Dynamics of Galaxy Cores and Supermassive Black Holes
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Dynamics and Evolution of Supermassive Black Holes in Merging Galaxies
Dynamics and Evolution of Supermassive Black Holes in Merging Galaxies Fazeel Mahmood Khan Astronomisches Rechen-Institut Zentrum f¨urAstronomie der Universit¨atHeidelberg Heidelberg 2011 Cover picture: Gemini image of NGC 5426-27 (Arp 271). Dissertation submitted to the Combined Faculties for the Natural Sciences and for Mathematics of the Ruperto-Carola University of Heidelberg, Germany for the degree of Doctor of Natural Sciences Put forward by Fazeel Mahmood Khan Born in: Azad Kashmir, Pakistan Oral examination: January 25, 2012 Dynamics and Evolution of Supermassive Black Holes in Merging Galaxies Referees: PD Dr. Andreas Just Prof. Dr. Volker Springel Abstract Supermassive black holes (SMBHs) are ubiquitous in galaxy centers and are correlated with their hosts in fundamental ways, suggesting an intimate link between SMBH and galaxy evolution. In the paradigm of hierarchical galaxy formation this correlation demands prompt coalescence of SMBH binaries, presumably due to dynamical friction, interaction of stars and gas with the binary and finally due to gravitational wave emission. If they are able to coalesce in less than a Hubble time, SMBH binaries will be a promising source of gravitational waves for gravitational wave detectors. However, it has been suggested that SMBH binaries may stall at a separation of 1 parsec. This stalling is sometimes referred to as the \Final Parsec Problem (FPP)". This study uses N-body simulations to test an improved formula for the orbital decay of SMBHs due to dynamical friction. Using a large set of N-body simulations, we show that the FPP does not occur in galaxies formed via mergers. The non spherical shape of the merger remnants ensures a constant supply of stars for the binary to interact with. -
Mass Deficits, Stalling Radii, and the Merger Histories of Elliptical Galaxies David Merritt Rochester Institute of Technology
Rochester Institute of Technology RIT Scholar Works Articles 5-22-2006 Mass Deficits, Stalling Radii, and the Merger Histories of Elliptical Galaxies David Merritt Rochester Institute of Technology Follow this and additional works at: http://scholarworks.rit.edu/article Recommended Citation David Merritt 2006 ApJ 648 976 This Article is brought to you for free and open access by RIT Scholar Works. It has been accepted for inclusion in Articles by an authorized administrator of RIT Scholar Works. For more information, please contact [email protected]. DRAFT VERSION FEBRUARY 5, 2008 Preprint typeset using LATEX style emulateapj v. 10/09/06 MASS DEFICITS, STALLING RADII, AND THE MERGER HISTORIES OF ELLIPTICAL GALAXIES DAVID MERRITT Department of Physics, Rochester Institute of Technology, Rochester, NY 14623 Draft version February 5, 2008 Abstract A binary supermassive black hole leaves an imprint on a galactic nucleus in the form of a “mass deficit,” a decrease in the mass of the nucleus due to ejection of stars by the binary. The magnitude of the mass deficit is in principle related to the galaxy’s merger history, but the relation has never been quantified. Here, high- accuracy N-body simulations are used to calibrate this relation. Mass deficits are shown to be Mde f ≈ 0.5M12, with M12 the total mass of the binary; the coefficient in this relation depends only weakly on M2/M1 or on the galaxy’s pre-existing density profile. Hence, after N mergers, Mde f ≈ 0.5N M• with M• the final (current) black hole mass. When compared with observed mass deficits, this result implies 1 ∼< N ∼< 3, in accord with hierarchical galaxy formation models. -
The Coevolution of Nuclear Star Clusters, Massive
