MeerKAT-64 discovers wide-spread tidal debris in the nearby NGC 7232 galaxy group

Abstract

We report the discovery of large amounts of previously undetected cold neutral atomic hydrogen (\HI) around the core triplet galaxies in the nearby NGC~7232 galaxy group with MeerKAT. With a physical resolution of $\sim$1 kpc, we detect a complex web of low surface brightness \HI\ emission down to a 4$\sigma$ column density level of $\sim$1 $\times$ 10${}^{19}$ cm${}^{-2}$ (over 44 \kms ). The newly discovered H\,{\sc i} streams extend over $\sim$20 arcmin corresponding to 140~kpc in projection. This is $\sim$3 times the \HI\ extent of the galaxy triplet (52 kpc). The \HI\ debris has an \HI\ mass of $\sim$6.6 $\times 10^9$~M${}_{\odot }$, more than 50\% of the total \HI\ mass of the triplet. Within the galaxy triplet, NGC~7233 and NGC~7232 have lost a significant amount of \HI\ while NGC~7232B appears to have an excess of \HI. The \HI\ deficiency in NGC~7232 and NGC~7233 indicates that galaxy-galaxy interaction in the group concentrates on this galaxy pair while the other disc galaxies have visited them over time. In comparison to the AMIGA sample of isolated galaxies we find that with regards to its total \HI\ mass the NGC~7232/3 galaxy triplet is not \HI\ deficient. Despite the many interactions associated to the triplet galaxies, no \HI\ seems to have been lost from the group (yet).

arXiv comment17 pages, 11 figures, accepted for publication in MNRAS

References in corpus (49)

• Overview of the DESI Legacy Imaging Surveys
• WSClean: an implementation of a fast, generic wide-field imager for radio astronomy
• HyperLEDA. III. The catalogue of extragalactic distances
• The HIPASS Catalogue - I. Data Presentation
• The 1000 Brightest HIPASS Galaxies: HI Properties
• The Arecibo Legacy Fast ALFA Survey: The ALFALFA Extragalactic HI Source Catalog
• Galaxy ecology: groups and low-density environments in the SDSS and 2dFGRS
• The Properties of Poor Groups of Galaxies: I. Spectroscopic Survey and Results
• Galaxy and Mass Assembly (GAMA): The GAMA Galaxy Group Catalogue (G3Cv1)
• The HI Content of Spirals. II. Gas Deficiency in Cluster Galaxies
• An optimized algorithm for multi-scale wideband deconvolution of radio astronomical images
• Where is the Neutral Atomic Gas in Hickson Groups?
• SoFiA: a flexible source finder for 3D spectral line data
• WALLABY -- An SKA Pathfinder HI Survey
• A Universal Neutral Gas Profile for Nearby Disk Galaxies
• Revival of the magnetar PSR J1622-4950: observations with MeerKAT, Parkes, XMM-Newton, Swift, Chandra, and NuSTAR
• Missing Mass in Collisional Debris from Galaxies
• From Tidal Dwarf Galaxies to Satellite Galaxies
• The AMIGA project. I. Optical characterization of the CIG catalog
• CubiCal - Fast radio interferometric calibration suite exploiting complex optimisation
• The Local Volume HI Survey (LVHIS)
• The AMIGA sample of isolated galaxies IX. Molecular gas properties
• Quenching of Star Formation in SDSS Groups: Centrals, Satellites, and Galactic Conformity
• Evolution in the H I Gas Content of Galaxy Groups: Pre-Processing and Mass Assembly in the Current Epoch
• Overview on spectral line source finding and visualisation
• Discovery of a giant HI tail in the galaxy group HCG 44
• SDSS-IV MaNGA: The Spatial Distribution of Star Formation and its Dependence on Mass, Structure and Environment
• The matter distribution in the local Universe as derived from galaxy groups in SDSS DR12 and 2MRS
• HIPASS Detection of an Intergalactic Gas Cloud in the NGC 2442 Group
• Star formation in galaxies falling into clusters along supercluster-scale filaments
• HI content in galaxies in loose groups
• Massive HI clouds with no optical counterparts as high-density regions of intragroup HI rings and arcs
• The AMIGA sample of isolated galaxies XIII. The HI content of an almost "nurture free" sample
• Dark galaxies or tidal debris? Kinematical clues to the origin of massive isolated HI clouds
• A MeerKAT view of pre-processing in the Fornax A group
• WALLABY Early Science - II. The NGC 7232 galaxy group
• The Neutral Hydrogen Content of Fornax Cluster Galaxies
• The Vela Cloud: A Giant HI Anomaly in the NGC 3256 Group
• HI imaging of galaxies in X-ray bright groups
• WALLABY Early Science -- IV. ASKAP HI imaging of the nearby galaxy IC 5201
• The frequency and properties of young tidal dwarf galaxies in nearby gas-rich groups
• HI in Group Interactions: HCG 44
• The complex X-ray morphology of NGC 7618: A major group-group merger in the local Universe?
• Advanced Data Visualization in Astrophysics: the X3D Pathway
• Evolution of compact groups from intermediate to final stages: A case study of the HI content of HCG 16
• Structure and Star Formation in NGC 925
• HI debris in the IC 1459 galaxy group
• Evolution of galaxies in groups in the Coma Supercluster
• Hydrogen tails, plumes, clouds and filaments

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