Scaling relations for dark matter core density and radius from Chandra X-ray cluster sample

ABSTRACT We explore the persistence of the alignment of brightest cluster galaxies (BCGs) with their local environment. We find that a significant fraction of BCGs do not coincide with the centroid of the X-ray gas distribution and/or show peculiar velocities (they are not at rest with respect to the cluster mean). Despite this, we find that BCGs are generally aligned with the cluster mass distribution even when they have significant offsets from the X-ray centre and significant peculiar velocities. The large offsets are not consistent with simple theoretical models. To account for these observations BCGs must undergo mergers preferentially along their major axis, the main infall direction. Such BCGs may be oscillating within the cluster potential after having been displaced by mergers or collisions, or the dark matter halo itself may not yet be relaxed.

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Clustering dependence of Chandra COSMOS Legacy AGN on host galaxy properties

Proceedings of the International Astronomical Union ◽

10.1017/s1743921320002987 ◽

2019 ◽

Vol 15 (S356) ◽

pp. 226-226

Author(s):

Viola Allevato

Keyword(s):

Dark Matter ◽

Formation Rate ◽

Stellar Mass ◽

Active Galaxies ◽

Host Galaxy ◽

Mass Star ◽

Mass Relation ◽

Dark Matter Halos ◽

X Ray

AbstractThe presence of a super massive BH in almost all galaxies in the Universe is an accepted paradigm in astronomy. How these BHs form and how they co-evolve with the host galaxy is one of the most intriguing unanswered problems in modern Cosmology and of extreme relevance to understand the issue of galaxy formation. Clustering measurements can powerfully test theoretical model predictions of BH triggering scenarios and put constraints on the typical environment where AGN live in, through the connection with their host dark matter halos. In this talk, I will present some recent results on the AGN clustering dependence on host galaxy properties, such as galaxy stellar mass, star formation rate and specific BH accretion rate, based on X-ray selected Chandra COSMOS Legacy Type 2 AGN. We found no significant AGN clustering dependence on galaxy stellar mass and specif BHAR for Type 2 COSMOS AGN at mean z ∼ 1.1, with a stellar - halo mass relation flatter than predicted for non active galaxies in the Mstar range probed by our sample. We also observed a negative clustering dependence on SFR, with AGN hosting halo mass increasing with decreasing SFR. Mock catalogs of active galaxies in hosting dark matter halos with logMh[Msun] > 12.5, matched to have the same X-ray luminosity, stellar mass and BHAR of COSMOS AGN predict the observed Mstar - Mh, BHAR - Mh and SFR-Mh relations, at z ∼ 1.

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Supermassive Black Hole feedback in early type galaxies

Proceedings of the International Astronomical Union ◽

10.1017/s1743921320004081 ◽

2020 ◽

Vol 15 (S359) ◽

pp. 119-125

Author(s):

W. Forman ◽

C. Jones ◽

A. Bogdan ◽

R. Kraft ◽

E. Churazov ◽

...

Keyword(s):

Dark Matter Halo ◽

Scaling Relations ◽

Radio Sources ◽

Early Type ◽

X Ray ◽

Galaxy Groups ◽

Sufficient Energy ◽

The Galaxy ◽

Simple Scaling ◽

Halo Masses

AbstractOptically luminous early type galaxies host X-ray luminous, hot atmospheres. These hot atmospheres, which we refer to as coronae, undergo the same cooling and feedback processes as are commonly found in their more massive cousins, the gas rich atmospheres of galaxy groups and galaxy clusters. In particular, the hot coronae around galaxies radiatively cool and show cavities in X-ray images that are filled with relativistic plasma originating from jets powered by supermassive black holes (SMBH) at the galaxy centers. We discuss the SMBH feedback using an X-ray survey of early type galaxies carried out using Chandra X-ray Observatory observations. Early type galaxies with coronae very commonly have weak X-ray active nuclei and have associated radio sources. Based on the enthalpy of observed cavities in the coronae, there is sufficient energy to “balance” the observed radiative cooling. There are a very few remarkable examples of optically faint galaxies that are 1) unusually X-ray luminous, 2) have large dark matter halo masses, and 3) have large SMBHs (e.g., NGC4342 and NGC4291). These properties suggest that, in some galaxies, star formation may have been truncated at early times, breaking the simple scaling relations.

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The central dark matter content of early-type galaxies: scaling relations and connections with star formation histories

Monthly Notices of the Royal Astronomical Society ◽

10.1111/j.1365-2966.2010.16710.x ◽

2010 ◽

pp. no-no ◽

Cited By ~ 26

Author(s):

Nicola R. Napolitano ◽

Aaron J. Romanowsky ◽

Crescenzo Tortora

Keyword(s):

Dark Matter ◽

Star Formation ◽

Matter Content ◽

Scaling Relations ◽

Early Type ◽

Star Formation Histories

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An X-ray spectroscopic search for dark matter in the Perseus cluster with Suzaku

Publications of the Astronomical Society of Japan ◽

10.1093/pasj/psu156 ◽

2015 ◽

Vol 67 (2) ◽

Cited By ~ 37

Author(s):

Takayuki Tamura ◽

Ryo Iizuka ◽

Yoshitomo Maeda ◽

Kazuhisa Mitsuda ◽

Noriko Y. Yamasaki

Keyword(s):

Dark Matter ◽

X Ray ◽

Perseus Cluster

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FORMATION OF DARK MATTER HALOES IN A HOMOGENEOUS DARK ENERGY UNIVERSE

International Journal of Modern Physics D ◽

10.1142/s0218271810017561 ◽

2010 ◽

Vol 19 (08n10) ◽

pp. 1397-1403

Author(s):

L. MARASSI

Keyword(s):

Dark Matter ◽

Dark Energy ◽

Large Scale ◽

State Parameter ◽

Mass Function ◽

Accelerated Expansion ◽

X Ray ◽

Energy Models ◽

Dark Energy Component ◽

Standard Press

Several independent cosmological tests have shown evidences that the energy density of the universe is dominated by a dark energy component, which causes the present accelerated expansion. The large scale structure formation can be used to probe dark energy models, and the mass function of dark matter haloes is one of the best statistical tools to perform this study. We present here a statistical analysis of mass functions of galaxies under a homogeneous dark energy model, proposed in the work of Percival (2005), using an observational flux-limited X-ray cluster survey, and CMB data from WMAP. We compare, in our analysis, the standard Press–Schechter (PS) approach (where a Gaussian distribution is used to describe the primordial density fluctuation field of the mass function), and the PL (power–law) mass function (where we apply a non-extensive q-statistical distribution to the primordial density field). We conclude that the PS mass function cannot explain at the same time the X-ray and the CMB data (even at 99% confidence level), and the PS best fit dark energy equation of state parameter is ω = -0.58, which is distant from the cosmological constant case. The PL mass function provides better fits to the HIFLUGCS X-ray galaxy data and the CMB data; we also note that the ω parameter is very sensible to modifications in the PL free parameter, q, suggesting that the PL mass function could be a powerful tool to constrain dark energy models.

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