The Magellanic impact: Collision between the outer Galactic HI disk and the leading arms of the Magellanic stream

Abstract

We show that collisions between the outer Galactic HI disk and the leading arms (LAs) of the Magellanic stream (MS) can create giant HI holes and chimney-like structures in the disk. Based on the results of our N-body simulations on the last 2.5 Gyr evolution of the Large and Small Magellanic Clouds (LMC and SMC, respectively) interacting with the Galaxy, we investigate when and where the LAs can pass through the Galactic plane after the MS formation. We then investigate hydrodynamical interaction between LAs and the Galactic HI disk (``the Magellanic impact'') by using our new hydrodynamical simulations with somewhat idealized models of the LAs. We find that about 1-3% of the initial gas mass of the SMC, which consists of the LAs, can pass through the outer part (R=20-35 kpc) of the Galactic HI disk about 0.2 Gyr ago. We also find that the Magellanic impact can push out some fraction (~1%) of the outer Galactic HI disk to form 1-10 kpc-scale HI holes and chimney-like bridges between the LAs and the disk.

13pages, 4 figures, accepted by ApJL

References in corpus (18)

• N-body Simulations of the Small Magellanic Cloud and the Magellanic Stream
• Is the SMC Bound to the LMC? The HST Proper Motion of the SMC
• The disruption of nearby galaxies by the Milky Way
• The Parkes HI Survey of the Magellanic System
• The Spiral Structure of the Outer Milky Way in Hydrogen
• The gravitational and hydrodynamical interaction between the LMC and the Galaxy
• Spectroscopic Survey of Red Giants in the SMC. I: Kinematics
• Formation and evolution of the Magellanic Clouds. I.Origin of structural, kinematical, and chemical properties of the Large Magellanic Cloud
• N-body simulations of the Magellanic Stream
• AGB stars in the Magellanic Clouds. II. The rate of star formation across the LMC
• A Magellanic Origin for the Warp of the Galaxy
• A Distant Extended Spiral Arm in the Fourth Quadrant of the Milky Way
• The Magellanic Squall: Gas Replenishment from the Small to Large Magellanic Cloud
• Evidence for chimney breakout in the Galactic supershell GSH 242-03+37
• Young Stars in the Outer HI Disc of NGC 6822
• Impact of dark matter subhalos on extended HI disks of galaxies: Possible formation of HI fine structures and stars
• Contribution of the Large Magellanic Cloud to the Galactic Warp
• The Origin of Large-scale HI structures in the Magellanic Bridge

Cited by in corpus (4)

• Formation of a giant HI bridge between M31 and M33 from their tidal interaction
• Origin of structural and kinematical properties of the Small Magellanic Cloud
• Discovery of a disrupting open cluster far into the Milky Way halo: a recent star formation event in the leading arm of the Magellanic stream?
• The Effect of Drag from the Galactic Hot Halo on the Magellanic Stream and Leading Arm