Untitled

Raig, A.; Salvador-Solé, E.; González-Casado, Guillermo

doi:10.1023/a:1002175525448

Cited by 4 publications

(9 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The rate at which haloes of mass M f form through all mergers at time t is The probability distribution function (PDF) of formation times of haloes with mass M 0 at time t 0 is Given a formation time t f and corresponding mass M ( t f ) along the past accretion track of M 0 , the mass of the larger progenitor M 1 is distributed according to where By choosing formation times and progenitor masses randomly according to and , we capture the stochasticity of the intervals between mergers above Δ m , but treat merging below this threshold only in the mean. See Manrique & Salavador‐Sole (1996), Salvador‐Sole et al (1998) and Raig, Gonzalez‐Casado & Salvador‐Sole (2001) for further details and derivations of and . Fig.…”

Section: Model and Methodsmentioning

confidence: 99%

Dynamics of triple black hole systems in hierarchically merging massive galaxies

Hoffman

Loeb

2007

Monthly Notices of the Royal Astronomical Society

168

167

View full text Add to dashboard Cite

Galaxies with stellar bulges are generically observed to host supermassive black holes (SMBHs). The hierarchical merging of galaxies should therefore lead to the formation of SMBH binaries. Merging of old massive galaxies with little gas promotes the formation of low‐density nuclei where SMBH binaries are expected to survive over long times. If the binary lifetime exceeds the typical time between mergers, then triple black hole (BH) systems may form. We study the statistics of close triple SMBH encounters in galactic nuclei by computing a series of three‐body orbits with physically motivated initial conditions appropriate for giant elliptical galaxies. Our simulations include a smooth background potential consisting of a stellar bulge plus a dark matter halo, drag forces due to gravitational radiation and dynamical friction on the stars and dark matter, and a simple model of the time evolution of the inner density profile under heating and mass ejection by the SMBHs. We find that the binary pair coalesces as a result of repeated close encounters in ∼85 per cent of our runs, and in ∼15 per cent of cases a new eccentric binary forms from the third SMBH and binary remnant and coalesces during the run time. In about 40 per cent of the runs the lightest BH is left wandering through the galactic halo or escapes the galaxy altogether, but escape of all three SMBHs is exceedingly rare. The triple systems typically scour out cores with mass deficits ∼one–two times their total mass, which can help to account for the large cores observed in some massive elliptical galaxies, such as M87. The high coalescence rate, prevalence of very high‐eccentricity orbits, and gravitational radiation ‘spikes’ during close encounters in our runs, may provide interesting signals for the future Laser Interferometer Space Antenna (LISA).

show abstract

Section: Model and Methodsmentioning

confidence: 99%

Dynamics of triple black hole systems in hierarchically merging massive galaxies

Hoffman

Loeb

2007

Monthly Notices of the Royal Astronomical Society

168

167

View full text Add to dashboard Cite

show abstract

“…These are the merger events we refer to here as MMs. As shown by Raig et al (2001), MMs are essentially binary and involve similarly massive haloes. More specifically, the halo internal structure found in high‐resolution N ‐body simulations (Navarro, Frenk & White 1997) is recovered (Manrique et al 2003) provided Δ m ∼ 0.5.…”

Section: Halo Major Merger Ratementioning

confidence: 97%

“…The modified Press–Schechter (MPS) model developed by Salvador‐Solé, Solanes & Manrique (1998) and Raig, González‐Casado & Salvador‐Solé (1998), Raig et al (2001) is a variant of the extended PS model (Bond et al 1991; Bower 1991; Lacey & Cole 1993) that provides an unambiguous definition of the halo formation and destruction times and other quantities, such as the halo MM rate, not available in the original extended PS model.…”

Section: Halo Major Merger Ratementioning

confidence: 99%

“…The associated formation rate, R form , defined again as a transition rate, is then equal to the MM rate given by divided by f ( M H , t ) d M H . The goodness of the preceding expressions has been checked against N ‐body simulations by Raig et al (2001).…”

Section: Halo Major Merger Ratementioning

confidence: 99%

“…In particular, accurate analytical expressions for the halo MM rate are available (e.g. Percival, Miller & Peacock 2000; Raig, González‐Casado & Salvador‐Solé 2001) that can be easily implemented. The aim of the present paper is to build such a complete, physically motivated model and check the validity of the previous scenario by comparing the predicted luminosity function of quasars (QLF) with the most recent publicly available observations.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Major mergers of haloes, the growth of massive black holes and the evolving luminosity function of quasars

Hatziminaoglou¹,

Mathez²,

Solanes³

et al. 2003

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

We construct a physically motivated analytical model for the quasar luminosity function, based on the joint star formation and feeding of massive black holes suggested by the observed correlation between the black hole mass and the stellar mass of the hosting spheroids. The parallel growth of massive black holes and host galaxies is assumed to be triggered by major mergers of haloes. The halo major merger rate is computed within the framework of the extended Press–Schechter model. The evolution of black holes on cosmological time‐scales is achieved by the integration of the governing set of differential equations, established from a few reasonable assumptions that account for the distinct (Eddington‐limited or supply‐limited) accretion regimes. Finally, the typical light curves of the reactivated quasars are obtained under the assumption that, in such accretion episodes, the fall of matter on to the black hole is achieved in a self‐regulated stationary way. The predicted quasar luminosity function is compared with the luminosity functions of the 2dF quasi‐stellar object sample and other, higher‐redshift data. We find good agreement in all cases, except for z < 1 where the basic assumption of our model is likely to break down.

show abstract

Leaving the Dark Ages With Amiga

Manrique¹,

Salvador-Solé²,

Juan³

et al. 2015

ApJS

View full text Add to dashboard Cite

We present an Analytic Model of Intergalactic-medium and GAlaxy evolution since the dark ages. AMIGA is in the spirit of the popular semi-analytic models of galaxy formation, although it does not use halo merger trees but interpolates halo properties in grids that are progressively built. This strategy is less memory-demanding and allows one to start the modeling at redshifts high enough and halo masses low enough to have trivial boundary conditions. The number of free parameters is minimized by making the causal connection between physical processes usually treated as independent from each other, which leads to more reliable predictions. But the strongest points of AMIGA are: i) the inclusion of molecular cooling and metal-poor, population III (Pop III) stars, with the most dramatic feedback, and ii) the accurate follow-up of the temperature and volume filling factor of neutral, singly, and doubly ionized regions, taking into account the distinct halo mass functions in those environments. We find the following general results. Massive Pop III stars determine the IGM metallicity and temperature, and the growth of spheroids and disks is self-regulated by that of massive black holes developed from the remnants of those stars. Yet, the properties of normal galaxies and active galactic nuclei appear to be quite insensitive to Pop III star properties owing to the much higher yield of ordinary stars compared to Pop III stars and the dramatic growth of MBHs when normal galaxies begin to develop, which cause the memory loss of the initial conditions. Subject headings: galaxies -galaxies: formation -dark matter -intergalactic medium 1 Even though current simulations start at z > ∼ 100, convergence of galaxy properties is only found up to z ∼ 7 for the most favorable case of relatively low resolutions (Schaye et al. 2010).

show abstract

Untitled

Cited by 4 publications

References 4 publications

Dynamics of triple black hole systems in hierarchically merging massive galaxies

Dynamics of triple black hole systems in hierarchically merging massive galaxies

Major mergers of haloes, the growth of massive black holes and the evolving luminosity function of quasars

Leaving the Dark Ages With Amiga

Contact Info

Product

Resources

About