A multiphysics and multiscale software environment for modeling astrophysical systems (2008)
Zwart, Simon Portegies, McMillan, Steve, Harfst, Stefan, Groen, Derek, Fujii, Michiko
We present MUSE, a software framework for combining existing computational tools for different astrophysical domains into a single multiphysics, multiscale application. MUSE facilitates the coupling...
A parallel gravitational N-body kernel (2007)
Zwart, Simon Portegies, McMillan, Steve, Groen, Derek, Gualandris, Alessia, Sipior, Michael, Vermin, Willem
We describe source code level parallelization for the {\tt kira} direct gravitational $N$-body integrator, the workhorse of the {\tt starlab} production environment for simulating dense stellar...
Distributed N-body Simulation on the Grid Using Dedicated Hardware (2007)
Groen, Derek, Zwart, Simon Portegies, McMillan, Steve, Makino, Jun
We present performance measurements of direct gravitational N -body simulation on the grid, with and without specialized (GRAPE-6) hardware. Our inter-continental virtual organization consists of...
The formation of higher-order hierarchical systems in star clusters (2006)
Berk, Jelle Van Den, Zwart, Simon Portegies, McMillan, Steve
We simulate open clusters containing up to 182 stars initially in the form of singles, binaries and triples. Due to the high interaction rate a large number of stable quadruples, quintuples,...
Zwart, Simon Portegies, McMillan, Steve, Makino, Jun
We study the first 100Myr of the evolution of isolated star clusters initially containing 144179 stars, including 13107 (10%) primordial hard binaries. Our calculations include the effects of both...
Planets in triple star systems--the case of HD188753 (2005)
Zwart, Simon Portegies, McMillan, Steve
We consider the formation of the recently discovered ``hot Jupiter'' planet orbiting the primary component of the triple star system HD188753. Although the current outer orbit of the triple is too...
Simulating young star clusters with primordial binaries (2004)
Zwart, Simon Portegies, McMillan, Steve
We simulate a cluster of 144179 stars including 13107 primordial hard binaries (10% of the total number of single stars and binary centers of mass), using direct integration of the equations of...
Black Holes in Massive Star Clusters (2004)
McMillan, Steve, Baumgardt, Holger, Zwart, Simon Portegies, Hut, Piet, Makino, Junichiro
Close encounters and physical collisions between stars in young dense clusters can result in new channels for stellar evolution, and may lead to the formation of very massive stars and black holes...
Dynamics of Intermediate Mass Black Holes in Star Clusters (2004)
Baumgardt, Holger, Zwart, Simon Portegies, McMillan, Steve, Makino, Jun, Ebisuzaki, Toshikazu
We have followed the evolution of multi-mass star clusters containing massive central black holes by N-body simulations on the GRAPE6 computers of Tokyo University. We find a strong cluster expansion...
The fate of star clusters near the Galactic center I: Analytic considerations (2003)
McMillan, Steve, Zwart, Simon Portegies
A star cluster in a galactic nucleus sinks toward the galactic center due to dynamical friction. As it spirals inward, the cluster loses mass due to stellar evolution, relaxation driven evaporation,...
Zwart, Simon Portegies, McMillan, Steve, Gerhard, Ortwin
We use direct N-body simulations to study the inspiral and internal evolution of dense star clusters near the Galactic center. These clusters sink toward the center due to dynamical friction with the...
A Dynamical Model for the Globular Cluster G1 (2003)
Baumgardt, Holger, Makino, Junichiro, Hut, Piet, McMillan, Steve, Zwart, Simon Portegies
We present a comparison between the observational data on the kinematical structure of G1 in M31, obtained with the Hubble WFPC2 and STIS instruments, and the results of dynamical simulations carried...
Star cluster ecology V: Dissection of an open star cluster--spectroscopy (2003)
Zwart, Simon Portegies, Hut, Piet, McMillan, Steve, Makino, Jun
We have modeled in detail the evolution of rich open star clusters such as the Pleiades, Praesepe and Hyades, using simulations that include stellar dynamics as well as the effects of stellar...
Sills, Alison, Deiters, Stefan, Eggleton, Peter P., Freitag, Marc, Giersz, Mirek, Heggie, Douglas C., ...
This is a summary paper of MODEST-2, a workshop held at the Astronomical Institute ‘Anton Pannekoek’ in Amsterdam, 16-17 December 2002. MODEST is a loose collaboration of people...
