Outskirts of Abell 1795: Probing gas clumping in the intracluster medium

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216224%3A14310%2F23%3A00134409" target="_blank" >RIV/00216224:14310/23:00134409 - isvavai.cz</a>

Result on the web

<a href="https://www.aanda.org/articles/aa/full_html/2023/10/aa47201-23/aa47201-23.html" target="_blank" >https://www.aanda.org/articles/aa/full_html/2023/10/aa47201-23/aa47201-23.html</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1051/0004-6361/202347201" target="_blank" >10.1051/0004-6361/202347201</a>

Result language

angličtina

Original language name

Outskirts of Abell 1795: Probing gas clumping in the intracluster medium

Original language description

Contact. The outskirts of galaxy clusters host complex interactions between the intracluster and circumcluster media. During the evolution of clusters, ram-pressure stripped gas clumps from infalling substructures break the uniformity of the gas distribution, potentially leading to observational biases at large radii. However, assessing the contribution of gas clumping poses observational challenges and requires robust X-ray measurements in the background-dominated regime of the cluster outskirts. Aims. The main objectives of this study are to isolate faint gas clumps from field sources and from the diffuse emission in the Abell 1795 galaxy cluster, then to probe their impact on the observed surface brightness and thermodynamic profiles. Methods. We performed an imaging analysis on deep Chandra ACIS-I observations of the Abell 1795 cluster outskirts, extending out to ~1.5r200 with full azimuthal coverage. We built the 0.7 - 2.0 keV surface brightness distribution from the adaptively binned image of the diffuse emission and looked for clumps in the form of &gt; + 2σ surface brightness outliers. Our classification of the clump candidates was based primarily on Chandra and SDSS data. Benefiting from the point source list resolved by Chandra, we extracted the thermodynamic profiles of the intracluster medium from the associated Suzaku XIS data out to r200 using multiple point source and clump candidate removal approaches. Results. We identified 24 clump candidates in the Abell 1795 field, most of which are likely to be associated with background objects, including active galactic nuclei, galaxies, and clusters or groups of galaxies, as opposed to intrinsic gas clumps. These sources had minimal impact on the surface brightness and thermodynamic profiles of the cluster emission. After correcting for clump candidates, the measured entropy profile still deviates from a pure gravitational collapse, suggesting complex physics at play in the outskirts, which may include potential electron- ion non-equilibrium and non-thermal pressure support.

Czech name

—

Czech description

—

Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

10308 - Astronomy (including astrophysics,space science)

Project

<a href="/en/project/GX21-13491X" target="_blank" >GX21-13491X: Exploring the Hot Universe and Understanding Cosmic Feedback</a><br>

Continuities

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Publication year

2023

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Astronomy and Astrophysics

ISSN

0004-6361

e-ISSN

1432-0746

Volume of the periodical

678

Issue of the periodical within the volume

October 2023

Country of publishing house

FR - FRANCE

Number of pages

23

Pages from-to

1-23

UT code for WoS article

001192036800001

EID of the result in the Scopus database

2-s2.0-85175057398