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arXiv · 1710.09040

UGC 4703 interacting pair near to an isolated spiral galaxy NGC 2718: A Milky Way Magellanic Cloud analogue

Sanjaya Paudel·C. Sengupta
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Abstract

We present an analysis of physical and morphological properties of an interacting pair of dwarf galaxies UGC 4703 located at the vicinity of an isolated Milky-Way (MW) type spiral galaxy NGC 2718. Based on the comparison of physical and morphological properties with that of the Large and Small Magellanic Clouds (LMC and SMC), we report that the UGC 4703 pair-NGC 2718 system is probably an LMC-SMC-MW analogue. Located at a sky projected distance of 81 kpc from NGC 2718, we find that UGC 4703 is clearly interacting with its nearby smaller mass companion UGC 4703B forming a bridge of stellar stream between them. Total B-band luminosity of UGC 4703 and its companion is -17.75 and -16.25 mag, respectively. We obtained HI 21-cm line data of UGC 4703 using the GMRT to get a more detailed view of neutral hydrogen (HI) emission. The HI image revealed evidence of interaction between the dwarf galaxy pair but no extended emission, like Magellanic Stream (MS), was detected between NGC 2781 and the UGC 4703 dwarf pair. We also detected star-forming regions along the UGC 4703/ 4703B bridge with stellar mass exceeding 10$^{7}$ M$_{\odot}$. While comparing the optical and HI morphology of the interacting dwarf pairs (UGC 4703-4703B and LMC-SMC) we discuss possible difference in interaction histories of these systems.

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Sanjaya Paudel, C. Sengupta. 2017-10-25. UGC 4703 interacting pair near to an isolated spiral galaxy NGC 2718: A Milky Way Magellanic Cloud analogue. https://doi.org/10.3847/2041-8213/aa95bf

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