universe’s horizon volume shows a sudden reduction in the range t = 0.5 Gyr - tme due to the change of the universe space from flat to curved then closed in the interval 15.1261 Gyr ≤ t ≤ tme. On the other hand, this distribution exhibits an abrupt rise in the range t = tme - t* due to the change of the universe space from closed then curved to flat in the interval 39.3822 ≤ t ≤ 40.7521 Gyr. The mass of radiation, matter and dark energy within the horizon volume of the universe are also investigated. These distributions reveal similar noticeable changes as the universe’s horizon volume distribution for the same reasons. The mass of radiation dominates up to t = 53221.5 yr, then the mass of matter becomes larger. Afterwards, both distributions of radiation and matter decrease while the distribution of dark energy rises until t = 10.1007 Gyr, where the mass of dark energy prevails up to t = tme. Hence, the distribution of dark energy reduces until t = 40.2892 Gyr, where the mass of matter becomes prominent again. At t = 53.6246 Gyr the masses of both matter and radiation become appreciably high such that the intercluster space will vanish and clusters of galaxies interfere with each other. Furthermore, not only the intergalactic medium will disappear, but also galaxies will collide and merge with each other to form extremely dense and close cosmological bodies. These very dense bodies will undergo further successive collisions and mergers under the action of central gravity, where the interstellar medium will vanish and the universe would develop to big crunch at tbc = 53.6251 Gyr. It is interesting to note that the horizon distance of the universe in the closed model at t = tme is in very good agreement with the maximum horizon distances in the five general cosmic models.

A systematic computational analysis of biosynthetic gene cluster evolution: lessons for engineering biosynthesis.

Bacterial secondary metabolites are widely used as antibiotics, anticancer drugs, insecticides and food additives. Attempts to engineer their biosynthetic gene clusters (BGCs) to produce unnatural metabolites with improved properties are often frustrated by the unpredictability and complexity of the enzymes that synthesize these molecules, suggesting that genetic changes within BGCs are limited by specific constraints. Here, by performing a systematic computational analysis of BGC evolution, we derive evidence for three findings that shed light on the ways in which, despite these constraints, nature successfully invents new molecules: 1) BGCs for complex molecules often evolve through the successive merger of smaller sub-clusters, which function as independent evolutionary entities. 2) An important subset of polyketide synthases and nonribosomal peptide synthetases evolve by concerted evolution, which generates sets of sequence-homogenized domains that may hold promise for engineering efforts since they exhibit a high degree of functional interoperability, 3) Individual BGC families evolve in distinct ways, suggesting that design strategies should take into account family-specific functional constraints. These findings suggest novel strategies for using synthetic biology to rationally engineer biosynthetic pathways.

The Law on Abuses of Dominance and the System of Judicial Remedies

This article examines the extent to which the imperfect nature of the EU system of judicial remedies can explain the peculiar evolution of the EU law on abuses of dominance. A comprehensive analysis of competition law judgments since the 1960s suggests that the procedural avenue through which a case reaches the General Court and the European Court of Justice has a significant impact on the outcome of individual cases and, over time, on the very substance of Treaty provisions. It is submitted that some of the distinct features of the case law on Article 102 TFEU – lack of consistency, legal uncertainty, judicial restraint – are the consequence of the fact that the scope of the notion of abuse has been defined in the context of annulment actions against Commission decisions, as opposed to preliminary references submitted by national courts in accordance with Article 267 TFEU. This conclusion is tested against the evolution of Article 101 TFEU and Article 2 of the successive Merger Regulations.

