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Related papers: Galactic Centre stellar winds and Sgr A* accretion

200 papers

We develop a model for the wind properties of cool main-sequence stars, which comprises their wind ram pressures, mass fluxes, and terminal wind velocities. The wind properties are determined through a polytropic magnetised wind model,…

Astrophysics · Physics 2009-11-11 V. Holzwarth , M. Jardine

Young stars and planetary systems form in molecular clouds. For classical T Tauri stars (CTTS, F-K type precursors) the accretion disk does not reach down to the central star, but it is truncated near the co-rotation radius. The inner edge…

Solar and Stellar Astrophysics · Physics 2015-06-11 Hans Moritz Günther

Inspired by the excess soft X-ray emission recently detected in Green Pea galaxies, we model the soft X-ray emission (0.5 - 2.0 keV) of hot gas from star cluster winds. By combining individual star clusters, we estimate the soft X-ray…

Galactic superwinds may be driven by very hot outflows generated by overlapping supernovae within the host galaxy. We use the Chevalier & Clegg (CC85) wind model and the observed correlation between X-ray luminosities of galaxies and their…

Astrophysics of Galaxies · Physics 2015-06-17 Dong Zhang , Todd A. Thompson , Norman Murray , Eliot Quataert

Using synthetic absorption lines generated from 3D hydro-dynamical simulations we explore how the velocity of a starburst-driven galactic wind correlates with the star formation rate (SFR) and SFR density. We find strong correlations until…

Astrophysics of Galaxies · Physics 2017-07-24 Ryan Tanner , Gerald Cecil , Fabian Heitsch

We study the environment of Sgr A* using spectral and continuum observations with the ALMA and VLA. Our analysis of sub-arcsecond H30alpha, H39alpha, H52alpha and H56alpha line emission towards Sgr A* confirm the recently published broad…

High Energy Astrophysical Phenomena · Physics 2020-09-09 F. Yusef-Zadeh , M. Royster , M. Wardle , W. Cotton , D. Kunneriath , I. Heywood , J. Michail

Young massive stars warm up the large amount of gas and dust which condenses in their vicinity, exciting a forest of lines from different molecular species. Their line brightness is a diagnostic tool of the gas physical conditions locally,…

Astrophysics of Galaxies · Physics 2021-11-24 A. Sanna , A. Giannetti , M. Bonfand , L. Moscadelli , R. Kuiper , J. Brand , R. Cesaroni , A. Caratti o Garatti , T. Pillai , K. M. Menten

We explore the possibility that neutron stars accreting from the winds of main-sequence stellar companions account for a significant fraction of low-luminosity, hard X-ray sources (L_X <~ 10^35 ergs/s; 1-10 keV) in the Galaxy. This work was…

Astrophysics · Physics 2009-11-07 E. Pfahl , S. Rappaport , Ph. Podsiadlowski

The heavy mass loss observed in evolved asymptotic giant branch (AGB) stars is usually attributed to a two-stage process: atmospheric levitation by pulsation-induced shock waves, followed by radiative acceleration of newly formed dust…

Solar and Stellar Astrophysics · Physics 2015-06-15 Sara Bladh , Susanne Höfner , Walter Nowotny , Bernhard Aringer

Stellar winds from active solar type stars can play a crucial role in removal of stellar angular momentum and erosion of planetary atmospheres. However, major wind properties except for mass loss rates cannot be directly derived from…

Solar and Stellar Astrophysics · Physics 2016-02-17 Vladimir S. Airapetian , Arcadi V. Usmanov

Sagittarius A* (Sgr A*) is a compact radio source at the Galactic center. Observations have confirmed that its mass is approximately (4.1)*10$^{6}$ M$_{\odot}$, and Sgr A* is generally believed to be powered by gas accretion onto a…

High Energy Astrophysical Phenomena · Physics 2026-03-05 Shenyue Yin , Siming Liu

Accretion flow in a contracting magnetized isothermal cloud was studied using magnetohydrodynamical simulations and a nested grid technique. First, the interstellar magnetized cloud experiences a ``runaway collapse'' phase, in which the…

Astrophysics · Physics 2015-06-24 Kohji Tomisaka

Recent observations of the Galactic center in high-energy gamma-rays (above 0.1TeV) have opened up new ways to study this region, from understanding the emission source of these high-energy photons to constraining the environment in which…

We present the first results from a high resolution simulation with a focus on galactic wind driving for an isolated galaxy with a halo mass of $\sim 10^{11}$ M$_{\odot}$ (similar to the Large Magellanic Cloud) and a total gas mass of $\sim…

In this paper the jet model for the supermassive black hole candidate Sgr A* in the Center of the Galaxy is reviewed. The most recent model, with a reduced set of parameters, is able to account for all major radio properties of the source:…

Astrophysics · Physics 2007-05-23 Heino Falcke

abridged: We use XSCORT, together with the hydrodynamic accretion disc wind simulation from Proga & Kallman (2004), to calculate the impact that the accretion disk wind has on the X-ray spectrum from a 1E8 solar mass black hole Active…

Astrophysics · Physics 2011-02-11 N. J. Schurch , C. Done , D. Proga

High spatial resolution techniques have given valuable insights into the mass loss mechanism of AGB stars, which presumably involves a combination of atmospheric levitation by pulsation-induced shock waves and radiation pressure on dust.…

Solar and Stellar Astrophysics · Physics 2016-10-19 Susanne Höfner , Sara Bladh , Bernhard Aringer , Rajeev Ahuja

Hydrodynamic models for spherically-symmetric winds driven by young stellar clusters with a generalized Schuster stellar density profile are explored. For this we use both semi-analytic models and 1D numerical simulations. We determine the…

We examine the dependence of the wind-wind collision and subsequent X-ray emission from the massive WR+O star binary WR~22 on the acceleration of the stellar winds, radiative cooling, and orbital motion. Simulations were performed with…

High Energy Astrophysical Phenomena · Physics 2015-05-27 E. R. Parkin , E. Gosset

How T Tauri stars remain slowly rotating while still accreting material is a long-standing puzzle. Current models suggest that these stars may lose angular momentum through magnetospheric ejections of disk material (MEs) and…

Solar and Stellar Astrophysics · Physics 2025-04-30 Lukas Gehrig , Eric Gaidos , Laura Venuti , Ann Marie Cody , Neal J. Turner