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The importance of feedback (radiative and mechanical) from massive black holes at the centers of elliptical galaxies is not in doubt, given the well established relation among black hole mass and galaxy optical luminosity. Here, with the…

星系天体物理 · 物理学 2015-05-27 L. Ciotti , J. P. Ostriker

We present a physically motivated model for the early co-evolution of massive spheroidal galaxies and active nuclei at their centers. Within dark matter halos, forming at the rate predicted by the canonical hierarchical clustering scenario,…

天体物理学 · 物理学 2009-11-10 Gian Luigi Granato , Gianfranco De Zotti , Laura Silva , Alessandro Bressan , Luigi Danese

The current understanding of galaxy formation is that it proceeds in a 'bottom up' way, with the formation of small clumps of gas and stars that merge hierarchically until giant galaxies are built up. The baryonic gas loses the thermal…

天体物理学 · 物理学 2009-11-16 Masao Mori , Masayuki Umemura

In many clusters of galaxies, the cooling time at the core of the intracluster medium is much less than the age of the system, suggesting that the the gas should continually lose energy by radiation. Simple thermodynamic arguments then…

The existence of hot, X-ray luminous gaseous coronae surrounding present day L* galaxies is a generic prediction of galaxy formation theory in the cold dark matter cosmogony. While extended X-ray emission has been known to exist around…

宇宙学与河外天体物理 · 物理学 2010-11-10 Robert A. Crain , Ian G. McCarthy , Joop Schaye , Carlos S. Frenk , Tom Theuns

In massive primordial galaxies, the gas may directly collapse and form a single central massive object if cooling is suppressed. Line cooling by molecular hydrogen can be suppressed in the presence of a strong soft-ultraviolet radiation…

宇宙学与河外天体物理 · 物理学 2015-05-18 Dominik R. G. Schleicher , Marco Spaans , Simon C. O. Glover

Galaxy nuclei are a unique laboratory to study gas flows. High-resolution imaging of the gas flows in galactic nuclei are instrumental in the study of the fueling and the feedback of star formation and nuclear activity in nearby galaxies.…

星系天体物理 · 物理学 2017-01-11 Santiago Garcia-Burillo

We present a multi-wavelength study of the interstellar medium in eight nearby, X-ray and optically bright, giant elliptical galaxies. Using Herschel PACS, we map the cold gas in the lines of [CII], [OI], and [OIb]. Additionally, we present…

I begin by summarizing the evidence that there is a close relationship between the evolution of galaxies and supermassive black holes. They evidently share a common fuel source, and feedback from the black hole may be needed to suppress…

天体物理学 · 物理学 2015-05-13 T. M. Heckman

We consider the early universe at temperatures close to the fundamental scale of gravity (M_D << M_Planck) in models with extra dimensions. At such temperatures a small fraction of particles will experience transplanckian collisions that…

高能物理 - 理论 · 物理学 2010-01-26 Monica Borunda , Manuel Masip

Expanding X-ray cavities observed in hot gas atmospheres of many galaxy groups and clusters generate shock waves and turbulence that are primary heating mechanisms required to avoid uninhibited radiatively cooling flows which are not…

星系天体物理 · 物理学 2015-06-23 Fabrizio Brighenti , William G. Mathews , Pasquale Temi

Using numerical techniques we studied the global stability of cooling flows in giant elliptical galaxies. As an initial equilibrium state we choose the hydrostatic gas recycling model (Kritsuk 1996). Non-equilibrium radiative cooling,…

天体物理学 · 物理学 2009-10-30 A. Kritsuk , H. Boehringer , E. Mueller

We study the chemo-dynamical evolution of elliptical galaxies and their hot X-ray emitting gas using high-resolution cosmological simulations. Our Tree N-body/SPH code includes a self-consistent treatment of radiative cooling, star…

天体物理学 · 物理学 2016-01-27 Daisuke Kawata , Brad K. Gibson

The recent {\em ASCA} results show that the iron abundance of the X-ray gas of elliptical galaxies is less than the solar abundance ($Z_{\sun}$). The observed low iron abundance is inconsistent with the predictions of the previous chemical…

天体物理学 · 物理学 2009-10-28 Y. Fujita , J. Fukumoto , K. Okoshi

The standard treatment of cooling in Cold Dark Matter halos assumes that all of the gas within a ``cooling radius'' cools and contracts monolithically to fuel galaxy formation. Here we take into account the expectation that the hot gas in…

天体物理学 · 物理学 2010-04-06 Ariyeh H. Maller , James S. Bullock

The radiative cooling timescales at the centers of hot atmospheres surrounding elliptical galaxies, groups, and clusters are much shorter than their ages. Therefore, hot atmospheres are expected to cool and to form stars. Cold gas and star…

宇宙学与河外天体物理 · 物理学 2015-06-04 B. R. McNamara , P. E. J. Nulsen

We study the chemodynamical evolution of elliptical galaxies and their X-ray and optical properties using high-resolution cosmological simulations. Our Tree N-body/SPH code includes a self-consistent treatment of radiative cooling, star…

天体物理学 · 物理学 2009-11-10 Daisuke Kawata , Brad K. Gibson

Black hole accretion flows can be divided into two broad classes: cold and hot. Cold accretion flows, which consist of cool optically thick gas, are found at relatively high mass accretion rates. Prominent examples are the standard thin…

高能天体物理现象 · 物理学 2015-06-18 Feng Yuan , Ramesh Narayan

I study the possibility that a cooling flow (CF) exists at the main phase of super massive black hole (SMBH) growth during galaxy formation. To ensure that jets launched by the SMBH efficiently expel gas from the galaxy, as is required by…

宇宙学与河外天体物理 · 物理学 2015-05-14 Noam Soker

We describe 2D gasdynamical models of jets that carry mass as well as energy to the hot gas in galaxy clusters. These flows have many attractive attributes for solving the galaxy cluster cooling flow problem: Why the hot gas temperature and…

天体物理学 · 物理学 2009-11-11 Fabrizio Brighenti , William G. Mathews