Age and metallicity gradients in fossil ellipticals

Fossil galaxy groups are speculated to be old and highly evolved systems of galaxies that formed early in the universe and had enough time to deplete their $L^{*}$ galaxies through successive mergers of member galaxies, building up one massive central elliptical, but retaining the group X-ray halo. Considering that fossils are the remnants of mergers in ordinary groups, the merger history of the progenitor group is expected to be imprinted in the fossil central galaxy (FCG). We present for the first time radial gradients of single-stellar population (SSP) ages and metallicites in a sample of FCGs to constrain their formation scenario. Our sample comprises some of the most massive galaxies in the universe exhibiting an average central velocity dispersion of $\sigma_0=271\pm28$ km s$^{-1}$. Metallicity gradients are throughout negative with comparatively flat slopes of $\nabla_{[\rm{Fe/H}]}=- 0.19\pm0.08$ while age gradients are found to be insignificant ($\nabla_{\rm{age}}=0.00\pm0.05$). All FCGs lie on the fundamental plane, suggesting that they are virialised systems. We find that gradient strengths and central metallicities are similar to those found in cluster ellipticals of similar mass. The comparatively flat metallicity gradients with respect to those predicted by monolithic collapse ($\nabla_{Z}=-0.5$) suggest that fossils are indeed the result of multiple major mergers. Hence we conclude that fossils are not 'failed groups' that formed with a top heavy luminosity function. The low scatter of gradient slopes suggests a similar merging history for all galaxies in our sample.

Coevolution (Or Not) of Supermassive Black Holes and Host Galaxies

Supermassive black holes (BHs) have been found in 85 galaxies by dynamical modeling of spatially resolved kinematics. The Hubble Space Telescope revolutionized BH research by advancing the subject from its proof-of-concept phase into quantitative studies of BH demographics. Most influential was the discovery of a tight correlation between BH mass [Formula: see text] and the velocity dispersion σ of the bulge component of the host galaxy. Together with similar correlations with bulge luminosity and mass, this led to the widespread belief that BHs and bulges coevolve by regulating each other's growth. Conclusions based on one set of correlations from [Formula: see text] in brightest cluster ellipticals to [Formula: see text] in the smallest galaxies dominated BH work for more than a decade.New results are now replacing this simple story with a richer and more plausible picture in which BHs correlate differently with different galaxy components. A reasonable aim is to use this progress to refine our understanding of BH-galaxy coevolution. BHs with masses of 105−106M⊙are found in many bulgeless galaxies. Therefore, classical (elliptical-galaxy-like) bulges are not necessary for BH formation. On the other hand, although they live in galaxy disks, BHs do not correlate with galaxy disks. Also, any [Formula: see text] correlations with the properties of disk-grown pseudobulges and dark matter halos are weak enough to imply no close coevolution.The above and other correlations of host-galaxy parameters with each other and with [Formula: see text] suggest that there are four regimes of BH feedback. (1) Local, secular, episodic, and stochastic feeding of small BHs in largely bulgeless galaxies involves too little energy to result in coevolution. (2) Global feeding in major, wet galaxy mergers rapidly grows giant BHs in short-duration, quasar-like events whose energy feedback does affect galaxy evolution. The resulting hosts are classical bulges and coreless-rotating-disky ellipticals. (3) After these AGN phases and at the highest galaxy masses, maintenance-mode BH feedback into X-ray-emitting gas has the primarily negative effect of helping to keep baryons locked up in hot gas and thereby keeping galaxy formation from going to completion. This happens in giant, core-nonrotating-boxy ellipticals. Their properties, including their tight correlations between [Formula: see text] and core parameters, support the conclusion that core ellipticals form by dissipationless major mergers. They inherit coevolution effects from smaller progenitor galaxies. Also, (4) independent of any feedback physics, in BH growth modes 2 and 3, the averaging that results from successive mergers plays a major role in decreasing the scatter in [Formula: see text] correlations from the large values observed in bulgeless and pseudobulge galaxies to the small values observed in giant elliptical galaxies.

The intriguing life of cD galaxies

cD galaxies are supergiant elliptical galaxies found generally in the central parts of rich clusters, which have an extended halo-like component (envelope) in addition to the underlying de Vaucouleurs-Sérsic elliptical galaxy-like component. This envelope can extend to radial distances of > 500 kpc (Oemler 1976, Schombert 1988). There have been many theories to explain the formation of these envelopes. These include tidal stripping, where material is stripped from neighbouring galaxies; mergers and fusions, where the envelope is built up hierarchically by successive mergers with large and small galaxies; primordial origin, where the envelope is formed at the same time as the rest of the elliptical galaxy (which appears to be related to theories of early formation of the largest galaxies); and cooling flows: in clusters with X-ray emission there is often a minimum temperature in the centre interpreted as a flow of cooling gas towards the centre of the cluster, where the gas can cool sufficiently, forming stars. The colours of the stars in the envelopes will be affected by their process of formation and subsequent evolution.

