Triplets of supermassive black holes: Astrophysics, Gravitational Waves and Detection (2009)
Amaro-Seoane, Pau, Sesana, Alberto, Hoffman, Loren, Benacquista, Matthew, Eichhorn, Christoph, Makino, Junichiro, ...
Supermassive black holes (SMBHs) found in the centers of many galaxies have been recognized to play a fundamental active role in the cosmological structure formation process. In hierarchical...
Marc Hemsendorf, Emil Khalisi, Chingis Omarov, Rainer Spurzem, Dietrich Wolf, Gernot Münster, ...
published in
Formation and Evolution of Black Holes in Galactic Nuclei and Star Clusters (2009)
R. Spurzem, P. Berczik, I. Berentzen, D. Merritt, M. Preto, ...
published in
Relaxation Processes and Black Holes in Star Clusters andGalactic Nuclei (2009)
Marc Hemsendorf, Emil Khalisi, Chingis Omarov, Rainer Spurzem
We use high-precision direct N-body integration to study questions of the thermodynamic be-haviour of dense stellar systems and of the state of dense stellar systems interacting with binary black...
Amaro-Seoane, Pau, Eichhorn, Christoph, Porter, Edward K., Spurzem, Rainer
The dynamical evolution of binaries of intermediate-massive black holes (IMBHs, massive black holes with a mass ranging between $10^2$ and $10^4 M_{\odot}$) in stellar clusters has recently received...
On the dissolution of star clusters in the Galactic centre. I. Circular orbits (2009)
Ernst, Andreas, Just, Andreas, Spurzem, Rainer
We present N-body simulations of dissolving star clusters close to galactic centres. For this purpose, we developed a new N-body program called nbody6gc based on Aarseth's series of N-body codes. We...
Binary Black Hole Merger in Galactic Nuclei: Post-Newtonian Simulations (2008)
Berentzen, Ingo, Preto, Miguel, Berczik, Peter, Merritt, David, Spurzem, Rainer
This paper studies the formation and evolution of binary supermassive black holes (SMBHs) in rotating galactic nuclei, focusing on the role of stellar dynamics. We present the first N-body...
Binary black hole merger in galactic nuclei: Post-newtonian simulations (2008)
Bergentzen, Ingo, Preto, Miguel, Berczik, Peter, Merritt, David, Spurzem, Rainer
Archived in arXiv:0812.2756 v1 De 15, 2008
Post-Newtonian simulations of super-massive black hole binaries in galactic nuclei (2008)
Berentzen, Ingo, Preto, Miguel, Merritt, David, Spurzem, Rainer
Also archived in arXiv:0810.5253 v1 Oct 29 2008. Publisher version can be found here: http://www3.interscience.wiley.com/journal/121536915/issue
Merger of Massive Black Holes using N-Body Simulations with Post-Newtonian Corrections (2008)
Preto, Miguel, Berentzen, Ingo, Berczik, Peter, Merritt, David, Spurzem, Rainer
We present preliminary results from self-consistent, high resolution direct {\it N}-body simulations of massive black hole binaries in mergers of galactic nuclei. The dynamics of the black hole...
Merger of Massive Black holes using n-body simulations with post-newtonian corrections (2008)
Preto, Miguel, Berentzen, Ingo, Berczik, Peter, Merritt, David, Spurzem, Rainer
Proceedings from the 7th LISA Symposium, Barcelona, 16-20 June 2008
Double Black Holes in Galactic Nuclei – Do they Merge or not? (2008)
Marc Hemsendorf, Rainer Spurzem, Steinn Sigurdsson, Marc Hemsendorf, Rainer Spurzem, Steinn Sigurdsson
Permission to make digital or hard copies of portions of this work for personal or classroom use is granted provided that the copies are not made or distributed for profit or commercial advantage and...
Distributed File Management in AstroGrid-D (2008)
Breitling, Frank, Brüsemeister, Thomas, Carlson, Art, Engel, Robert, Enke, Harry, Högqvist, Mikael, ...
