Charting galactic accelerations: when and how to extract a unique potential from the distribution function

@article{An2021ChartingGA,
  title={Charting galactic accelerations: when and how to extract a unique potential from the distribution function},
  author={J. An and Aneesh P. Naik and N. W. Evans and Clare Burrage},
  journal={Monthly Notices of the Royal Astronomical Society},
  year={2021}
}
The advent of data sets of stars in the Milky Way with 6D phase-space information makes it possible to construct empirically the distribution function (DF). Here, we show that the accelerations can be uniquely determined from the DF using the collisionless Boltzmann equation, providing the Hessian determinant of the DF with respect to the velocities is non-vanishing. We illustrate this procedure and requirement with some analytic examples. Methods to extract the potential from data sets of… Expand

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