MeerKAT view of Hickson Compact Groups II. Hi deficiency in the cores and surrounding regions
Journal article, 2025

Context. Hickson compact groups (HCGs) offer an ideal environment for investigating galaxy transformation as a result of interactions. It has been established that the evolutionary sequence of HCGs is marked by an intermediate stage characterised by a substantial amount of Hi in their intragroup medium (IGrM) in the form of tidal tails and bridges (phase 2), rapidly followed by a final stage in which no IGrM gas is found and i which their member galaxies are highly Hi deficient (phase 3). Aims. Despite numerous single-dish and interferometric Hi studies on the HCGs, a clear Hi picture of the groups within their large-scale environment still remains to be uncovered. Taking advantage of MeerKAT’s high column density sensitivity and large field of view, we aim to investigate the rapid transformation of HCGs from the intermediate to late phases, and establish a picture of their gas content variations in the context of their large-scale environments. Methods. We performed MeerKAT observations of six HCGs that were selected to represent the intermediate and late phases of the proposed evolutionary sequence. Combining the Hi observations with data from recent wide-field optical surveys, we evaluated the Hi deficiencies of galaxies in a ∼300 radius of the HCGs. Results. We find that galaxies surrounding both phases exhibit similar distributions in their gas content. Similarly, galaxies making up the cores of phase 2 HCGs are comparable to their neighbours in terms of Hi deficiencies. However, phase 3 groups are over an order of magnitude more deficient than their surroundings, supporting previous findings that late-phase HCG galaxies are more evolved than their large-scale environments.

galaxies: evolution

galaxies: interactions

intergalactic medium

Author

A. Sorgho

Spanish National Research Council (CSIC)

L. Verdes-Montenegro

Spanish National Research Council (CSIC)

R. Ianjamasimanana

Spanish National Research Council (CSIC)

Kelley Michelle Hess

Spanish National Research Council (CSIC)

Netherlands Institute for Radio Astronomy (ASTRON)

Chalmers, Space, Earth and Environment, Onsala Space Observatory

M. G. Jones

University of Arizona

M. Korsaga

Université Joseph Ki-Zerbo

Spanish National Research Council (CSIC)

J. Wang

Beijing University of Technology

Xuchen Lin

Beijing University of Technology

J. M. Solanes

University of Barcelona

M. E. Cluver

Swinburne University of Technology

J. M. Cannon

Macalester College

A. Bosma

Laboratoire d'Astrophysique de Marseille

E. Athanassoula

Laboratoire d'Astrophysique de Marseille

A. del Olmo

Spanish National Research Council (CSIC)

J. Perea

Spanish National Research Council (CSIC)

J. Moldon

Spanish National Research Council (CSIC)

T. Wiegert

Spanish National Research Council (CSIC)

S. Sánchez-Expósito

Spanish National Research Council (CSIC)

J. Garrido

Spanish National Research Council (CSIC)

R. García-Benito

Spanish National Research Council (CSIC)

G. I.G. Józsa

Max Planck Society

Rhodes University

S. Borthakur

Arizona State University

T. H. Jarrett

University of the Western Cape

University of Cape Town

B. Namumba

Spanish National Research Council (CSIC)

E. Pérez

Spanish National Research Council (CSIC)

J. Román

Complutense University

O. Smirnov

Rhodes University

Istituto nazionale di astrofisica (INAF)

South African Radio Astronomy Observatory (SARAO)

Min S. Yun

University of Massachusetts

Astronomy and Astrophysics

0004-6361 (ISSN) 1432-0746 (eISSN)

Vol. 696 A177

Subject Categories (SSIF 2025)

Astronomy, Astrophysics, and Cosmology

DOI

10.1051/0004-6361/202452995

Related datasets

HCG deficiency analysis: first version of the code [dataset]

URI: https://zenodo.org/records/14965528

More information

Latest update

5/5/2025 1