Galaxy Mergers and Interactions at High Redshift [PDF]
, 2006 In this review we discuss the evidence for galaxy interactions and mergers in the distant universe and the role of mergers in forming galaxies. Observations show that the fraction of massive (M> M_*) galaxies involved in major mergers is roughly 5-10% at z~1.
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Evidence for non-merger co-evolution of galaxies and their supermassive black holes [PDF]
, 2022 Recent observational and theoretical studies have suggested that supermassive black holes (SMBHs) grow mostly through non-merger (`secular') processes. Since galaxy mergers lead to dynamical bulge growth, the only way to observationally isolate non-merger growth is to study galaxies with low bulge-to-total mass ratio (e.g. B/T < 10%).
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Massive Black Hole Binaries: Dynamical Evolution and Observational Signatures
Advances in Astronomy, 2012 The study of the dynamical evolution of massive black hole pairs in mergers is crucial in the context of a hierarchical galaxy formation scenario. The timescales for the formation and the coalescence of black hole binaries are still poorly constrained ...
M. Dotti, A. Sesana, R. Decarli
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The Origin of the Consistent Planetary Nebula Luminosity Function Bright-end Cutoff
The Astrophysical Journal, 2023 The [O iii ] 5007 Å line is typically the brightest line in planetary nebula (PN) spectra. Observations show that the brightest [O iii ] 5007 Å PN in a galaxy—the planetary nebula luminosity function (PNLF) bright-end cutoff—is surprisingly independent ...
Philippe Z. Yao, Eliot Quataert
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Spatially Offset Active Galactic Nuclei III: Discovery of Late-Stage Galaxy Mergers with The Hubble Space Telescope [PDF]
, 2018 Galaxy pairs with separations of only a few kpc represent important stages in the merger-driven growth of supermassive black holes (SMBHs). However, such mergers are difficult to identify observationally due to the correspondingly small angular scales.
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Interacting galaxies in the IllustrisTNG simulations -- IV: Enhanced Supermassive Black Hole Accretion Rates in Post-Merger Galaxies [PDF]
, 2022 We present an analysis of the instantaneous supermassive black hole (SMBH) accretion rates in a collection of 1563 post-merger galaxies drawn from the IllustrisTNG simulation. Our sample consists of galaxies that have experienced a merger in the last simulation snapshot (within ~160 Myrs of coalescence) in the redshift range 0
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The Open Journal of Astrophysics, 2023 Despite the importance of Active Galactic Nuclei (AGN) in galaxy evolution, the mechanisms that fuel AGN activity remain poorly understood. Theoretical models suggest that major mergers of galaxies contribute strongly to AGN fuelling, particularly at ...
Carolin Villforth
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Method for Determining AGN Accretion Phase in Field Galaxies [PDF]
, 2016 Recent observations of AGN activity in massive galaxies (log Mstar / Msun > 10.4) show that: 1) at z < 1, AGN-hosting galaxies do not show enhanced merger signatures compared to normal galaxies, 2) also at z < 1, most AGNs are hosted by quiescent galaxies; and 3) at z > 1, percentage of AGNs in star forming galaxies increases and becomes comparable to ...
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Galaxy Merger Statistics and Inferred Bulge-to-Disk Ratios in Cosmological SPH Simulations [PDF]
Astrophys.J.647:763-772,2006, 2005 We construct merger trees for galaxies identified in a cosmological hydrodynamical simulation and use them to characterize predicted merger rates as a function of redshift, galaxy mass, and merger mass ratio. At z=0.3, we find a mean rate of 0.054 mergers per galaxy per Gyr above a 1:2 mass ratio threshold for massive galaxies (baryonic mass above 6 ...
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The Structures of Distant Galaxies - IV: A New Empirical Measurement of the Time-Scale for Galaxy Mergers - Implications for the Merger History [PDF]
, 2009 Understanding the role of mergers in galaxy formation is one of the most outstanding problems in extragalactic astronomy. While we now have an idea for how the merger fraction evolves at redshifts z < 3, converting this merger fraction into merger rates, and therefore how many mergers an average galaxy undergoes during its history, is still uncertain ...
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