THE COSMOLOGICAL IMPACT OF LUMINOUS TeV BLAZARS. III. IMPLICATIONS FOR GALAXY CLUSTERS AND THE FORMATION OF DWARF GALAXIES

A subset of blazars emit TeV gamma rays which annihilate and pair produce on the extragalactic background light. We have argued in Broderick et al. (2011, Paper I) that plasma beam instabilities can dissipate the pairs' energy locally. This heats the intergalactic medium and dramatically increases its entropy after redshift z~2, with important implications for structure formation: (1) This suggests a scenario for the origin of the cool core (CC)/non-cool core (NCC) bimodality in galaxy clusters and groups. Early forming galaxy groups are unaffected because they can efficiently radiate the additional entropy, developing a CC. However, late forming groups do not have sufficient time to cool before the entropy is gravitationally reprocessed through successive mergers - counteracting cooling and raising the core entropy further. Hence blazar heating works different than feedback by active galactic nuclei, which balances radiative cooling but is unable to transform CC into NCC clusters due to the weak coupling to the cluster gas. (2) We predict a suppression of the Sunyaev-Zel'dovich power spectrum on angular scales smaller than 5' due to the globally reduced central pressure of groups and clusters forming after z~1. (3) Our redshift dependent entropy floor increases the characteristic halo mass below which dwarf galaxies cannot form by a factor of ~10 (50) at mean density (in voids) over that found in models that include photoionization alone. This prevents the formation of late forming dwarf galaxies (z<2) with masses ranging from 10^{10} to 10^{11} M_sun for redshifts z~2 to 0, respectively. This may help resolve the "missing satellite problem" in the Milky Way and the "void phenomenon" of the low observed abundances of dwarf satellites compared to cold dark matter simulations and may bring the observed early star formation histories into agreement with galaxy formation models. (abridged)

The Collapse of a European Bank in the Financial Crisis: An Analysis from Stakeholder and Ethical Perspectives

Fortis, the leading Benelux financial group, had been a success story of successive mergers of bank and insurance companies, with leadership in corporate social responsibility (CSR). One year after the acquisition of the major Dutch financial conglomerate ABN AMRO, the global financial crisis caused the collapse of the Fortis group. The purpose of this article is to use the case study of Fortis’s recent fall as a basis for reflective considerations on the financial crisis, from stakeholder and ethical perspectives. A selected number of key events of the history of the dramatic crisis at Fortis will be analysed from different ethical frameworks. Special consideration will be given to fairness of communication, shareholder activism and conflicts of interests of CEO’s mergers opportunities. A confrontation between the CSR policy and the reality raises the fundamental questions why the powerful CSR guidelines and ethical principles did not help in the assessment of the risks.

SUCCESSIVE MERGER OF MULTIPLE MASSIVE BLACK HOLES IN A PRIMORDIAL GALAXY

Using highly-accurate $N$-body simulations, we explore the evolution of multiple massive black holes (hereafter, MBHs) in a primordial galaxy that is composed of stars and MBHs. The evolution is pursed with a fourth-order Hermite scheme, where not only three-body interaction of MBHs but also dynamical friction by stars are incorporated. Initially, ten MBHs with equal mass of $10^7M_\odot$ are set in a host galaxy with $10^{11}M_\odot$. It is found that 4 - 6 MBHs merge successively within 1 Gyr, emitting gravitational wave radiation. The key process for the successive merger of MBHs is the dynamical friction by field stars, which enhances three-body interactions of MBHs when they enter the central regions of the galaxy. The heaviest MBH always composes a close binary at the galactic center, which shrinks owing to the angular momentum transfer by the third MBH and eventually merges. The angular momentum transfer by the third MBH is due to the sling-shot mechanism. We find that the secular Kozai mechanism does not work for a binary to merge if we include the relativistic pericenter shift. The simulations show that a multiple MBH system can produce a heavier MBH at the galactic center purely through $N$-body process. This merger path can be of great significance for the growth of MBHs in a primordial galaxy. The merger of multiple MBHs may be a potential source of gravitational waves for the Laser Interferometer Space Antenna (LISA) and pulsar timing.

