Open AccessEncounters between spherical galaxies – I. Systems without a dark halo
Author(s) -
GonzálezGarcía A. C.,
Van Albada T. S.
Publication year - 2005
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1111/j.1365-2966.2005.09242.x
Subject(s) - physics , oblate spheroid , prolate spheroid , astrophysics , galaxy , elliptical galaxy , halo , isotropy , astronomy , classical mechanics , optics
We report here on a survey of N ‐body simulations of encounters between spherical galaxies. Initial systems are isotropic Jaffe models. Different sets of mass ratios, impact parameters and orbital energies are studied. Both merger remnants and systems perturbed after a non‐merging encounter are analysed and compared to real‐life elliptical galaxies. The properties of merger remnants show a large variety. Merger remnants resulting from head‐on encounters are mainly non‐rotating prolate spheroids. Merger remnants from models with J orb ≠ 0 are tri‐axial or mildly oblate spheroids, supported in part by rotation. The velocity distributions are biased towards the radial direction in the prolate case and the tangential direction in the oblate case. Non‐mergers are affected in various ways, depending on the orbital characteristics. We conclude that many of the global properties of real‐life ellipticals can, in principle, be attributed to a merger of spherical progenitors.