100 citations · 528 across the 57 of their papers we have counts for
57 papers
BlackHoleWeather -- Spin-coupled chaotic cold accretion across the meso scale: Variability and kinematics
Olmo Piana, Massimo Gaspari, Vieri Cammelli +10
Supermassive black hole (SMBH) spin records the vector history of accretion. In chaotic cold accretion (CCA), this history is set by clouds and filaments whose torques can add cohe…
BlackHoleWeather -- Chaotic cold accretion across the meso-scale: Morphology and thermodynamics
Filippo Barbani, Massimo Gaspari, Vieri Cammelli +12
Supermassive black holes (SMBHs) self-regulate galaxies, groups, and clusters, yet the pathway transporting gas from halo scales to sub-pc radii remains debated. In hot stratified…
BlackHoleWeather -- Chaotic cold accretion across the meso-scale: Variability and kinematics
Filippo Barbani, Massimo Gaspari, Olmo Piana +12
Accretion onto supermassive black holes (SMBHs) in realistic halos is time-variable, governed by turbulence, cooling, and multiphase condensation. In chaotic cold accretion (CCA),…
BlackHoleWeather -- Jet-regulated chaotic cold accretion across the meso scale: Morphology and thermodynamics
Vieri Cammelli, Massimo Gaspari, Olmo Piana +11
How mechanical AGN feedback couples to multiphase condensation across scales remains a problem in galaxy groups and clusters. It is unclear how jets reshape the chaotic cold accret…
BlackHoleWeather -- Spin-coupled chaotic cold accretion across the meso-scale: Morphology and thermodynamics
Olmo Piana, Massimo Gaspari, Filippo Barbani +10
Supermassive black hole (SMBH) spin is a key but poorly constrained ingredient of the feeding-feedback loop. Chaotic cold accretion (CCA) of cold gas clouds delivers rapidly varyin…
IGR J12580+0134: The Nearest Tidal Disruption Event and its Faint Resurrection
A. Danehkar
Tidal disruption events (TDEs) are X-ray and gamma-ray radiations emerging from the tidal disintegration of a star or substellar object that passes too close to a supermassive blac…
Accretion-disk reflection in the Seyfert 1 galaxy NGC 3783 as viewed by Chandra grating spectroscopy
A. Danehkar, W. N. Brandt
In active galactic nuclei, X-ray illumination of the accretion disk around a supermassive black hole (SMBH) results in the production of the K fluorescent line of iron, which pr…
Relativistic Reflection Modeling in AGN and Related Variability from PCA: A Brief Review
A. Danehkar
X-ray observations of active galactic nuclei (AGNs) reveal relativistic reflections from the innermost regions of accretion disks, which contain general-relativistic footprints cau…
pyEQUIB Python Package, an addendum to proEQUIB: IDL Library for Plasma Diagnostics and Abundance Analysis
A. Danehkar
The emission lines from ionized nebulae allow us to determine their physical and chemical properties, along with the interstellar extinction. "pyEQUIB" is a pure Python open-source…
Disentangling the X-ray variability in the Lyman continuum emitter Haro 11
A. Danehkar, S. Silich, E. C. Herenz +1
Lyman break analogs in the local Universe serve as counterparts to Lyman break galaxies (LBGs) at high redshifts, which are widely regarded as major contributors to cosmic reioniza…
Numerical Modeling of Galactic Superwinds with Time-evolving Stellar Feedback
A. Danehkar, M. S. Oey, W. J. Gray
Mass-loss and radiation feedback from evolving massive stars produce galactic-scale superwinds, sometimes surrounded by pressure-driven bubbles. Using the time-dependent stellar po…
X-ray Variability in the Symbiotic Binary RT Cru: Principal Component Analysis
A. Danehkar, J. J. Drake, G. J. M. Luna
Hard X-ray-emitting (-type) symbiotic binaries, which exhibit a strong hard X-ray excess, have posed a challenge to our understanding of accretion physics in degenerate dwarfs.…
Nebular C IV 1550 Imaging of the Metal-Poor Starburst Mrk 71: Direct Evidence of Catastrophic Cooling
M. S. Oey, Amit N. Sawant, Ashkbiz Danehkar +10
We use the Hubble Space Telescope ACS camera to obtain the first spatially resolved, nebular imaging in the light of C IV 1548,1551 by using the F150LP and F165LP filters. These ob…
Silicon K-edge Dust Properties of Neutron Star Low-mass X-ray Binaries
A. Danehkar
The dust properties of the line-of-sight materials in neutron star low-mass X-ray binaries (LMXBs) can be probed by X-ray observations and laboratory experiments. We use a Markov c…
Hydrodynamic Simulations and Time-dependent Photoionization Modeling of Starburst-driven Superwinds
A. Danehkar, M. S. Oey, W. J. Gray
Thermal energies deposited by OB stellar clusters in starburst galaxies lead to the formation of galactic superwinds. Multi-wavelength observations of starburst-driven superwinds p…
Catastrophic Cooling in Superwinds. III. Non-equilibrium Photoionization
A. Danehkar, M. S. Oey, W. J. Gray
Observations of some starburst-driven galactic superwinds suggest that strong radiative cooling could play a key role in the nature of feedback and the formation of stars and molec…
Covariant Evolution of Gravitoelectromagnetism
A. Danehkar
The long-range gravitational terms associated with tidal forces, frame-dragging effects, and gravitational waves are described by the Weyl conformal tensor, the traceless part of t…
Physical Conditions and Chemical Abundances of the Variable Planetary Nebula IC 4997
A. Danehkar, M. Parthasarathy
The planetary nebula (PN) IC 4997 is one of a few rapidly evolving objects with variable brightness and nebular emission around a hydrogen-deficient star. In this study, we have de…
Morphologies of Wolf-Rayet Planetary Nebulae based on IFU Observations
A. Danehkar
Integral field unit (IFU) spectroscopy of planetary nebulae (PNe) provides a plethora of information about their morphologies and ionization structures. An IFU survey of a sample o…
3D spatio-kinematic modeling of Abell 48, a planetary nebula around a Wolf-Rayet [WN] star
A. Danehkar
The planetary nebula (PN) Abell 48 (PN G029.0+00.4) is around a rare Wolf-Rayet [WN5] star whose stellar history is as yet unknown. Using the integral field observations of the H$α…
Non-equilibrium Photoionization and Hydrodynamic Simulations of Starburst-driven Outflows
A. Danehkar, M. S. Oey, W. J. Gray
Starburst-driven galactic outflows in star-forming galaxies have been observed to contain complex thermal structures and emission line features that are difficult to explain by adi…
Dual Fields of Massive/Massless Gravitons in IR/UV Completions
Ashkbiz Danehkar, Hassan Alshal, Thomas L. Curtright
In the holographic picture, the Brout-Englert-Higgs (BEH) mechanism in d-dimensional Yang-Mills theories is conjectured to provide a Higgs-like mechanism for gravity in d+1 dimensi…
Morpho-kinematic properties of Wolf-Rayet planetary nebulae
A. Danehkar
The majority of planetary nebulae (PNe) show axisymmetric morphologies, whose causes are not well understood. In this work, we present spatially resolved kinematic observations of…
Catastrophic Cooling in Superwinds. II. Exploring the Parameter Space
Ashkbiz Danehkar, M. S. Oey, William J. Gray
Superwinds and superbubbles driven by mechanical feedback from super star clusters (SSCs) are common features in many star-forming galaxies. While the adiabatic fluid model can wel…