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Related papers: Non-equilibrium Ionization States Within Galactic …

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The Intergalactic Medium (IGM) contains $>$50% of the baryonic mass of the Universe, yet the mechanisms responsible for keeping the IGM ionized has not been fully explained. Hence, we investigate ion abundances from the largest blind QSO…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-04 Brad Koplitz , Anjali Ramesh , Sanchayeeta Borthakur

Ionized outflows in Active Galactic Nuclei (AGN) are thought to influence their nuclear and local galactic environment. However, the distance of the outflows with respect to the central engine is poorly constrained, which limits our…

High Energy Astrophysical Phenomena · Physics 2017-11-22 Junjie Mao , J. S. Kaastra , M. Mehdipour , A. J. J. Raassen , Liyi Gu , J. M. Miller

We investigate a non-equilibrium ionization state and an electron-ion two-temperature structure of the intracluster medium (ICM) in merging galaxy clusters using a series of N-body and hydrodynamic simulations. Mergers with various sets of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Takuya Akahori , Kohji Yoshikawa

Outflows in starburst galaxies driven by thermal-mechanical energy, cosmic rays and their mix are investigated with 1D and 2D hydrodynamic simulations. We show that these outflows could reach a stationary state, after which their…

Astrophysics of Galaxies · Physics 2021-10-04 B. P. Brian Yu , Ellis R. Owen , Kuo-Chuan Pan , Kinwah Wu , Ignacio Ferreras

Nonequilibrium (time-dependent) cooling rates and ionization state calculations are presented for low-density gas enriched with heavy elements (metals) and photoionized by external ultraviolet/X-ray radiation. We consider a wide range of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Evgenii O. Vasiliev

We present spatially-resolved measurements of the ionized gas masses and mass outflow rates for six low-redshift ($z \leq$ 0.02) active galaxies. In this study, we expand our sample to galaxies with more complex gas kinematics modeled as…

We investigate the ionic column density variability of the ionized outflows associated with NGC$\sim$7469, to estimate their location and power. This could allow a better understanding of galactic feedback of AGNs to their host galaxies.…

Outflows from active galactic nuclei (AGN) are one of the fundamental mechanisms by which the central supermassive black hole interacts with its host galaxy. Detected in $\ge 50\%$ of nearby AGN, these outflows have been found to carry…

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 molecular gas in star-forming galaxies. These catastrophically…

Astrophysics of Galaxies · Physics 2022-09-30 A. Danehkar , M. S. Oey , W. J. Gray

The various ionization mechanisms at play in active galactic nuclei (AGN) and quasars have been well studied, but relatively little has been done to separately investigate the contributions of these ionization mechanisms within the host…

Astrophysics of Galaxies · Physics 2019-08-14 Jason T. Hinkle , Sylvain Veilleux , David S. N. Rupke

Powerful outflows are thought to play a critical role in galaxy evolution and black hole growth. We present the first large-scale systematic study of ionised outflows in paired galaxies and post-mergers compared to a robust control sample…

The circumgalactic medium (CGM) of nearby star-forming galaxies show clear indications of \ion{O}{6} absorption accompanied by little to no \ion{N}{5} absorption. This unusual spectral signature, accompanied by absorption from lower…

Astrophysics of Galaxies · Physics 2018-09-17 Edward Buie , William Gray , Evan Scannapieco

We analyse the distribution and origin of OVI in the Circumgalactic Medium (CGM) of dark-matter haloes of $\sim 10^{12}$ M$_\odot$ at $z\sim1$ in the VELA cosmological zoom-in simulations. We find that the OVI in the inflowing cold streams…

We present an updated model of the cosmic ionizing background from the UV to the X-rays. Relative to our previous model (Faucher-Giguere et al. 2009), the new model provides a better match to a large number of up-to-date empirical…

Cosmology and Nongalactic Astrophysics · Physics 2020-02-05 C. -A. Faucher-Giguere

We compare X-ray and UV spectroscopic observations of NGC 5548. Both data sets show O VI absorption troughs associated with the AGN outflow from this galaxy. We find that the robust lower limit on the column density of the O VI X-ray trough…

We consider a model of the circumgalactic medium (CGM) in which feedback maintains a constant ratio of cooling time to freefall time throughout the halo, so that the entire CGM is marginally unstable to multiphase condensation. This…

Astrophysics of Galaxies · Physics 2021-09-15 Manami Roy , Biman B. Nath , G. M. Voit

We extend our time-dependent hydrogen ionization simulations of diffuse ionized gas to include metals important for collisional cooling and diagnostic emission lines. The combination of heating from supernovae and time-dependent collisional…

Astrophysics of Galaxies · Physics 2024-11-12 Lewis McCallum , Kenneth Wood , Robert Benjamin , Dhanesh Krishnarao , Bert Vandenbroucke

We investigate models of self-consistent chemical enrichment of the intergalactic medium (IGM) from z=6 to 1.5, based on hydrodynamic simulations of structure formation that incorporate galactic outflows. Our main result is that outflow…

Astrophysics · Physics 2009-08-21 Benjamin D. Oppenheimer , Romeel Davé

Thermal energies deposited by OB stellar clusters in starburst galaxies lead to the formation of galactic superwinds. Multi-wavelength observations of starburst-driven superwinds pointed at complex thermal and ionization structures which…

Astrophysics of Galaxies · Physics 2023-02-21 A. Danehkar , M. S. Oey , W. J. Gray

We present computations of the ionization structure and metal-absorption properties of thermally conductive interface layers that surround evaporating warm spherical clouds, embedded in a hot medium. We rely on the analytical formalism of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Orly Gnat , Amiel Sternberg , Christopher F. McKee