Browsing by Author "Ndaliso, Xola"

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    MeerKAT-derived h i kinematics and the baryonic Tully–Fisher relation in the x-ray luminous cluster Abell 3408
    (Oxford University Press, 2025) Elson, Ed; Ndaliso, Xola; Blecher, Tariq
    Significant advances in observational capabilities are continuously transforming our understanding of the dense environment of galaxy clusters and its impact on individual galaxies. Discerning between the intrinsic and the externally induced properties of galaxies, including their gas kinematics, is a key diagnostic in the field of galaxy evolution. In this paper, we present MeerKAT HI spectral line observations of the redshift z ∼ 0.042 galaxy cluster Abell 3408. A total of 64 galaxies are detected in HI in this X-ray luminous galaxy cluster (LX ∼ 3 × 1043 erg s−1). We model the H I morphology and gas kinematics of the individual galaxies, using a semi-automated pipeline based on CANNUBI and pyBBarolo. The pipeline was developed and tested as part of this study. Of the 64 galaxies detected in the cluster, we successfully modelled 16, while the remaining galaxies exhibit disturbed HI morphologies, insufficient angular or velocity resolution. We combine the galaxies with converged kinematic fits with 67 field galaxies from the MeerKAT spectral line survey early science data (⟨z⟩= 0.0435) to produce a measurement of the baryonic Tully–Fisher relation (bTFr) that encompasses a broader range of environment and provides a useful comparison. We find a slope (α = 3.66+0.32−0.28) for this relation, which is consistent with that found from the MeerKAT International GHz Tiered Extragalactic Exploration (MIGHTEE) survey bTFr derived from the same definition. Interestingly, HI detections of the Abell 3408 galaxy cluster galaxies are seen to extend the bTFr of the MIGHTEE sample, both in mass and velocity, despite their cluster environment.
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    A study of the nearby interacting galaxy pair NGC 1512/1510
    (University of Western Cape, 2020) Ndaliso, Xola; Elson, Ed; Glowacki, M.; Maartens, R.
    This work focuses on generating a new dynamical model of the nearby (9.5 Mpc) interacting galaxy system NGC 1512/1510. Neutral hydrogen (H i ) observations from the Australia Telescope Compact Array (ATCA) are used to model the dynamics of the main H i disk using two routines, the two and three-dimensional modeling techniques. For the two-dimensional modeling technique, we adopt ROTCUR which is based on fitting a tilted ring model onto the 2D velocity field of the galaxy. The three-dimensional modeling routine used is 3DBarolo, which is a recently developed algorithm of fitting 3D tilted ring model to the full data cube. We note that the 2D approach fails to model the inclination profile of NGC 1512. Thus, a new rotation curve is generated using the three-dimensional modeling routine only i.e. by fitting a 3D tilted ring model to the H i line data cube of NGC 1512/1510.