Dynamical evolution of rotating stellar systems: I. Pre-collapse, equal mass system (2007)
Christian Einsel And, Christian Einsel, Rainer Spurzem
The influence of rotation on the dynamical evolution of collisional stellar systems is investigated by solving the orbit-averaged Fokker-Planck equation in (E; J z )-space. We find that large amounts...
Dynamical Simulations: Methods And Comparisons (2007)
D. C. Heggie, Mirek Giersz, Rainer Spurzem
this paper, Sect. 4. 4. Fokker-Planck models remain the principal tool for studying the dynamical evolution of both individual clusters (e.g. Sosin & King 1997) and the cluster system as a whole...
Double Black Holes in Galactic Nuclei-- Do they Merge or not? (2007)
Horst Rollnik, Dietrich Wolf (editor, Marc Hemsendorf, Marc Hemsendorf, Rainer Spurzem, Rainer Spurzem, ...
2002 by John von Neumann Institute for Computing Permission to make digital or hard copies of portions of this work for personal or classroom use is granted provided that the copies are not made or...
Escape from the vicinity of fractal basin boundaries of a star cluster (2007)
Ernst, Andreas, Just, Andreas, Spurzem, Rainer, Porth, Oliver
The dissolution process of star clusters is rather intricate for theory. We investigate it in the context of chaotic dynamics. We use the simple Plummer model for the gravitational field of a star...
Kim, Eunhyeuk, Yoon, Ilsang, Lee, Hyung Mok, Spurzem, Rainer
We have carried out N-body simulations for rotating star clusters with equal mass and compared the results with Fokker-Planck models. These two different approaches are found to produce fairly...
NBODY meets stellar population - The HYDE-PARC Project (2007)
Borch, Andrea, Spurzem, Rainer, Hurley, Jarrod
N-body simulations give us a rough idea of how the shape of a simulated object appears in three-dimensional space. From an observational point of view this may give us a misleading picture. The faint...
N-body Models of Rotating Globular Clusters (2007)
Ernst, Andreas, Glaschke, Patrick, Fiestas, Jose, Just, Andreas, Spurzem, Rainer
We have studied the dynamical evolution of rotating globular clusters with direct $N$-body models. Our initial models are rotating King models; we obtained results for both equal-mass systems and...
Khalisi, Emil, Amaro-Seoane, Pau, Spurzem, Rainer
We address the dynamical evolution of an isolated self--gravitating system with two stellar mass groups. We vary the individual ratio of the heavy to light bodies, $\mu$ from 1.25 to 50 and alter...
Division VII: galactic system (2007)
Whitelock, Patricia, Sarajedini, Ata, Gerhard, Ortwin, Giersz, Mirek, Meylan, Georges, Nordström, Birgitta, ...
Performance Analysis of Direct N-Body Algorithms on Special-Purpose Supercomputers (2006)
Harfst, Stefan, Gualandris, Alessia, Merritt, David, Spurzem, Rainer, Zwart, Simon Portegies, Berczik, Peter
Direct-summation N-body algorithms compute the gravitational interaction between stars in an exact way and have a computational complexity of O(N^2). Performance can be greatly enhanced via the use...
Efficient merger of Binary Supermassive Black Holes in Non-Axisymmetric Galaxies (2006)
Berczik, Peter, Merritt, David, Spurzem, Rainer, Bischof, Hans-Peter
Also archived in: arXiv:astro-ph/0601698 v1 Jan 30 2006
Khalisi, Emil, Amaro-Seoane, Pau, Spurzem, Rainer
We address the dynamical evolution of an isolated self--gravitating system with two stellar mass groups. We vary the individual ratio of the heavy to light bodies, $\mu$ from 1.25 to 50 and alter...
Dynamics of compact objects clusters: A post-Newtonian study (2006)
Kupi, Gabor, Amaro-Seoane, Pau, Spurzem, Rainer
Compact object clusters are likely to exist in the centre of some galaxies because of mass segregation. The high densities and velocities reached in them deserves a better understanding. The...