The orbital decay of embedded binary stars

Young binaries within dense molecular clouds are subject to dynamical friction from ambient gas. Consequently, their orbits decay, with both the separation and period decreasing in time. A simple analytic expression is derived for this braking torque. The derivation utilizes the fact that each binary acts as a quadrupolar source of acoustic waves. The acoustic disturbance has the morphology of a two-armed spiral and carries off angular momentum. From the expression for the braking torque, the binary orbital evolution is also determined analytically. This type of merger may help explain the origin of high-mass stars. If infrared dark clouds, with peak densities up to 10^7 cm^{-3}, contain low-mass binaries, those with separations less than 100 AU merge within about 10^5 yr. During the last few thousand years of the process, the rate of mechanical energy deposition in the gas exceeds the stars' radiative luminosity. Successive mergers may lead to the massive star formation believed to occur in these clouds.

The VIMOS VLT Deep Survey

<i>Context. <i/>The rate at which galaxies grow via successive mergers is a key element in understanding the main phases of galaxy evolution.<i>Aims. <i/>We measure the evolution of the fraction of galaxies in pairs and the merging rate since redshift <i>z<i/> ~ 1 assuming a (<i>H<i/><sub>0<sub/> = 70 km s<sup>-1<sup/> Mpc<sup>-1<sup/>, = 0.3 and = 0.7) cosmology.<i>Methods. <i/>From the VIMOS VLT Deep Survey we use a sample of 6464 galaxies with <i>I<i/><sub>AB<sub/><i>≤<i/> 24 to identify 314 pairs of galaxies, each member with a secure spectroscopic redshift, which are close in both projected separation and in velocity.<i>Results. <i/>We estimate that at <i>z<i/> ~ 0.9, 10.9 <i>±<i/> 3.2% of galaxies with <i>≤<i/> -18-Qz (<i>Q<i/> = 1.11) are in pairs with separations <i>≤<i/> 20 h<sup>-1<sup/> kpc, <i>≤<i/> 500 km s<sup>-1<sup/>, and with <i>≤<i/> 1.5, significantly larger than 3.8 <i>±<i/> 1.7% at <i>z<i/> ~ 0.5; thus, the pair fraction evolves as (1 + <i>z<i/>)<sup><i>m<i/><sup/> with <i>m<i/> = 4.73 <i>±<i/> 2.01. For bright galaxies with <i>≤<i/> -18.77, the pair fraction is higher and its evolution with redshift is flatter with <i>m<i/> = 1.50 <i>±<i/> 0.76, a property also observed for galaxies with increasing stellar masses. Early-type pairs (dry mergers) increase their relative fraction from 3% at <i>z<i/> ~ 0.9 to 12% at <i>z<i/> ~ 0.5. The star formation rate traced by the rest-frame [OII] <i>EW<i/> increases by 26 <i>±<i/> 4% for pairs with the smallest separation <i>r<i/><sub>p<sub/><i>≤<i/> 20 h<sup>-1<sup/> kpc. Following published prescriptions to derive merger timescales, we find that the merger rate of -18-Qz galaxies evolves as <i>N<i/><sub>mg<sub/> = (4.96 <i>±<i/> 2.07)10<sup>-4<sup/> mergers Mpc<sup>-3<sup/> Gyr<sup>-1<sup/>.<i>Conclusions. <i/>The merger rate of galaxies with <i>≤<i/> -18-Qz has significantly evolved since <i>z<i/> ~ 1 and is strongly dependent on the luminosity or stellar mass of galaxies. The major merger rate increases more rapidly with redshift for galaxies with fainter luminosities or stellar mass, while the evolution of the merger rate for bright or massive galaxies is slower, indicating that the slow evolution reported for the brightest galaxies is not universal. The merger rate is also strongly dependent on the spectral type of galaxies involved. Late-type mergers were more frequent in the past, while early-type mergers are more frequent today, contributing to the rise in the local density of early-type galaxies. About 20% of the stellar mass in present day galaxies with <i>≥<i/> 9.5 has been accreted through major merging events since <i>z<i/> = 1. This indicates that major mergers have contributed significantly to the growth in stellar mass density of bright galaxies over the last half of the life of the Universe.

