Constraining the accretion flow density profile near Sgr A* using the L′-band emission of the S2 star

  title={Constraining the accretion flow density profile near Sgr A* using the L′-band emission of the S2 star},
  author={S. Elaheh Hosseini and Michal Zaja{\vc}ek and Andreas Eckart and Nadeen B. Sabha and Lucas Labadie},
  journal={Astronomy \& Astrophysics},
Context. The density of the ambient medium around a supermassive black hole (SMBH) and the way it varies with distance plays an important role in our understanding of the inflow-outflow mechanisms in the Galactic centre (GC). This dependence is often fitted by spherical power-law profiles based on observations in the X-ray, infrared (IR), submillimetre (submm), and radio domains. Aims. Nevertheless, the density profile is poorly constrained at the intermediate scales of 1000 Schwarzschild radii… 

Doppler Boosting of the S-stars in the Galactic Center

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The spectra of active galactic nuclei exhibit broad-emission lines that presumably originate in the broad-line region (BLR) with gaseous-dusty clouds in a predominantly Keplerian motion around the

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Prepared for submission to JCAP

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Several publications highlight the importance of the observations of bow shocks to learn more about the surrounding interstellar medium and radiation field. We revisit the most prominent dusty and



Near- and Mid-infrared Observations in the Inner Tenth of a Parsec of the Galactic Center Detection of Proper Motion of a Filament Very Close to Sgr A*

We analyze the gas and dust emission in the immediate vicinity of the supermassive black hole Sgr A* at the Galactic center (GC) with the ESO Very Large Telescope (Paranal/Chile) instruments SINFONI

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1. Accretion as a source of energy 2. Gas dynamics 3. Plasma concepts 4. Accretions in binary systems 5.Accretion discs in active galactic nuclei 6. Accrete on to a compact object 7. Active galacticuclei 8. Thick discs 9. Acc diffusion 10. thick discs 11. accretion flows.

Herbig-Haro Flows and the Birth of Stars; IAU Symposium No. 182

Using close stars as probes of hot accretion flow in Sgr A

The extremely hot and tenuous accretion flow in the immediate vicinity of Sgr A ∗ is believed to be invisible (too dim) in the X-ray band, except for short X-ray flares. Here we point out that during

2018a, A&A, 615

  • A&A,
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S62 on a 9.9 yr Orbit around SgrA*

We present the Keplerian orbit of S62 around the supermassive black hole Sagittarius A* (SgrA*) in the center of our Galaxy. We monitor this S-star cluster member over more than a full orbit around

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We have carried out Very Large Array (VLA) continuum observations to study the variability of Sgr A* at 43 GHz (λ=7mm) and 22 GHz (λ=13mm). A low level of flare activity has been detected with a

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