Publications (43)
Dynamical evolution of the open clusters with different star formation efficiencies and orbital parameters
M. Ishchenko, V. Masliukh, M. Hradov +3
Open star clusters are dynamic systems whose evolution is critically influenced by initial conditions such as star formation efficiency and orbital parameters. Understanding their…
Peculiar motions of the gas at the centre of the barred galaxy UGC 4056
I. A. Zinchenko, L. S. Pilyugin, F. Sakhibov +6
We derive the circular velocity curves of the gaseous and stellar discs of UGC 4056, a giant barred galaxy with an active galactic nucleus (AGN). We analyse UGC 4056 using the 2D s…
Mitigating potentially hazardous asteroid impacts revisited
Zs. Regaly, V. Frohlich, P. Berczik
Context: Potentially hazardous asteroids (PHA) in Earth-crossing orbits pose a constant threat to life on Earth. Several mitigation methods have been proposed, and the most feasibl…
Roche volume filling and the dissolution of open star clusters
A. Ernst, P. Berczik, A. Just +1
From direct N-body simulations we find that the dynamical evolution of star clusters is strongly influenced by the Roche volume filling factor. We present a parameter study of the…
Is the overconcentration of pristine populations in Galactic globular clusters real? An N-body approach to the problem
P. Berczik, O. Sobodar, F. Flammini Dotti +5
Recent observations indicate that in some Milky Way globular clusters (GCs) pristine red giant branch (RGB) stars appear more centrally concentrated than enriched ones. This contra…
The contribution to Galactic Centre γ-ray excess from cluster-born millisecond pulsars. Constraints from direct N-body simulations
M. Kalambay, M. Ishchenko, D. Kuvatova +2
The Galactic Centre γ-ray excess (GCE), observed by Fermi-LAT around Sgr A*, exceeds expectations from standard cosmic-ray models and is commonly attributed either to dark matter…
Global survey of star clusters in the Milky Way VI. Age distribution and cluster formation history
A. E. Piskunov, A. Just, N. V. Kharchenko +4
The all-sky Milky Way Star Clusters (MWSC) survey provides uniform and precise ages and other parameters for a variety of clusters in the Solar Neighbourhood. We construct the clus…
High resolution in z-direction: The simulation of disc-bulge-halo galaxies using the particle-mesh code SUPERBOX
R. Bien, A. Just, P. Berczik +1
SUPERBOX is known as a very efficient particle-mesh code with highly-resolving sub-grids. Nevertheless, the height of a typical galactic disc is small compared to the size of the w…
Bar formation in the Milky Way type galaxies
E. V. Polyachenko, P. Berczik, A. Just
Many barred galaxies, possibly including the Milky Way, have cusps in the centres. There is a widespread belief, however, that usual bar instability taking place in bulgeless galax…
On the isolated dwarf galaxies: from cuspy to flat dark matter density profiles and metallicity gradients
S. Pasetto, E. K. Grebel, P. Berczik +2
The chemodynamical evolution of spherical multi-component self-gravitating models for isolated dwarf galaxies is studied. We compare their evolution with and without feedback effec…
Simulation of the loss-cone instability in spherical systems. I. Dominating harmonic potential
E. V. Polyachenko, P. Berczik, A. Just +1
A new so-called `gravitational loss-cone instability' in stellar systems has recently been investigated theoretically in the framework of linear perturbation theory and proved to b…
Physical Processes in Star-Gas Systems
R. Spurzem, P. Berczik, G. Hensler +4
First we present a recently developed 3D chemodynamical code for galaxy evolution from the K**2 collaboration. It follows the evolution of all components of a galaxy such as dark m…
Dynamical evolution timescales for the triple supermassive black hole system in NGC 6240
P. Berczik, M. Sobolenko, M. Ishchenko
Based on the available observational data from the literature, we analysed the dynamics of the NGC 6240 galaxy central supermassive black hole (SMBH) system. For the dynamical mode…
Simulation of the loss-cone instability in spherical systems. II. Dominating Keplerian potential
E. V. Polyachenko, P. Berczik, A. Just +1
A new so-called `gravitational loss-cone instability' in stellar systems has recently been investigated theoretically in the framework of linear perturbation theory and proved to b…
Chemodynamical Modelling of Galaxy Formation and Evolution
