Publications (44)
Dual black holes in merger remnants. II: spin evolution and gravitational recoil
M. Dotti, M. Volonteri, A. Perego +3
Using high resolution hydrodynamical simulations, we explore the spin evolution of massive dual black holes orbiting inside a circumnuclear disc, relic of a gas-rich galaxy merger.…
Shock heating by FR I radio sources in galaxy clusters
M. Brueggen, S. Heinz, E. Roediger +2
Feedback by active galactic nuclei (AGN) is frequently invoked to explain the cut-off of the galaxy luminosity function at the bright end and the absence of cooling flows in galaxy…
A Global Stability Analysis of Clusters of Galaxies with Conduction and AGN Feedback Heating
Fulai Guo, S. Peng Oh, M. Ruszkowski
We investigate a series of steady-state models of galaxy clusters, in which the hot intracluster gas is efficiently heated by active galactic nucleus (AGN) feedback and thermal con…
The Fermi Bubbles: Gamma-ray, Microwave, and Polarization Signatures of Leptonic AGN Jets
H. -Y. K. Yang, M. Ruszkowski, E. Zweibel
The origin of the Fermi bubbles and the microwave haze is yet to be determined. To disentangle different models requires detailed comparisons between theoretical predictions and mu…
X-ray line tomography of AGN-induced motion in clusters of galaxies
M. Brueggen, M. Hoeft, M. Ruszkowski
The thermal broadening of emission lines of heavy ions is small enough such that Doppler shifts due to bulk motions may be detected with the next generation of X-ray observatories.…
Fermi bubble simulations: black hole feedback in the Milky Way
M. Ruszkowski, H. -Y. K. Yang, E. Zweibel
The gamma-ray telescope discovered a pair of bubbles at the Galactic center. These structures are spatially-correlated with the microwave emission detected by the WMAP and…
Entropy "floor" and effervescent heating of intracluster gas
S. Roychowdhury, M. Ruszkowski, B. B. Nath +1
Recent X-ray observations of clusters of galaxies have shown that the entropy of the intracluster medium (ICM), even at radii as large as half the virial radius, is higher than tha…
Relighting the fire in Hickson Compact Group (HCG) 15: magnetised fossil plasma revealed by the SKA Pathfinders & Precursors
C. J. Riseley, T. Vernstrom, L. Lovisari +26
In the context of the life cycle and evolution of active galactic nuclei (AGN), the environment plays an important role. In particular, the over-dense environments of galaxy groups…
The Spatially Uniform Spectrum of the Fermi Bubbles: the Leptonic AGN Jet Scenario
H. -Y. K. Yang, M. Ruszkowski
The Fermi bubbles, two giant gamma-ray bubbles above and below the Galactic center (GC), are among the most important findings of the Fermi Gamma-ray Space Telescope. Because of th…
Solving the Cooling Flow Problem through Mechanical AGN Feedback
M. Gaspari, F. Brighenti, M. Ruszkowski
Unopposed radiative cooling of plasma would lead to the cooling catastrophe, a massive inflow of condensing gas, manifest in the core of galaxies, groups and clusters. The last gen…
Cosmic ray feedback heating of the intracluster medium
M. Ruszkowski, H. -Y. K. Yang, C. S. Reynolds
Self-regulating AGN feedback in the cool cores of galaxy clusters plays central role in solving the decades-old cooling flow problem, but one major problem remains unsolved - how i…
Impact of Cosmic Ray Transport on Galactic Winds
R. Farber, M. Ruszkowski, H. -Y. K. Yang +1
The role of cosmic rays generated by supernovae and young stars has very recently begun to receive significant attention in studies of galaxy formation and evolution due to the rea…
Galaxy Motions, Turbulence and Conduction in Clusters of Galaxies
M. Ruszkowski, S. Peng Oh
Unopposed radiative cooling in clusters of galaxies results in excessive mass deposition rates. However, the cool cores of galaxy clusters are continuously heated by thermal conduc…
AGN pairs: chance superpositions or black hole binaries?