Rebranding in the banking industry following mergers and acquisitions

Purpose – This paper aims to examine how international banking groups manage their branding in the context of successive mergers and acquisitions. It seeks to review of a number of case histories in order to show that banking companies tend to evolve a multi‐tiered system for absorbing and rebranding acquisitions and it also seeks to present a general framework to guide future research and practice.Design/methodology/approach – The banking industry has been undergoing major consolidation in recent years, with a number of global players emerging through successive mergers and acquisitions. These transactions vary in scale and location, from major mergers of large, equal‐sized international entities to acquisitions of smaller, local businesses in various countries all around the world. This paper brings together the literature on mergers and acquisitions, which mostly comes from economics and finance, with the marketing literature on branding and rebranding, to create a framework to help us to understand th...

Jealous Monopolists? British Banks and Responses to the Macmillan Gap during the 1930s

By the end of World War I successive merger waves had produced an oligopolistic, tightly cartelized, English banking system, which was widely viewed as having restricted lending to small-medium-sized firms—the famous 'Macmillan Gap' in industrial finance. We explore the reasons behind the failure of market entry to bridge this gap. The clearing banks are shown to have acted as 'jealous monopolists', obstructing the activities of the Credit for Industry Ltd (CFI), the only significant firm established to breach the gap (rather than narrow its upper limit). By poaching many clients it had vetted and approved, the banks blocked CFI's growth, deterring further market entry, and thus, preserving their monopoly position.

Jealous Monopolists? British Banks and Responses to the Macmillan Gap during the 1930s

By the end of World War I successive merger waves had produced an oligopolistic, tightly cartelized, English banking system, which was widely viewed as having restricted lending to small-medium-sized firms—the famous 'Macmillan Gap' in industrial finance. We explore the reasons behind the failure of market entry to bridge this gap. The clearing banks are shown to have acted as 'jealous monopolists', obstructing the activities of the Credit for Industry Ltd (CFI), the only significant firm established to breach the gap (rather than narrow its upper limit). By poaching many clients it had vetted and approved, the banks blocked CFI's growth, deterring further market entry, and thus, preserving their monopoly position.

Turbulent cascade in vortex dynamics of magnetized pure electron plasmas

Elementary processes in free-decaying two-dimensional (2D) turbulence are examined by extensive analyses of fine structures in the density distribution of a magnetized pure electron plasma that is linearly unstable with the initial ring-shaped profile, deforms nonlinearly into patches of vortices, and relaxes into a single-peaked stable distribution via successive mergers among the patches. The stochastic dynamics of the decreasing number of vortices in the real space correspond to the time evolution of energy spectra E(k) in the wave number (k) space that the energy transfers down to lower k while the upward-spreading tails of the spectra fit to the power-law (proportional k(-alpha)) with alpha > 3. The transfer rates, epsilon(k) and eta(k) in energy and enstrophy spaces, evaluated from the time-resolved k -spectra demonstrate characteristic features of the 2D turbulence, i.e., epsilon(k) is negative and deepest below the k(inj) corresponding to the size of the first-generated patches, and eta(k) increases from zero to a constant value at k > k(inj). By averaging the time-dependent spectra of E(k), epsilon(k), and eta(k), constructions are carried out for the spectra in a stationary turbulence that is sustained by the continuous generation of vortices due to the instability and dissipation at high k. The spectra are qualitatively consistent with the 2D turbulence theory with discrepancies including that alpha approximately 4.4 and that the enstrophy transfer rate is almost zero around k = k(inj) reflecting the contribution from the coherent vortices.

Dynamics of compact object clusters: a post-Newtonian study

Abstract Compact object clusters are likely to exist in the centres of some galaxies because of mass segregation. The high densities and velocities reached in them need a better understanding. The formation of binaries and their subsequent merging by gravitational radiation emission are important to the evolution of such clusters. We address the evolution of such a system in a relativistic regime. The recurrent mergers at high velocities create an object with a mass much larger than the average. For this purpose we modified the direct Nbody6++ code to include post-Newtonian effects on the force during two-body encounters. We adjusted the equations of motion to include for the first time the effects of both periastron shift and energy loss by emission of gravitational waves, and so to study the eventual decay and merger of radiating binaries. The method employed allows us to give here an accurate post-Newtonian description of the formation of a runaway compact object by successive mergers with surrounding particles, as well as the distribution of characteristic eccentricities in the events. This study should be envisaged as a first step towards a detailed, accurate study of possible gravitational wave sources, thanks to the combination of the direct Nbody numerical tool with the implementation of post-Newtonian terms.