Sills, Alison, Deiters, Stefan, Eggleton, Peter P., Freitag, Marc, Giersz, Mirek, Heggie, Douglas C., ...
This is a summary paper of MODEST-2, a workshop held at the Astronomical Institute ‘Anton Pannekoek’ in Amsterdam, 16-17 December 2002. MODEST is a loose collaboration of people...
Sills, Alison, Deiters, Stefan, Eggleton, Peter P., Freitag, Marc, Giersz, Mirek, Heggie, Douglas C., ...
This is a summary paper of MODEST-2, a workshop held at the Astronomical Institute ‘Anton Pannekoek’ in Amsterdam, 16-17 December 2002. MODEST is a loose collaboration of people...
MODEST-1: Integrating Stellar Evolution and Stellar Dynamics (2002)
Hut, Piet, Shara, Michael M., Aarseth, Sverre J., Klessen, Ralf S., Lombardi Jr., James C., Makino, Junichiro, ...
We summarize the main results from MODEST-1, the first workshop on MOdeling DEnse STellar systems. Our goal is to go beyond traditional population synthesis models, by introducing dynamical...
Theory in a Virtual Observatory (2001)
Teuben, Peter, DeYoung, Dave, Hut, Piet, Levy, Stuart, Makino, Jun, McMillan, Steve, ...
During the last couple of years, observers have started to make plans for a Virtual Observatory, as a federation of existing data bases, connected through levels of software that enable rapid...
Missing Link Found? --- The ``runaway'' path to supermassive black holes (2001)
Ebisuzaki, Toshikazu, Makino, Junichiro, Tsuru, Takeshi Go, Funato, Yoko, Zwart, Simon Portegies, Hut, Piet, ...
Observations of stellar kinematics, gas dynamics and masers around galactic nuclei have now firmly established that many galaxies host central supermassive black holes (SMBHs) with masses in the...
Panel Discussion on Observing Simulations and Simulating Observations (2001)
Hut, Piet, Cool, Adrienne, Bailyn, Charles, McMillan, Steve, Livio, Mario, Shara, Mike
N-body simulations of star cluster evolution have reached a high degree of realism, by incorporating more and more elements of stellar dynamics, stellar evolution, and hydrodynamics. At the end of...
Immersive 4D Interactive Visualization of Large-Scale Simulations (2001)
Teuben, Peter, Hut, Piet, Levy, Stuart, Makino, Jun, McMillan, Steve, Zwart, Simon Portegies, ...
In dense clusters a bewildering variety of interactions between stars can be observed, ranging from simple encounters to collisions and other mass-transfer encounters. With faster and special-purpose...
Time-Symmetrized Kustaanheimo-Stiefel Regularization (1998)
. In this paper, we show a new algorithm to integrate the orbits of binaries. Our new algorithm has the good properties of both symmetrized timesteps and KS regularization: (1) no secular error in...
Smooth Particle Hydrodynamics: Models, Applications, and Enabling Technologies (1997)
Hut, Piet, Hernquist, Lars, Lake, George, Makino, Jun, McMillan, Steve, Sterling, Thomas
We present the results from a two-day study in which we discussed various implementations of Smooth Particle Hydrodynamics (SPH), one of the leading methods used across a variety of areas of...
Time Symmetrization Meta-Algorithms (1997)
Hut, Piet, Funato, Yoko, Kokubo, Eiichiro, Makino, Junichiro, McMillan, Steve
We present two types of meta-algorithm that can greatly improve the accuracy of existing algorithms for integrating the equations of motion of dynamical systems. The first meta-algorithm takes an...
Time-Symmetrized Kustaanheimo-Stiefel Regularization (1996)
Yoko Funato, Steve Mcmillan, Junichiro Makino
In this paper we describe a new algorithm for the long-term numerical integration of the two-body problem, in which two particles interact under a Newtonian gravitational potential. Although...
Time-Symmetrized Kustaanheimo-Stiefel Regularization (1996)
Yoko Funato, Steve Mcmillan, Junichiro Makino
In this paper we describe a new algorithm for the long-term numerical integration of the two-body problem, in which two particles interact under a Newtonian gravitational potential. Although...
The Ethical Dilemma of Research and Development Openness Versus Secrecy
Steve McMillan, Ronald Duska, Robert Hamilton, Debra Casey
In previous research, we have argued that private companies should be more open with their scientific research findings. However, our research assumed, somewhat naively perhaps, that public...