Elliptical galaxies from mergers of discs

[EN]We analyse N-body galaxy merger experiments involving disc galaxies. Mergers of disc–bulge–halo models are compared to those of bulgeless, disc–halo models to quantify the effects of the central bulge on merger dynamics and the structure of the remnant. Our models explore galaxy mass ratios 1:1...

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Detalles Bibliográficos
Autores: González-García, A. César, Balcells, Marc
Tipo de recurso: artículo
Fecha de publicación:2005
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/75051
Acceso en línea:http://hdl.handle.net/10261/75051
Access Level:acceso abierto
Palabra clave:Galaxies: elliptical and lenticular, cD
Galaxies: interactions
Galaxies: kinematics and dynamics
Galaxies: structure
Incipit
Institute of Heritage Sciences
Instituto de Ciencias del Patrimonio
Descripción
Sumario:[EN]We analyse N-body galaxy merger experiments involving disc galaxies. Mergers of disc–bulge–halo models are compared to those of bulgeless, disc–halo models to quantify the effects of the central bulge on merger dynamics and the structure of the remnant. Our models explore galaxy mass ratios 1:1 through 3:1, and use higher bulge mass fractions than previous studies. A full comparison of the structural and dynamical properties with our observations is carried out. The presence of central bulges results in longer tidal tails, oblate final intrinsic shapes, surface brightness profiles with a higher Sérsic index, steeper rotation curves and oblate-rotator internal dynamics. Mergers of bulgeless galaxies do not generate long-lasting tidal tails, and their strong triaxiality seems inconsistent with observations; these remnants show shells, which we do not find in models including central bulges. Giant ellipticals with boxy isophotes and anisotropic dynamics cannot be produced by the mergers modelled here; they could be the result of mergers between lower luminosity ellipticals, themselves plausibly formed in disc-disc mergers.