NGC 3627: a galaxy-dwarf collision?

Abstract

Group galaxies very often show distinct signs of interaction with both companion galaxies and the intragroup medium. X-ray observations are particularly helpful because they provide information on the temperatures and the densities of the hot gas in galaxies and intergalactic space. This can put important constraints on the nature and timescales of these interactions. We use the XMM-Newton X-ray observations of NGC 3627 in the Leo Triplet galaxy group to explain peculiar features visible in the polarized radio maps. We analyzed soft X-ray (0.2-1 keV) emission from NGC 3627 to study the distribution of the hot gas and its temperature in different areas of the galaxy. Any change throughout the disk can reflect distortions visible in the radio polarized emission. We also studied two bright point sources that are probably tightly linked to the evolution of the galaxy. We find an increase in the temperature of the hot gas in the area of the polarized radio ridge in the western arm of the galaxy. In the eastern part of the disk we find two ultra-luminous X-ray sources. We note a large hot gas temperature difference (by a factor of 2) between the two bar ends. The polarized radio ridge in the western arm of NGC 3627 is most likely formed by ram-pressure effects caused by the movement of the galaxy through the intragroup medium. To explain the distortions visible in the eastern part of the disk in polarized radio maps, the asymmetry of the bar, and the distortion of the eastern arm, we propose a recent collision of NGC 3627 with a dwarf companion galaxy.

8 pages, 6 figures, 5 tables. Accepted for publication in Astronomy and Astrophysics

References in corpus (5)

• An H-alpha Imaging Survey of Galaxies in the Local 11 Mpc Volume
• The first XMM-Newton slew survey catalogue: XMMSL1
• The XMM-Newton EPIC Background and the production of Background Blank Sky Event Files
• Determining the Absolute Astrometric Error in Chandra Source Catalog Positions
• Correlation of the radio continuum, infrared, and CO molecular emissions in NGC 3627

Cited by in corpus (10)

• Dense molecular gas properties on 100 pc scales across the disc of NGC 3627
• Role of magnetic fields in fueling Seyfert nuclei
• Multi-Phase Magnetic Fields in the Galaxy NGC 3627
• SMA Observations of Extended $\mathrm{CO}(\mathrm{J}=2-1)$ Emission in Interacting Galaxy NGC 3627
• Discovery of a tidal dwarf galaxy in the Leo Triplet
• Radio continuum observations of the Leo Triplet at 2.64 GHz
• HI mapping of the Leo Triplet: Morphologies and kinematics of tails and bridges
• Relating spatially resolved optical attenuation, dust and gas in nearby galaxies
• A Lack of Evidence for Global Ram-pressure Induced Star Formation in the Merging Cluster Abell 3266
• Searching for the magnetised Tidal Dwarf Galaxies in Hickson Compact Groups: HCG 26, 91, and 96