M. Dotti, M. Ruszkowski
Several active galactic nuclei (AGN) with multiple sets of emission lines separated by over 2000 km/s have been observed recently. These have been interpreted as being due to massi…
Unveiling the Origin of the Fermi Bubbles
H. -Y. K. Yang, M. Ruszkowski, E. G. Zweibel
The Fermi bubbles, two giant structures above and below the Galactic center (GC), are among the most important discoveries of the Fermi Gamma-ray Space Telescope. Studying their ph…
Powering of cool filaments in cluster cores by buoyant bubbles. I. Qualitative model
E. Churazov, M. Ruszkowski, A. Schekochihin
Cool-core clusters (e.g., Perseus or M87) often possess a network of bright gaseous filaments, observed in radio, infrared, optical and X-ray bands. We propose that these filaments…
The origin of cold gas in giant elliptical galaxies and its role in fueling radio-mode AGN feedback
N. Werner, J. B. R. Oonk, M. Sun +12
We present a multi-wavelength study of the interstellar medium in eight nearby, X-ray and optically bright, giant elliptical galaxies. Using Herschel PACS, we map the cold gas in t…
The Evolution of Galaxy Clusters Across Cosmic Time
M. Arnaud, H. Bohringer, C. Jones +40
The large scale structure of the present Universe is determined by the growth of dark matter density fluctuations and by the dynamical action of dark energy and dark matter. While…
Are black holes big enough to quench cooling in cluster cool cores?
M. Ruszkowski
Total energy arguments (e.g., Fabian et al. 2002) suggest that black holes need to have masses significantly in excess of the prediction from the classic black hole mass - velocity…
Deep Chandra observation and numerical studies of the nearest cluster cold front in the sky
N. Werner, J. A. ZuHone, I. Zhuravleva +9
We present the results of a very deep (500 ks) Chandra observation, along with tailored numerical simulations, of the nearest, best resolved cluster cold front in the sky, which li…
Impact of tangled magnetic fields on AGN-blown bubbles
M. Ruszkowski, T. A. Ensslin, M. Bruggen +2
There is growing consensus that feedback from AGN is the main mechanism responsible for stopping cooling flows in clusters of galaxies. AGN are known to inflate buoyant bubbles tha…
Shock-Driven Periodic Variability in a Low-Mass-Ratio Supermassive Black Hole Binary
K. Whitley, A. Kuznetsova, K. Gültekin +1
We investigate the time-varying electromagnetic emission of a low-mass-ratio supermassive black hole binary (SMBHB) embedded in a circumprimary disk, with a particular interest in…
Fermi and eRosita bubbles as relics of the past activity of the Galactic black hole
H. -Y. Karen Yang, M. Ruszkowski, E. Zweibel
The newly launched X-ray satellite, eRosita, has recently revealed two gigantic bubbles extending to ~80 degrees above and below the Galactic center. The morphology of these "eRosi…
Non-Kolmogorov turbulence in multiphase intracluster medium driven by cold gas precipitation and AGN jets
C. Wang, M. Ruszkowski, C. Pfrommer +2
AGN feedback is responsible for maintaining plasma in global thermal balance in extended halos of elliptical galaxies and galaxy clusters. Local thermal instability in the hot gas…
Dual black holes in merger remnants. I: linking accretion to dynamics
M. Dotti, M. Ruszkowski, L. Paredi +3
We study the orbital evolution and accretion history of massive black hole (MBH) pairs in rotationally supported circumnuclear discs up to the point where MBHs form binary systems.…
In-depth Chandra study of the AGN feedback in Virgo elliptical galaxy M84
A. Finoguenov, M. Ruszkowski, C. Jones +3
Using deep Chandra observations of M84 we study the energetics of the interaction between the black hole and the interstellar medium of this early-type galaxy. We perform a detaile…
Impact of magnetic fields on ram pressure stripping in disk galaxies
M. Ruszkowski, M. Bruggen, D. Lee +1
(abridged) Ram pressure can remove significant amounts of gas from galaxies in clusters, and thus has a large impact on the evolution of cluster galaxies. Recent observations have…
Cosmological MHD simulations of cluster formation with anisotropic thermal conduction
M. Ruszkowski, D. Lee, M. Bruggen +2
(abridged) The ICM has been suggested to be buoyantly unstable in the presence of magnetic field and anisotropic thermal conduction. We perform first cosmological simulations of ga…
The Fermi Bubbles: Supersonic AGN Jets with Anisotropic Cosmic Ray Diffusion
H. -Y. K. Yang, M. Ruszkowski, P. M. Ricker +2
