Related papers: A Stellar Wind Origin for the G2 Cloud: Three-Dime…
The reported discovery of a cold (~10$^4$ K) disc-like structure within 0.005 pc around the super-massive black hole at the centre of the Milky Way, Sgr A*, has challenged our understanding of the gas dynamics and thermodynamic state of the…
Super-massive black holes (SMBH) are present at the center of most galaxies, with the related mass accretion processes giving origin to outflows in Active Galactic Nuclei (AGN). It has been presumed that only intense winds from luminous AGN…
The supermassive black hole at the Galactic center, Sagittarius A*, has experienced periods of higher activity in the past. The reflection of these past outbursts is observed in the molecular material surrounding the black hole but…
We present 3D general relativistic magnetohydrodynamic (GRMHD) simulations of the accretion flow surrounding Sagittarius A* that are initialized using larger-scale MHD simulations of the $\sim$ 30 Wolf--Rayet (WR) stellar winds in the…
We study the Galactic bulge planetary nebula M 2-29 (for which a 3-year eclipse event of the central star has been attributed to a dust disk) using HST imaging and VLT spectroscopy, both long-slit and integral field. The central cavity of M…
Wind is believed to be widespread in various black hole accretion flows. However, unlike the wind from thin disks, which have substantial observational evidence, the wind from hot accretion flows is difficult to observe due to the extremely…
We propose that the large, radius of ~1000 AU, circumbinary rotating disks observed around some post-asymptotic giant branch (post-AGB) binary stars are formed from slow AGB wind material that is pushed back to the center of the nebula by…
Winds arising from galaxies, star clusters, and active galactic nuclei are crucial players in star and galaxy formation, but it has proven remarkably difficult to use observations of them to determine physical properties of interest,…
Successful models of the low redshift circumgalactic medium (CGM) must account for (1) a large amount of gas, (2) relatively slow gas velocities, (3) a high degree of metal enrichment, (4) the similar absorption properties around both…
Low- and intermediate-mass stars eject much of their mass during the late, red giant branch (RGB) phase of evolution. The physics of their strong stellar winds is still poorly understood. In the standard model, stellar pulsations extend the…
The possible impact Sgr A East is having on the Galactic center has fueled speculation concerning its age and the energetics of the supernova explosion that produced it. We have carried out the first in-depth analysis of the remnant's…
The orbits of stars around Sgr A*, the Milky Way's supermassive black hole, provide a unique laboratory for testing its environment with unprecedented precision. In this work, we compute the apsidal precession induced by extended matter…
The Fermi bubbles are two giant bubbles in gamma rays lying above and below the Galactic center (GC). Despite numerous studies on the bubbles, their origin and emission mechanism remain elusive. Here we use a suite of hydrodynamic…
We aim at modelling small groups of young stars such as IRS 13N, 0.1 pc away from Sgr A*, which is suggested to contain a few embedded massive young stellar objects. We perform hydrodynamical simulations to follow the evolution of molecular…
We present three-dimensional hydrodynamic simulations of the interaction of a slow wind from an asymptotic giant branch(AGB) star and a jet blown by an orbiting companion. The jet or "Collimated Fast Wind" is assumed to originate from an…
The supermassive black hole Sgr A* at the center of the Galaxy is surrounded by two misaligned disks of young, massive stars extending from ~0.04 to 0.4 pc. The stellar surface density increases as ~ r^-2 towards Sgr A* but is truncated…
Recent work on the gas dynamics in the Galactic Center has improved our understanding of the accretion processes in galactic nuclei, particularly with regard to properties such as the specific angular momentum distribution, density, and…
We study the evolution of G2 in a \textit{Compact Source Scenario}, where G2 is the outflow from a low-mass central star moving on the observed orbit. This is done through 3D AMR simulations of the hydrodynamic interaction of G2 with the…
The Sagittarius B2 (Sgr B2) molecular cloud complex is an X-ray reflection nebula whose total emissions have continued to decrease since 2001 as it reprocesses one or more past energetic outbursts from the supermassive black hole…
IGR J18027-2016 is an obscured high-mass X-ray binary formed by a neutron star accreting from the wind of a supergiant companion with a $\sim$4.57 day orbital period. The source shows an asymmetric eclipse profile that remained stable…