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arXiv · astro-ph/0209108

Kinematics of Planetary Nebulae in M51's Tidal Debris

Abstract

We report the results of a radial velocity survey of planetary nebulae (PNe) located in the tidal features of the well-known interacting system NGC 5194/95 (M51). We find clear kinematic evidence that M51's northwestern tidal debris consists of two discrete structures which overlap in projection -- NGC 5195's own tidal tail, and diffuse material stripped from NGC 5194. We compare these kinematic data to a new numerical simulation of the M51 system, and show that the data are consistent with the classic ``single passage'' model for the encounter, with a parabolic satellite trajectory and a 2:1 mass ratio. We also comment on the spectra of two unusual objects: a high-velocity PN which may be associated with NGC 5194's halo, and a possible interloping high-redshift galaxy.

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Patrick R. Durrell, J. Christopher Mihos, John J. Feldmeier, George H. Jacoby, Robin Ciardullo. 2002-09-05. Kinematics of Planetary Nebulae in M51's Tidal Debris. https://doi.org/10.1086/344612

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