The Astrophysical Journal, 812:72 (24pp), 2015 October 10 doi:10.1088/0004-637X/812/1/72 © 2015. The American Astronomical Society. All rights reserved. THE COEVOLUTION OF NUCLEAR STAR CLUSTERS, MASSIVE BLACK HOLES, AND THEIR HOST GALAXIES Fabio Antonini1, Enrico Barausse2,3, and Joseph Silk2,3,4,5 1 Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA) and Department of Physics and Astrophysics, Northwestern University, Evanston, IL 60208, USA 2 Sorbonne Universités, UPMC Univ Paris 06, UMR 7095, Institut d’Astrophysique de Paris, F-75014, Paris, France 3 CNRS, UMR 7095, Institut d’Astrophysique de Paris, F-75014, Paris, France 4 Laboratoire AIM-Paris-Saclay, CEA/DSM/IRFU, CNRS, Universite Paris Diderot, F-91191 Gif-sur-Yvette, France 5 Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218, USA Received 2015 June 5; accepted 2015 September 3; published 2015 October 8 ABSTRACT Studying how nuclear star clusters (NSCs) form and how they are related to the growth of the central massive black holes (MBHs) and their host galaxies is fundamental for our understanding of the evolution of galaxies and the processes that have shaped their central structures. We present the results of a semi-analytical galaxy formation model that follows the evolution of dark matter halos along merger trees, as well as that of the baryonic components. This model allows us to study the evolution of NSCs in a cosmological context, by taking into account the growth of NSCs due to both dynamical-friction-driven migration of stellar clusters and star formation triggered by infalling gas, while also accounting for dynamical heating from (binary) MBHs. -
Central Massive Objects: the Stellar Nuclei – Black Hole Connection
Astronomical News Report on the ESO Workshop Central Massive Objects: The Stellar Nuclei – Black Hole Connection held at ESO Garching, Germany, 22–25 June 2010 Nadine Neumayer1 Eric Emsellem1 1 ESO An overview of the ESO workshop on black holes and nuclear star clusters is presented. The meeting reviewed the status of our observational and the- oretical understanding of central mas- sive objects, as well as the search for intermediate mass black holes in globu- lar clusters. There will be no published proceedings, but presentations are available at http://www.eso.org/sci/ meetings/cmo2010/program.html. This workshop brought together a broad international audience in the combined fields of galaxy nuclei, nuclear star clus ters and supermassive black holes, to confront stateofthe art observations with cuttingedge models. Around a hundred participants from Europe, North and South America, as well as East Asia and Figure 1. Workshop participants assembled outside made up of several populations of stars. Australia gathered for a threeday meet ESO Headquarters in Garching. The existence of very young O and WR ing held at ESO Headquarters in Garching, stars in the central few arcseconds Germany (see Figure 1). The sessions around the black hole is puzzling. The were of very high quality, with many very – Are intermediate mass black holes currently favoured solution to this paradox lively, interesting and fruitful discussions. formed in nuclear clusters/globular of youth is in situ star formation in infalling All talks can be found online on the web clusters? gas clouds. This view is also supported page of the workshop1. -
Stellar Mass Function in the Field
Professor David Carter (PI) Liverpool John Moores University UK Dr Habib G. Khosroshahi Liverpool John Moores University UK Mr Mustapha Mouhcine Liverpool John Moores University UK Ms Susan M. Percival Liverpool John Moores University UK Dr Harry C. Ferguson (USA PI) Space Telescope Science Institute USA/MD Dr Paul Goudfrooij Space Telescope Science Institute USA/MD Dr Terry Bridges Queen's University Canada Dr Thomas H. Puzia Dominion Astrophysical Observatory Canada Dr Carlos del Burgo Dublin Institute For Advanced Studies Ireland Dr Bryan Miller Gemini Observatory, Southern Operations Chile Dr Bianca Poggianti INAF - Osservatorio Astronomico di Padova Italy Dr Alfonso Aguerri Instituto de Astrofisica de Canarias Spain Dr Marc Balcells Instituto de Astrofisica de Canarias Spain Mr Derek Hammer Johns Hopkins University USA/MD Dr Reynier F. Peletier Kapteyn Astronomical Institute Netherlands Prof. Edwin Valentijn Kapteyn Astronomical Institute Netherlands Dr Gijs Verdoes Kleijn Kapteyn Astronomical Institute Netherlands Dr Peter Erwin Max-Planck-Insitute for Extraterrestrial Physics Germany Dr Ann Hornschemeier NASA Goddard Space Flight Center USA/MD Dr Yutaka Komiyama National Astronomical Observatory of Japan Japan Dr Masafumi Yagi National Astronomical Observatory of Japan Japan Dr Jennifer Lotz National Optical Astronomy Observatories, AURA USA/AZ National Radio Astronomy Observatory, Dr Neal A. Miller USA/VA and Johns Hopkins University Dr Eric W. Peng Peking University China Dr Dan Batcheldor Rochester Institute of Technology USA/NY Prof. David Merritt Rochester Institute of Technology USA/NY Dr Ronald O. Marzke San Francisco State University USA/CA Dr Alister W. Graham Swinburne University of Technology Australia Dr Helmut Jerjen The Australian National University Australia Dr Avon P. -