Efficient Merger of Binary Supermassive Black Holes in Non-Axisymmetric Galaxies (2006)
Berczik, Peter, Merritt, David, Spurzem, Rainer, Bischof, Hans-Peter
Binary supermassive black holes form naturally in galaxy mergers, but their long-term evolution is uncertain. In spherical galaxies, N-body simulations show that binary evolution stalls at...
Performance Analysis of Direct N-Body Algorithms on Special-Purpose Supercomputers (2006)
Harfst, Stefan, Gualandris, Alessia, Merritt, David, Spurzem, Rainer, Zwart, Simon, Berczk, Peter
Direct-summation N-body algorithms compute the gravitational interaction between stars in an exact way and have a computational complexity of O(N^2). Performance can be greatly enhanced via the use...
Performance analysis of direct N-body algorithms on special-purpose supercomputers (2006)
Harfst, Stefan, Gualandris, Alessia, Merritt, David, Spurzem, Rainer, Zwart, Simon, Berczik, Peter
Direct-summation N-body algorithms compute the gravitational interaction between stars in an exact way and have a computational complexity of O(N^2). Performance can be greatly enhanced via the use...
Dynamics of compact object clusters: a post-Newtonian study (2006)
Kupi, Gabor, Amaro-Seoane, Pau, Spurzem, Rainer
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...
Dynamics of compact objects clusters: A post-Newtonian study (2006)
Kupi, Gabor, Amaro-Seoane, Pau, Spurzem, Rainer
Compact object clusters are likely to exist in the centre of some galaxies because of mass segregation. The high densities and velocities reached in them deserves a better understanding. The...
Merritt, David, Berczik, Peter, Spurzem, Rainer
Also archived in: arXiv:astro-ph/0507260 v1 11 Jul 2005
Berczik, Peter, Merritt, David, Spurzem, Rainer
Also archived in: arXiv:astro-ph/0507260 v1 11 Jul 2005
Berczik, Peter, Merritt, David, Spurzem, Rainer
We use direct-summation N-body integrations to follow the evolution of binary black holes at the centers of galaxy models with large, constant-density cores. Particle numbers as large as 400K are...
The Decay of Accreting Triple Systems as Brown Dwarf Formation Scenario (2005)
Umbreit, Stefan, Burkert, Andreas, Henning, Thomas, Mikkola, Seppo, Spurzem, Rainer
We investigate the dynamical decay of non-hierarchical accreting triple systems and its implications on the ejection model as Brown Dwarf formation scenario. A modified chain-regularization scheme is...
The decay of accreting triple systems as brown dwarf formation scenario (2005)
Umbreit, Stefan, Burkert, Andreas, Henning, Thomas, Mikkola, Seppo, Spurzem, Rainer
We investigate the dynamical decay of nonhierarchical accreting triple systems and its implications on the ejection model as a brown dwarf formation scenario. A modified chain-regularization scheme...
NBODY meets stellar population synthesis (2005)
Borch, Andrea, Spurzem, Rainer, Hurley, Jarrod
N-body simulations can give us a rough idea how does the shape of a simulated object in 3D space look like. From the obvervational point of view this may give us a misleading picture: A stellar...
NBODY meets stellar population synthesis (2005)
Borch, Andrea, Spurzem, Rainer, Hurley, Jarrod
N-body simulations can give us a rough idea how does the shape of a simulated object in 3D space look like. From the obvervational point of view this may give us a misleading picture: A stellar...
N-body growth of a bahcall-wolf cusp around a black hole (2004)
Merritt, David, Preto, Miguel, Spurzem, Rainer
Also archived in: arXiv:astro-ph/0406324 v2 9 Jul 2004
N-body growth of a bahcall-wolf cusp around a black hole (2004)
Merritt, David, Preto, Miguel, Spurzem, Rainer
Also archived in: arXiv:astro-ph/0406324 v2 9 Jul 2004
N-Body Growth of a Bahcall-Wolf Cusp Around a Black Hole (2004)
Preto, Miguel, Merritt, David, Spurzem, Rainer
We present a clear N-body realization of the growth of a Bahcall-Wolf f ~ E^0.25 (rho ~ 1/r^1.75) density cusp around a massive object ("black hole") at the center of a stellar system. Our N-body...