Perspective on the drug discovery and market landscape in Japan: can it compete in the worldwide arena?

The global pharmaceutical industry is described as facing an ‘innovation crisis’ following the ‘go-go-pharma’ era; in other words, the problem is one of ‘more money and fewer products’. Nevertheless, patients worldwide are awaiting innovative drugs. Therefore, the pharmaceutical industry has a duty to discover and develop novel drugs and medical technologies. Through universal coverage and reform of the patent system, the Japanese pharmaceutical industry has expanded greatly in line with the Japanese economy. However, in terms of scale and R&D investment, the Japanese pharmaceutical firms have lagged behind the foreign multinationals, which have undergone successive mergers and acquisitions. Meanwhile, it is true that several Japanese firms are playing an active role in overseas markets with their own blockbusters. This paper analyses and gives an overview of new trends in Japan’s pharmaceutical industry within the global context.

The effect of gravitational recoil on black holes forming in a hierarchical universe

Galactic bulges are known to harbour central black holes whose mass is tightly correlated with the stellar mass and velocity dispersion of the bulge. In a hierarchical universe, galaxies are built up through successive mergers of subgalactic units, a process that is accompanied by the amalgamation of bulges and the likely coalescence of galactocentric black holes. In these mergers, the beaming of gravitational radiation during the plunge phase of the black hole collision can impart a linear momentum kick or ‘gravitational recoil’ to the remnant. If large enough, this kick will eject the remnant from the galaxy entirely, and populate intergalactic space with wandering black holes. Using a semi-analytic model of galaxy formation, we investigate the effect of black hole ejections on the scatter of the relation between black hole and bulge mass. We find that while not being the dominant source of the measured scatter, they do provide a significant contribution and may be used to set a constraint, vkick≲ 500 km s−1, on the typical kick velocity, in agreement with values found from general relativistic calculations. Even for the more modest kick velocities implied by these calculations, we find that a substantial number of central black holes are ejected from the progenitors of present-day galaxies, giving rise to a population of wandering intrahalo and intergalactic black holes whose distribution we investigate in high-resolution N-body simulations of the Milk Way mass haloes. We find that intergalactic black holes make up only ∼2–3 per cent of the total galactic black hole mass but, within a halo, wandering black holes can contribute up to about half of the total black hole mass orbiting the central galaxy. Intrahalo black holes offer a natural explanation for the compact X-ray sources often seen near the centres of galaxies and for the hyperluminous non-central X-ray source in M82.

Binary Mergers and Growth of Black Holes in Dense Star Clusters

We model the dynamical evolution of primordial black holes (BHs) in dense star clusters using a simplified treatment of stellar dynamics in which the BHs are assumed to remain concentrated in an inner core, completely decoupled from the background stars. Dynamical interactions involving BH binaries are computed exactly and are generated according to a Monte Carlo prescription. Recoil and ejections lead to complete evaporation of the BH core on a timescale ~10^9 yr for typical globular cluster parameters. Orbital decay driven by gravitational radiation can make binaries merge and, in some cases, successive mergers can lead to significant BH growth. Our highly simplified treatment of the cluster dynamics allows us to study a large number of models and to compute statistical distributions of outcomes, such as the probability of massive BH growth and retention in a cluster. We find that, in most models, there is a significant probability (~20-80%) of BH growth with final masses > 100 M_{\sun}. In one case, a final BH formed with mass ~ 620 M_{\sun}. However, if the typical merger recoil speed (due to asymmetric emission of gravitational radiation) significantly exceeds the cluster escape speed, no growth ever occurs. Independent of the recoil speed, we find that BH-BH mergers enhanced by dynamical interactions in cluster cores present an important source of gravitational waves for ground--based laser interferometers. Under optimistic conditions, the total rate of detections by Advanced LIGO, could be as high as a few tens of events per year from inspiraling BHs from clusters.