Accretion Onto a Quintessence Contaminated Rotating Black Hole : Violating the Lower Limit for Eta Over S Arxiv:1911.08304V2 [G
Accretion onto a Quintessence Contaminated Rotating Black Hole : Violating the Lower Limit for Eta over s Ritabrata Biswas 1 Promila Biswas 3 Parthajit Roy 2∗ 1;3 Department of Mathematics, The University of Burdwan Golapbag Academic Complex, City:Burdwan-713104, Dist: Purba Bardhaman, State: West Bengal, India 1e-mail: [email protected] 3e-mail: [email protected] 2Department of Computer Science, The University of Burdwan City:Burdwan-713104, Dist: Purba Bardhaman, State: West Bengal, India e-mail: [email protected] ∗ Abstract Viscous accretion flow around a rotating supermassive black hole sitting in a quintessence tub is studied in this article. To introduce such a dark energy contaminated black hole's gravitational force, a new pseudo-Newtonian potential is used. This pseudo-Newtonian force can be calculated if we know the distance from the black hole's center, spin of the black hole and equation of state of the quintessence inside which the black hole is considered to lie. This force helps us to avoid complicated nonlinearity of general relativistic field equations. Transonic, viscous, continuous and Keplerian flow is assumed to take place. Fluid speed, sonic speed profile and specific angular momentum to Keplerian angular momentum ratio are found out for different values of spin parameter and arXiv:1911.08304v2 [gr-qc] 2 Mar 2021 quintessence parameter. Density variation is built and tallied with observations. Shear viscosity to entropy density ratio is constructed for our model and a comparison with theoretical lower limit is done. Keywords: Accretion Disc, Viscosity, Quintessence, Supermassive Black Holes, Shear Viscosity to entropy ratio PACS: 97.10.Gz; 51.20.+d; 51.30.+i; 95.36.+x; 97.60.25 1 Introduction Since 1998, despite the propositions of different conceptual models, we were not really able to construct a hundred percent correct theoretical support to the observations of late time cosmic acceleration. -
The Formation of Extremely Diffuse Galaxy Cores by Merging Supermassive Black Holes
The Astrophysical Journal, 864:113 (20pp), 2018 September 10 https://doi.org/10.3847/1538-4357/aada47 © 2018. The American Astronomical Society. All rights reserved. The Formation of Extremely Diffuse Galaxy Cores by Merging Supermassive Black Holes Antti Rantala1 , Peter H. Johansson1 , Thorsten Naab2 , Jens Thomas3 , and Matteo Frigo2 1 Department of Physics, University of Helsinki, Gustaf Hällströmin katu 2a, FI-00560 Helsinki, Finland; antti.rantala@helsinki.fi 2 Max-Planck-Insitut für Astrophysik, Karl-Schwarzchild-Str. 1, D-85748, Garching, Germany 3 Max-Planck-Institut für Extraterrestriche Physik, Giessenbach-Str. 1, D-85741, Garching, Germany Received 2018 May 25; revised 2018 August 9; accepted 2018 August 12; published 2018 September 5 Abstract 10 Given its velocity dispersion, the early-type galaxy NGC 1600 has an unusually massive (M• = 1.7 × 10 Me) central supermassive black hole (SMBH) surrounded by a large core (rb = 0.7 kpc) with a tangentially biased stellar distribution. We present high-resolution equal-mass merger simulations including SMBHs to study the formation of such systems. The structural parameters of the progenitor ellipticals were chosen to produce merger remnants resembling NGC 1600. We test initial stellar density slopes of ρ∝r−1 and ρ∝r−3/2 and vary 8 9 the initial SMBH masses from 8.5×10 to 8.5×10 Me. With increasing SMBH mass, the merger remnants show a systematic decrease in central surface brightness, an increasing core size, and an increasingly tangentially biased central velocity anisotropy. Two-dimensional kinematic maps reveal decoupled, rotating core regions for the most massive SMBHs. The stellar cores form rapidly as the SMBHs become bound, while the velocity anisotropy develops more slowly after the SMBH binaries become hard. -
The Role of Flyby Interactions in Shaping Galaxy Evolution By