Dynamical Evolution of Rotating Stellar Systems: III. The Effect of Mass Spectrum (2004)
Kim, Eunhyeuk, Lee, Hyung Mok, Spurzem, Rainer
We have studied the dynamical evolution of rotating star clusters with mass spectrum using a Fokker-Planck code. As a simplest multi-mass model, we first investigated the two-component clusters....
Amaro-Seoane, Pau, Freitag, Marc, Spurzem, Rainer
To be presented is a study of the secular evolution of a spherical stellar system with a central star-accreting black hole (BH) using the anisotropic gaseous model. This method solves numerically...
Super-massive stars: Radiative transfer (2003)
Amaro-Seoane, Pau, Spurzem, Rainer, Just, Andreas
The concept of central super-massive stars (${\cal M} \ge 5 \times 10^4 M_{\odot}$, where ${\cal M}$ is the mass of the super-massive star) embedded in dense stellar systems was suggested as a...
Star close to the massive black hole at center of the Milky Way (2003)
Mouawad, Nelly, Eckart, Andreas, Pfalzner, Susanne, Straubmeier, Christian, Spurzem, Rainer, Genzel, Reinhard, ...
Dense gas-star systems: Super-massive stars evolution (2002)
Amaro-Seoane, Pau, Spurzem, Rainer
In the 60s and 70s super-massive central objects (from now onwards SMOs) were thought to be the main source of active galactic nuclei (AGNs) characteristics (luminosities of $L \approx 10^{12}...
Super-massive stars: Dense star-gas systems (2001)
Amaro-Seoane, Pau, Spurzem, Rainer, Just, Andreas
We use a gaseous model and a semi-analytical approach to study the evolution of a super-massive central gaseous object (a super-massive star, (SMS from now on) in an AGN and its evolution by...
Dynamical evolution of rotating stellar systems - II. Post-collapse, equal mass system (2001)
Kim, Eunhyeuk, Einsel, Christian, Lee, Hyung Mok, Spurzem, Rainer, Lee, Myung Gyoon
We present the first post core collapse models of initially rotating star clusters, using the numerical solution of an orbit-averaged 2D Fokker-Planck equation. Based on the code developed by Einsel...
The loss-cone problem in dense nuclei (2001)
Amaro-Seoane, Pau, Spurzem, Rainer
We address the classical problem of star accretion onto a supermassive central gaseous object in a galactic nucleus. The resulting supermassive central gas-star object is assumed to be located at the...
Collisional dynamics around binary black holes in galactic centers (2001)
Hemsendorf, Marc, Sigurdsson, Steinn, Spurzem, Rainer
We follow the sinking of two massive black holes in a spherical stellar system where the black holes become bound under the influence of dynamical friction. Once bound, the binary hardens by...
Three poster contributions to the Rutgers Dynamics Conference (1998)
Boily, Christian, Einsel, Christian, Hemsendorf, Marc, Spurzem, Rainer
1- Simulations of star clusters and galactic nuclei: rotation and other challenges (R. Spurzem & C. Einsel) 2- Relaxation of elliptical galaxies (C. Boily) 3- Simulations with an Hybrid Nbody-Scf...
Astrophysical N-body simulations: algorithms and challenges (1997)
The subjects and key questions faced by computational astrophysics using N-body simulations are discussed in the fields of globular star cluster dynamics, galactic nuclei and cosmological structure...
Direct collisional simulation of 10 000 particles past core collapse (1996)
Spurzem, Rainer, Aarseth, Sverre J.
A collisional $N$-body simulation using NBODY5 on a single CRAY YMP processor is followed well into the post-collapse regime. This is presently one of the largest particle numbers of all such models...
Comparative study of physical and numerical models of star clusters / (1996)
Kiel, University, Habil.-Schr., 1997 (Nicht für den Austausch).
Comparing Direct N-Body Integration with Anisotropic Gaseous Models of Star Clusters (1993)
Giersz, Mirek, Spurzem, Rainer
We compare the results for the dynamical evolution of star clusters derived from anisotropic gaseous models with the data from N-body simulations of isolated and one-component systems, each having...