Dynamics and Stellar Content of the Giant Southern Stream in M31. II. Interpretation

  title={Dynamics and Stellar Content of the Giant Southern Stream in M31. II. Interpretation},
  author={A. Font and K. Johnston and P. Guhathakurta and S. Majewski and R. Rich},
  journal={The Astronomical Journal},
We examine the nature of the progenitor of the giant stellar stream in M31 using as constraints new radial velocity measurements of stream red giant stars (presented in the companion paper by Guhathakurta and coworkers) along with other M31 data sets available in the literature. We find that the observations are best fitted by orbits that are highly eccentric and close to edge-on, with apocenter to pericenter ratios on the order of 25-30 and with apocenters at or only slightly beyond the… Expand

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