6–10 Jul 2026
University of the Western Cape
Africa/Johannesburg timezone
**Tours now open!** Registration is now closed - All registration payments are due before 23:39 SAST on 26 June.

MeerKAT HI reveals ram-pressure stripping in Abell 3408 galaxy cluster

7 Jul 2026, 14:40
20m
Lecture Hall C5 (University of the Western Cape)

Lecture Hall C5

University of the Western Cape

Oral Presentation Track D - Astrophysics & Space Science Astrophysics & Space Science

Speaker

Xola Ndaliso (University of the Witwatersrand)

Description

Galaxy clusters are laboratories for studying the interplay between the hot intra-cluster medium (ICM) and the galaxies embedded within it, offering key insights into the environmental processes driving galaxy evolution. We use X-ray and \hi spectral line observations of the \textit{z}~$\sim$~0.042 Abell 3408 galaxy cluster to investigate the influence of the hot X-ray emitting intra-cluster medium (ICM) on individual cluster members. The X-ray data were obtained with eROSITA during the performance-verification (PV) phase, and the \hi observations of 64 galaxies within this cluster were observed with MeerKAT. Through detailed imaging and surface brightness analysis, we identify two distinct X-ray emission clumps located in the south-east (SE) direction of the cluster, both within the radius \textit{R}$_{200}$. Three \hi galaxies detected with MeerKAT are found in the vicinity of one of these X-ray clumps. Notably, one of the galaxies shows signs of disturbed gas suppression \hi morphology, including an extended $\sim$ 200 kpc \hi tail. We carry out ram-pressure stripping analysis and find that this galaxy is indeed ram-pressure stripped. This extended \hi tail galaxy, along with three other galaxies, has a prominent X-ray counterpart. Lastly, we performed spectral analysis in the 0.3~–~9~keV energy range and determined a cluster temperature of \textit{k}$_B$T~=~2.37$^{+0.1}_{-0.1}$ keV, and metallicity \textit{Z}\textsubscript{$\odot$}~=~0.18$^{+0.02}_{-0.02}$. In the 0.3~–~2.3~keV energy band, the cluster's X-ray luminosity is measured to be \textit{L}\textsubscript{X}~=~2.54~$\times$~10$^{43}$~ergs\,s$^{-1}$.

Apply for student award at which level: PhD
Consent on use of personal information: Abstract Submission Yes, I ACCEPT

Author

Xola Ndaliso (University of the Witwatersrand)

Co-authors

Prof. Ed Elson (UWC) Prof. John Hughes (Rutgers University) Prof. Roger Deane (IDIA, Wits, UP)

Presentation materials

There are no materials yet.