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arXiv · 0904.4908

HI content and star formation in the interacting galaxy Arp86

Chandreyee Sengupta·K. S. Dwarakanath·D. J. Saikia
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Abstract

We present the results of Giant Metrewave Radio Telescope (GMRT) observations of the interacting system Arp86 in both neutral atomic hydrogen, HI, and in radio continuum at 240, 606 and 1394 MHz. In addition to HI emission from the two dominant galaxies, NGC7752 and NGC7753, these observations show a complex distribution of HI tails and bridges due to tidal interactions. The regions of highest column density appear related to the recent sites of intense star formation. HI column densities $\sim1-$1.5 $\times10^{21}$ cm$^{-2}$ have been detected in the tidal bridge which is bright in Spitzer image as well. We also detect HI emission from the galaxy 2MASX J23470758+2926531, which is shown to be a part of this system. We discuss the possibility that this could be a tidal dwarf galaxy. The radio continuum observations show evidence of a non-thermal bridge between NGC7752 and NGC7753, and a radio source in the nuclear region of NGC7753 consistent with it having a LINER nucleus.

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Chandreyee Sengupta, K. S. Dwarakanath, D. J. Saikia. 2009-04-30. HI content and star formation in the interacting galaxy Arp86. https://doi.org/10.1111/j.1365-2966.2009.14968.x

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