The Role of Flyby Interactions in Shaping Galaxy Evolution By Meagan Lang Dissertation Submitted to the Faculty of the Graduate School of Vanderbilt University in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY in Physics August 2015 Nashville, Tennessee Approved: Prof. Kelly Holley-Bockelmann Prof. Andreas Berlind Prof. David A. Weintraub Prof. Kirill Bolotin I dedicate this thesis to My Family, For their endless support and encouragement, and My Friends, For making me smile, giving me perspective, and making Nashville a home. ii ACKNOWLEDGMENTS This work was made possible by financial support from the Vanderbilt Provost Grad- uate Fellowship, National Science Foundation Graduate Research Fellowship, and Extreme Science and Engineering Discovery Environment computing allocation. I am grateful to the Vanderbilt astronomy group for providing such a diverse and welcoming community, fostering my growth as both a scientist and a person. I want to thank Dr. Manodeep Sinha in particular for his patience and guidance. Our daily discussions challenged me to explore unfamiliar concepts and strengthen my research ideas. I would also like to thank my Dissertation Committee for their invaluable feedback. I am especially grateful to Dr. Kelly Holley-Bockelmann, my committee chairperson, for her contribution to my professional development as my advisor and mentor. She encouraged me to pursue new lines of research and instilled in me the need to always be aware of the larger picture. I also want to thank the friends I have made both inside and outside the astronomy community during my journey to this point. They have made me a better person, given me the strength to take on new challenges, and made me feel at home even when my family is far away. -
The Star Clusters Young & Old Newsletter
SCYON The Star Clusters Young & Old Newsletter edited by Holger Baumgardt, Ernst Paunzen and Pavel Kroupa SCYON can be found at URL: http://astro.u-strasbg.fr/scyon SCYONIssueNo.31 11December2006 EDITORIAL Here is the 31st issue of the SCYON newsletter. The current issue contains 35 abstracts, an an- nouncement for a new, parallel N-body code and announcements for conferences in Italy, Germany and Armenia. It also contains job advertisements for postdoctoral and tenure track positions from Rochester Institute of Technology. We wish everybody a merry holiday season and a happy new year 2007 and thank those who sent us their contributions. Holger Baumgardt, Ernst Paunzen and Pavel Kroupa ................................................... ................................................. CONTENTS Editorial .......................................... ...............................................1 SCYON policy ........................................ ...........................................2 Mirror sites ........................................ ..............................................2 Abstract from/submitted to REFEREED JOURNALS ........... ................................3 1. Star Forming Regions ............................... ........................................3 2. Embedded Clusters................................. .........................................7 3. Galactic Center Clusters........................... ..........................................9 4. Galactic Open Clusters............................. ........................................10 -
Long-Term Evolution of Massive Black Hole Binaries. III. Binary Evolution in Collisional Nuclei David Merritt Rochester Institute of Technology
Rochester Institute of Technology RIT Scholar Works Articles 12-10-2007 Long-term evolution of Massive Black Hole Binaries. III. Binary Evolution in Collisional Nuclei David Merritt Rochester Institute of Technology Seppo Mikkola Turku University Observatory Andras Szell Rochester Institute of Technology Follow this and additional works at: http://scholarworks.rit.edu/article Recommended Citation David Merritt te al 2007 ApJ 671 53 https://doi.org/10.1086/522691 This Article is brought to you for free and open access by RIT Scholar Works. It has been accepted for inclusion in Articles by an authorized administrator of RIT Scholar Works. For more information, please contact [email protected]. DRAFT VERSION FEBRUARY 1, 2008 Preprint typeset using LATEX style emulateapj v. 10/09/06 LONG-TERM EVOLUTION OF MASSIVE BLACK HOLE BINARIES. III. BINARY EVOLUTION IN COLLISIONAL NUCLEI DAVID MERRITT Department of Physics, 85 Lomb Memorial Drive, Rochester Institute of Technology, Rochester, NY 14623 and Center for Computational Relativity and Gravitation, School of Mathematical Sciences, 78 Lomb Memorial Drive, Rochester Institute