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arXiv · 1907.12556

WALLABY Early Science -- IV. ASKAP HI imaging of the nearby galaxy IC 5201

D. Kleiner·B. S. Koribalski·P. Serra·M. T. Whiting·T. Westmeier·O. I. Wong·P. Kamphuis·A. Popping·G. Bekiaris·A. Elagali·B. -Q. For·K. Lee-Waddell·J. P. Madrid·T. N. Reynolds·J. Rhee·L. Shao·L. Staveley-Smith·J. Wang·C. S. Anderson·J. Collier·S. M. Ord·M. A. Voronkov
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Abstract

We present a Wide-field ASKAP L-Band Legacy All-sky Blind surveY (WALLABY) study of the nearby ($v_{\rm sys}$ = 915 km s$^{-1}$) spiral galaxy IC 5201 using the Australian Square Kilometre Array Pathfinder (ASKAP). IC 5201 is a blue, barred spiral galaxy that follows the known scaling relations between stellar mass, SFR, HI mass and diameter. We create a four-beam mosaicked HI image cube, from 175 hours of observations made with a 12-antenna sub-array. The RMS noise level of the cube is 1.7 mJy beam$^{-1}$ per channel, equivalent to a column density of $N_{\rm HI}$ = 1.4 $\times$ 10$^{20}$ cm$^{-2}$ over 25 km s$^{-1}$. We report 9 extragalactic HI detections $-$ 5 new HI detections including the first velocity measurements for 2 galaxies. These sources are IC 5201, 3 dwarf satellite galaxies, 2 galaxies and a tidal feature belonging to the NGC 7232/3 triplet and 2 potential infalling galaxies to the triplet. There is evidence of a previous tidal interaction between IC 5201 and the irregular satellite AM 2220$-$460. A close fly-by is likely responsible for the asymmetric optical morphology of IC 5201 and warping its disc, resulting in the irregular morphology of AM 2220$-$460. We quantify the HI kinematics of IC 5201, presenting its rotation curve as well as showing that the warp starts at 14 kpc along the major axis, increasing as a function of radius with a maximum difference in position angle of 20$^\circ$. There is no evidence of stripped HI, triggered or quenched star formation in the system as measured using DECam optical and $GALEX$ UV photometry.

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D. Kleiner, B. S. Koribalski, P. Serra, M. T. Whiting, T. Westmeier, O. I. Wong, P. Kamphuis, A. Popping, G. Bekiaris, A. Elagali, B. -Q. For, K. Lee-Waddell, J. P. Madrid, T. N. Reynolds, J. Rhee, L. Shao, L. Staveley-Smith, J. Wang, C. S. Anderson, J. Collier, S. M. Ord, M. A. Voronkov. 2019-07-29. WALLABY Early Science -- IV. ASKAP HI imaging of the nearby galaxy IC 5201. https://doi.org/10.1093/mnras%2Fstz2063

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