The scattered debris of the Magellanic Stream

TL;DR

This paper reports the discovery of compact high-velocity clouds aligned with the Magellanic Stream, suggesting the stream is more extensive and contains condensations within an ionised gas component.

Contribution

It provides observational evidence linking compact HVCs to the Magellanic Stream, indicating a larger and more complex structure than previously thought.

Findings

HVCs are aligned with the Magellanic Stream.

HVCs are likely condensations within an ionised component.

The Magellanic Stream may be more extended than previously believed.

Abstract

Searching the HI Parkes All-Sky Survey (HIPASS) and its northern extension, we detected a population of very compact high-velocity clouds (HVCs) with similar velocities in the Galactic standard-of-rest frame which appear to be arranged in several filaments aligned with the nearby Magellanic Stream. A comparison with published OVI/CaII absorption and HI emission line measurements suggests that the HVCs are condensations within an extended and mainly ionised component of the Magellanic Stream. They coincide in position with a faint gas stream predicted in numerical simulations of the Magellanic Clouds by Gardiner & Noguchi (1996). Consequently, the Magellanic Stream could be much more extended than generally believed.