of Technology, Rochester, NY 14623 SEPPO MIKKOLA Turku University Observatory, Tuorla, 21500 Piikkiö, Finland ANDRAS SZELL Department of Physics, 85 Lomb Memorial Drive, Rochester Institute of Technology, Rochester, NY 14623 Draft version February 1, 2008 Abstract In galactic nuclei with sufficiently short relaxation times, binary supermassive black holes can evolve beyond their stalling radii via continued interaction with stars. We study this “collisional” evolutionary regime using both fully self-consistent N-body integrations and approximate Fokker-Planck models. The N-body integra- tions employ particle numbers up to 0.26 106 and a direct-summation potential solver; close interactions involving the binary are treated using a new× implementation of the Mikkola-Aarseth chain regularization al- gorithm. -
Galactic Nuclei
Relativity, torque and spin PROFESSOR DAVID MERRITT DAVID PROFESSOR Professor David Merritt explains his interest in astrophysics and the focus of his current research. Describing the improvements made to the computational algorithms, he highlights the importance of taking into account the effects of relativity in these calculations sometimes reveal modes of behaviour that can be inefficient when applied to galactic are strikingly simple yet totally unexpected. nuclei, because motion is dominated by the presence of the SBH. A star or stellar remnant Your current project focuses on the dynamical will complete millions of orbits around evolution of dense clusters of stars and the SBH before coming close enough to stellar remnants around supermassive black another star to be perturbed, but it is those holes (SBHs) at the centre of galaxies. Why is perturbations that are driving the collective this important? evolution. The computer code needs to follow the unperturbed orbit about the SBH with A star like the Sun would be tidally torn apart extremely high precision: otherwise the effects if it came sufficiently close to an SBH. Partly of the small perturbations will be swamped by because of tidal effects, the only objects numerical errors. that we expect to find very near an SBH are ‘compact remnants’: neutron stars and Why is it important to take into account stellar-mass black holes, the dense leftovers the effects of relativity when simulating the from the evolution of massive stars. These evolution of nuclear star clusters? remnants can interact through ‘gravitational encounters’: close passages that exchange One insight that comes from my group’s research energy and gradually change orbits. -
Extracting the Gravitational Recoil from Black Hole Merger Signals
Extracting the Gravitational Recoil from Black Hole Merger Signals Vijay Varma,1, ∗ Maximiliano Isi,2, † and Sylvia Biscoveanu2, ‡ 1TAPIR 350-17, California Institute of Technology, 1200 E California Boulevard, Pasadena, CA 91125, USA 2LIGO Laboratory, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA (Dated: March 11, 2020) Gravitational waves carry energy, angular momentum, and linear momentum. In generic binary black hole mergers, the loss of linear momentum imparts a recoil velocity, or a “kick”, to the remnant black hole. We exploit recent advances in gravitational waveform and remnant black hole modeling to extract information about the kick from the gravitational wave signal. Kick measurements such as these are astrophysically valuable, enabling independent constraints on the rate of second-generation mergers. Further, we show that kicks must be factored into future ringdown tests of general relativity with third-generation gravitational wave detectors to avoid systematic biases. We find that, although little information can be gained about the kick for existing gravitational wave events, interesting measurements will soon become possible as detectors improve. We show that, once LIGO and Virgo reach their design sensitivities, we will reliably extract the kick velocity for generically precessing binaries—including the so-called superkicks, reaching up to 5000 km/s. Introduction.— As existing gravitational wave (GW) de- galactic centers. The remnant BH can be significantly tectors, Advanced LIGO [1] and Virgo [2], approach their displaced or ejected [31, 32], impacting the galaxy’s evo- design sensitivities, they continue to open up unprece- lution [33–35], and event rates [36] for the future LISA dented avenues for studying the astrophysics of black mission [37].