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Appendix A: Orbits in a non-axisymmetric Galactic model

We also ran the simulations in a non-axisymmetric galactic potential, in order to verify the bar effect in our results. The Galactic model that we considered is the analytical potential presented in Sect. 4, and the non-axisymmetric Galactic potential including a prolate bar given by Pichardo et al. (2004) to the galactic bar, with a total mass of ~1.6 × 10¹⁰M_⊙ and angular velocity of ω_B = 55 ± 5 km s^-1 kpc^-1 (e.g., Pichardo et al. 2012). Using the same considerations as in Sect. 4 to model the orbits of the RAVE stars and ω Centauri, 10⁵ pairs of orbits were integrated to 0.2 Gyr in the past. Figures A.1 and A.2 show the results to the stars listed in Table 1; the probabilities of close encounters are similar in both Galactic potential, and the bar effects for integration time <0.2 Gyr, do not affect the results presented in this work.

	Fig. A.1 Relative velocity (Vrel) distribution for 105 pairs of orbits integrated backward in time over 0.2 Gyr in an axisymmetric (pink histograms) and non-axisymmetric potential (black histograms).
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	Fig. A.2 davg distribution. The pink and red histograms are the same as in Fig. A.1.
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© ESO, 2015