Revealing A Head-on Major Merger in the Nearby NGC 6338 Group with Chandra and VLA observations. (arXiv:1901.08769v1 [astro-ph.GA])
<a href="http://arxiv.org/find/astro-ph/1/au:+Wang_Y/0/1/0/all/0/1">Yu Wang</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Lui_F/0/1/0/all/0/1">Fuyao Lui</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Shen_Z/0/1/0/all/0/1">Zhiqiang Shen</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Wang_J/0/1/0/all/0/1">Jingying Wang</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Hu_D/0/1/0/all/0/1">Dan Hu</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Xu_H/0/1/0/all/0/1">Hai-Guang Xu</a>
By analyzing the Chandra archival data of the nearby NGC 6338 galaxy group,
we identify two X-ray bright clumps (N-clump and S-clump) within the central
100 kpc, and detect an arc-like X-ray brightness discontinuity at the south
boundary of the N-clump, which is defined as a cold front with a gas flow Mach
number of M<0.8. Furthermore, at the north-east boundary of the S-clump
(dominated by galaxy NGC 6338) another X-ray edge is detected that corresponds
to a weaker cold front. Therefore, the two clumps are approaching each other
approximately from opposite directions, and the group is undergoing a head-on
collision that is in a stage of pre-core passage. This merger scenario is also
supported by the study of the line-of-sight velocity distribution of the group
member galaxies. The merger mass ratio is about 1:1.8 as estimated from the
central gas temperature of the two clumps, which suggests the merger is most
likely to be a major merger. We also analyze the VLA 1.4 and 4.9 GHz radio
data, but we do not detect any extended radio emission that is associated with
the merger.
By analyzing the Chandra archival data of the nearby NGC 6338 galaxy group,
we identify two X-ray bright clumps (N-clump and S-clump) within the central
100 kpc, and detect an arc-like X-ray brightness discontinuity at the south
boundary of the N-clump, which is defined as a cold front with a gas flow Mach
number of M<0.8. Furthermore, at the north-east boundary of the S-clump
(dominated by galaxy NGC 6338) another X-ray edge is detected that corresponds
to a weaker cold front. Therefore, the two clumps are approaching each other
approximately from opposite directions, and the group is undergoing a head-on
collision that is in a stage of pre-core passage. This merger scenario is also
supported by the study of the line-of-sight velocity distribution of the group
member galaxies. The merger mass ratio is about 1:1.8 as estimated from the
central gas temperature of the two clumps, which suggests the merger is most
likely to be a major merger. We also analyze the VLA 1.4 and 4.9 GHz radio
data, but we do not detect any extended radio emission that is associated with
the merger.
http://arxiv.org/icons/sfx.gif
