The need for speed: escape velocity and dynamical mass measurements of the Andromeda galaxy

  title={The need for speed: escape velocity and dynamical mass measurements of the Andromeda galaxy},
  author={Prajwal R. Kafle and Sanjib Sharma and Geraint F. Lewis and Aaron S. G. Robotham and Simon P. Driver},
  journal={Monthly Notices of the Royal Astronomical Society},
Our nearest large cosmological neighbour, the Andromeda galaxy (M31), is a dynamical system, and an accurate measurement of its total mass is central to our understanding of its assembly history, the life-cycles of its satellite galaxies, and its role in shaping the Local Group environment. Here, we apply a novel approach to determine the dynamical mass of M31 using high velocity Planetary Nebulae (PNe), establishing a hierarchical Bayesian model united with a scheme to capture potential… 

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