P. Berczik, G. Hensler, Ch. Theis +1
We present our recently developed 3-dimensional chemodynamical code for galaxy evolution. This code follows the evolution of different galactic components like stars, dark matter a…
Up to 700k GPU cores, Kepler, and the Exascale future for simulations of star clusters around black holes
P. Berczik, R. Spurzem, L. Wang +9
We present direct astrophysical N-body simulations with up to a few million bodies using our parallel MPI/CUDA code on large GPU clusters in China, Ukraine and Germany, with differ…
The study of colliding molecular clumps evolution
S. B. Vinogradov, P. Berczik
The results of study of the gravitational fragmentation in the interstellar medium (ISM) by clump-clump collisions are presented. We suggest, that collision of clumps, that are sub…
Simulations of the Hyades
A. Ernst, A. Just, P. Berczik +1
Context: Using the recent observational data of Röser et al. we present -body simulations of the Hyades open cluster. Aims: We make an attempt to determine initial conditions o…
Cluster membership analysis with supervised learning and -body simulations
A. Bissekenov, M. Kalambay, E. Abdikamalov +3
Membership analysis is an important tool for studying star clusters. There are various approaches to membership determination, including supervised and unsupervised machine learnin…
The impact of stellar evolution on rotating star clusters: the gravothermal-gravogyro catastrophe and the formation of a bar of black holes
A. W. H. Kamlah, R. Spurzem, P. Berczik +7
We present results from a suite of eight direct N-body simulations, performed with \textsc{Nbody6++GPU}, representing realistic models of rotating star clusters with up to $1.1\tim…
Quantitative analysis of clumps in the tidal tails of star clusters
A. Just, P. Berczik, M. I. Petrov +1
Tidal tails of star clusters are not homogeneous but show well defined clumps in observations as well as in numerical simulations. Recently an epicyclic theory for the formation of…
Effects of galaxy--satellite interactions on bar formation
R. Moetazedian, E. V. Polyachenko, P. Berczik +1
Aims. We aim to show how encounters with low-mass satellite galaxies may alter the bar formation in a Milky Way-like disc galaxy. Methods. We use high-resolution N-body simulations…
Calibration of radii and masses of open clusters with a simulation
A. Ernst, A. Just, P. Berczik +1
Context: A recent new approach to apply a simple dynamical mass estimate of tidally limited star clusters is based on the identification of the tidal radius in a King profile with…
Simulation of the Gravitational Collapse and Fragmentation of Rotating Molecular Clouds
P. Berczik, M. I. Petrov
In this paper we study the process of the subsequent (runaway) fragmentation of the rotating isothermal Giant Molecular Cloud (GMC) complex. Our own developed Smoothed Particle Hyd…
Dynamical evolution of Milky Way globular clusters on the cosmological timescale II. Terzan 2, 4, and 5 mass loss and collision tracking
M. Ishchenko, P. Berczik, D. Kuvatova
We investigate the long-term dynamical evolution of Ter2, Ter4, and Ter5, focusing on their mutual interactions, mass-loss behaviour, and survivability in the dense Galactic centre…
A Multi-Phase Chemo-Dynamical SPH Code for Galaxy Evolution
P. Berczik, G. Hensler, Ch. Theis +1
In this paper we present some test results of our newly developed Multi-Phase Chemo-Dynamical Smoothed Particle Hydrodynamics (MP- CD-SPH) code for galaxy evolution. At first, we p…
Gravitational influence of the globular cluster NGC 7078 (M 15) flyby of the Oort cloud system
M. Ishchenko, P. Berczik
Context. It is crucial to understand the interaction between globular clusters (GCs) and the Oort cloud, as close flybys of such massive objects can significantly disturb the cloud…
Dynamical friction of massive objects in galactic centres
A. Just, F. M. Khan, P. Berczik +2
Dynamical friction leads to an orbital decay of massive objects like young compact star clusters or Massive Black Holes in central regions of galaxies. The dynamical friction force…
Shape parameters of Galactic open clusters
N. V. Kharchenko, P. Berczik, M. I. Petrov +4
(abridged) In this paper we derive observed and modelled shape parameters (apparent ellipticity and orientation of the ellipse) of 650 Galactic open clusters identified in the ASCC…
Post-Newtonian simulations of super-massive black hole binaries in galactic nuclei