The Fermi Gamma-ray Space Telescope reveals two large bubbles in the Galaxy, which extend nearly symmetrically ~50 degrees above and below the Galactic center (GC). Using three-dim…
Shaken and stirred: conduction and turbulence in clusters of galaxies
M. Ruszkowski, S. Peng Oh
(abridged) Uninhibited radiative cooling in clusters of galaxies would lead to excessive mass accretion rates contrary to observations. One of the key proposals to offset radiative…
Cosmic ray confinement in fossil cluster bubbles
M. Ruszkowski, T. A. Ensslin, M. Bruggen +2
Most cool core clusters of galaxies possess active galactic nuclei (AGN) in their centers. These AGN inflate buoyant bubbles containing non-thermal radio emitting particles. If suc…
Viscosity in cosmological simulations of clusters of galaxies
M. Brüggen, M. Ruszkowski
The physics of the intracluster medium, in particular the values for the thermal conductivity and the viscosity are largely unknown and subject to an ongoing debate. Here, we study…
Cause and Effect of Feedback: Multiphase Gas in Cluster Cores Heated by AGN Jets
M. Gaspari, M. Ruszkowski, P. Sharma
Multiwavelength data indicate that the X-ray emitting plasma in the cores of galaxy clusters is not cooling catastrophically. To large extent, cooling is offset by heating due to a…
The nature of filamentary cold gas in the core of the Virgo Cluster
N. Werner, J. B. R. Oonk, R. E. A. Canning +10
We present a multi-wavelength study of the emission-line nebulae located southeast of the nucleus of M87, the central dominant galaxy of the Virgo Cluster. We report the detection…
AGN Feedback and Bimodality in Cluster Core Entropy
Fulai Guo, S. Peng Oh, M. Ruszkowski
We investigate a series of steady-state models of galaxy clusters, in which the hot intracluster gas is efficiently heated by active galactic nucleus (AGN) feedback and thermal con…
Role of Cosmic Ray Streaming and Turbulent Damping in Driving Galactic Winds
F. Holguin, M. Ruszkowski, A. Lazarian +2
Large-scale galactic winds driven by stellar feedback are one phenomenon that influences the dynamical and chemical evolution of a galaxy, redistributing material throughout the ci…
Turbulent Heating in a Stratified Medium
Chaoran Wang, S. Peng Oh, M. Ruszkowski
There is considerable evidence for widespread subsonic turbulence in galaxy clusters, most notably from {\it Hitomi}. Turbulence is often invoked to offset radiative losses in clus…
Simulations of magnetic fields in filaments
M. Bruggen, M. Ruszkowski, A. Simionescu +2
The intergalactic magnetic field within filaments should be less polluted by magnetised outflows from active galaxies than magnetic fields in clusters. Therefore, filaments may be…
Whistler-regulated MHD: Transport equations for electron thermal conduction in the high intracluster medium of galaxy clusters
J. F. Drake, C. Pfrommer, C. S. Reynolds +6
Transport equations for electron thermal energy in the high intracluster medium (ICM) are developed that include scattering from both classical collisions and self-generated…
AGN heating and dissipative processes in galaxy clusters
M. Bruggen, M. Ruszkowski, E. Hallman
Recent X-ray observations reveal growing evidence for heating by active galactic nuclei (AGN) in clusters and groups of galaxies. AGN outflows play a crucial role in explaining the…
Chaotic cold accretion onto black holes
M. Gaspari, M. Ruszkowski, S. Peng Oh
Using 3D AMR simulations, linking the 50 kpc to the sub-pc scales over the course of 40 Myr, we systematically relax the classic Bondi assumptions in a typical galaxy hosting a SMB…
ROSAT HRI Monitoring of Extreme X-ray Variability in the Narrow-Line Quasar PHL 1092
W. N. Brandt, Th. Boller, A. C. Fabian +1
We report results from an 18-day ROSAT HRI monitoring campaign on the ultrasoft Narrow-Line Seyfert 1 (NLS1) class quasar PHL 1092. This luminous, radio-quiet quasar showed strong…
AGN heating, thermal conduction and Sunyaev-Zeldovich effect in galaxy groups and clusters
S. Roychowdhury, M. Ruszkowski, B. B. Nath
(abridged) We investigate in detail the role of active galactic nuclei on the physical state of the gas in galaxy groups and clusters, and the implications for anisotropy in the CM…
Cold Fronts and Gas Sloshing in Galaxy Clusters with Anisotropic Thermal Conduction
J. A. ZuHone, M. Markevitch, M. Ruszkowski +1
(Abridged) Cold fronts in cluster cool cores should be erased on short timescales by thermal conduction, unless protected by magnetic fields that are "draped" parallel to the front…