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We use new high-resolution HI data from the Australian Square Kilometre Array Pathfinder (ASKAP) to investigate the dynamics of the Small Magellanic Cloud (SMC). We model the HI gas component as a rotating disc of non-negligible angular size, moving into the plane of the sky and undergoing nutation/precession motions. We derive a high-resolution (~ 10 pc) rotation curve of the SMC out to R ~ 4 kpc. After correcting for asymmetric drift, the circular velocity slowly rises to a maximum value of Vc ~ 55 km/s at R ~ 2.8 kpc and possibly flattens outwards. In spite of the SMC undergoing strong gravitational interactions with its neighbours, its HI rotation curve is akin to that of many isolated gas-rich dwarf galaxies. We decompose the rotation curve and explore different dynamical models to deal with the unknown three-dimensional shape of the mass components (gas, stars and dark matter). We find that, for reasonable mass-to-light ratios, a dominant dark matter halo with mass M(R<4 kpc) = 1-1.5 x 10^9 solar masses is always required to successfully reproduce the observed rotation curve, implying a large baryon fraction of 30%-40%. We discuss the impact of our assumptions and the limitations of deriving the SMC kinematics and dynamics from HI observations.
Feedback from massive stars plays a critical role in the evolution of the Universe by driving powerful outflows from galaxies that enrich the intergalactic medium and regulate star formation. An important source of outflows may be the most numerous g
We present two new radio continuum images from the Australian Square Kilometre Array Pathfinder (ASKAP) survey in the direction of the Small Magellanic Cloud (SMC). These images are part of the Evolutionary Map of the Universe (EMU) Early Science Pro
We present the first results from the Small Magellanic Cloud portion of a new Australia Telescope Compact Array (ATCA) HI absorption survey of both of the Magellanic Clouds, comprising over 800 hours of observations. Our new HI absorption line data a
The first INTEGRAL observations of the Small Magellanic Cloud (carried out in 2003) are reported in which two sources are clearly detected. The first source, SMC X-1, shows a hard X-ray eclipse and measurements of its pulse period indicate a continua
The last comprehensive catalogue of high-mass X-ray binaries in the Small Magellanic Cloud (SMC) was published about ten years ago. Since then new such systems were discovered, mainly by X-ray observations with Chandra and XMM-Newton. For the majorit