I. Berentzen, M. Preto, P. Berczik +2
We present some preliminary results from recent numerical simulations that model the evolution of super-massive black hole (SMBH) binaries in galactic nuclei. Including the post-Ne…
Chemodynamical Modeling of Dwarf Galaxy Evolution
P. Berczik, G. Hensler, Ch. Theis +1
We present our recently developed 3-dimensional chemodynamical code for galaxy evolution. It follows the evolution of all components of a galaxy such as dark matter, stars, molecul…
Dynamical evolution of Milky Way globular clusters on the cosmological timescale I. Mass loss and interaction with the nuclear star cluster
M. Ishchenko, P. Berczik, T. Panamarev +7
Context. Based on the Gaia DR3, we reconstructed the orbital evolution of the known Milky Way globular clusters and found that six objects, NGC 6681, NGC 6981, Palomar 6, NGC 6642,…
How our proto-nuclear star cluster formed and grew due to early globular cluster disruption. I. Case of low masses
D. Kuvatova, M. Ishchenko, P. Berczik +3
We investigate the accretion of globular cluster stars on early cosmological timescales through detailed N-body simulations of theoretical GC models to assess the role of this mech…
The star cluster survivability after gas expulsion is independent of the impact of the Galactic tidal field
B. Shukirgaliyev, G. Parmentier, P. Berczik +1
We study the impact of the tidal field on the survivability of star clusters following instantaneous gas expulsion. Our model clusters are formed with a centrally-peaked star-forma…
The bound mass of Dehnen models with centrally peaked star formation efficiency
B. Shukirgaliyev, A. Otebay, M. Sobolenko +12
Understanding the formation of star clusters with low star-formation efficiency (SFE) is very important to know about the star-formation history. In N-body models of star cluster e…
Cosmological insights into the early accretion of r-process-enhanced stars II. Dynamical identification of lost members of Reticulum II
P. Berczik, M. Ishchenko, O. Sobodar +1
Aims. We identify the possible dynamical connection between individual r-process-enhanced stars and the ultra-faint dwarf galaxy Reticulum II based on the current phase-space infor…
Dynamical model of Praesepe and its tidal tails
L. Weis, C. West, A. Just +5
Context. The dynamical evolution of open clusters in the tidal field of the Milky Way and the feeding of the disc field star population depend strongly on the initial conditions at…
NGC 6240 Supermassive Black Hole Binary dynamical evolution based on Chandra data
M. Sobolenko, O. Kompaniiets, P. Berczik +4
The main idea of our research is to estimate the physical coalescence time of the double supermassive black hole (SMBH) system in the centre of NGC 6240 based on the X-ray observat…
Evolution of open clusters with or without black holes
B. Shukirgaliyev, P. Berczik, A. Otebay +6
Binary black holes (BHs) can be formed dynamically in the centers of star clusters. The high natal kicks for stellar-mass BHs used in previous works made it hard to retain BHs in s…
Milky Way globular clusters on cosmological timescales. I. Evolution of the orbital parameters in time-varying potentials
M. Ishchenko, M. Sobolenko, P. Berczik +4
Context. Recent observational data show that the Milky Way (MW) galaxy contains about 170 globular clusters (GCs). A fraction of them is likely formed in dwarf galaxies accreted on…
Preparing the next gravitational million-body simulations: Evolution of single and binary stars in Nbody6++GPU, MOCCA and McLuster
A. W. H. Kamlah, A. Leveque, R. Spurzem +9
We present the implementation of updated stellar evolution recipes in the codes \texttt{Nbody6++GPU, MOCCA} and \texttt{McLuster}. We test them through numerical simulations of sta…
Dynamical evolution timescales for the supermassive black hole system in the galaxy NGC 7727 (Arp 222)
P. Berczik, M. Ishchenko, O. Veles +5
Context. A dual active galactic nucleus candidate with a separation of only 500 pc was recently found in NGC 7727. According to the hierarchical merging scenario, such objects woul…
Orbital evolution of the Carina dwarf galaxy and self-consistent star formation history determination
S. Pasetto, E. K. Grebel, P. Berczik +2
We present a new study of the evolution of the Carina dwarf galaxy that includes a simultaneous derivation of its orbit and star formation history. The structure of the galaxy is c…