Ring galaxies in the EAGLE hydrodynamical simulations

Authors
Elagali, Ahmed; Lagos Urbina, Claudia del Pilar; IvyWong, O.; Staveley-Smith, Lister; Trayford, James W.; Schaller, Matthieu; Yuan, Tiantian; Abadi, Mario Gabriel
Publication Year
2018
Language
English
Format
article
Status
Published version
Description
We study the formation and evolution of ring galaxies in the Evolution and Assembly of GaLaxies and their Environments (EAGLE) simulations. We use the largest reference model Ref-L100N1504, a cubic cosmological volume of 100 cMpc on a side, to identify and characterize these systems through cosmic time. The number density of ring galaxies in EAGLE is in broad agreement with the observations. The vast majority of ring galaxies identified in EAGLE (83 per cent) have an interaction origin, i.e. form when one or more companion galaxies drop-through a disc galaxy. The remainder (17 per cent) have very long-lived ring morphologies (> 2Gyr) and host strong bars. Ring galaxies are HI-rich galaxies, yet display inefficient star formation activity and tend to reside in the green valley particularly at z ≳ 0.5. This inefficiency is mainly due to the low pressure and metallicity of their interstellar medium (ISM) compared with the ISM of similar star-forming galaxies.We find that the interaction(s) is responsible for decreasing the ISM pressure by causing the ISM gas to flow from the inner regions to the outer disc, where the ring feature forms. At a fixed radius, the star formation efficiency of ring galaxies is indistinguishable from their star-forming counterparts, and thus themain reason for their integrated lower efficiency is the different gas surface density profiles. Since galaxy morphologies are not used to tune the parameters in hydrodynamical simulations, the experiment performed here demonstrates the success of the current numerical models in EAGLE.
Fil: Elagali, Ahmed. University of Western Australia; Australia. Arc Centre Of Excellence For All Sky Astrophysics In 3 Dimensions (astro 3d); Australia
Fil: Lagos Urbina, Claudia del Pilar. University of Western Australia; Australia. Arc Centre Of Excellence For All Sky Astrophysics In 3 Dimensions (astro 3d); Australia
Fil: IvyWong, O.. Arc Centre Of Excellence For All Sky Astrophysics In 3 Dimensions (astro 3d); Australia. University of Western Australia; Australia
Fil: Staveley-Smith, Lister. University of Western Australia; Australia. Arc Centre Of Excellence For All Sky Astrophysics In 3 Dimensions (astro 3d); Australia
Fil: Trayford, James W.. University of Durham; Reino Unido. Leiden Observatory Research Institute; Países Bajos
Fil: Schaller, Matthieu. Leiden Observatory Research Institute; Países Bajos. University of Durham; Reino Unido
Fil: Yuan, Tiantian. Swinburne University Of Technology; Australia. Arc Centre Of Excellence For All Sky Astrophysics In 3 Dimensions (astro 3d); Australia
Fil: Abadi, Mario Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Astronomía Teórica y Experimental. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Instituto de Astronomía Teórica y Experimental; Argentina
Subject
COSMOLOGY: THEORY
GALAXIES: FORMATION
GALAXIES: HALOES
GALAXIES: STATISTICS
GALAXIES: STRUCTURE
METHODS: NUMERICAL
Otras Ciencias Naturales y Exactas
Otras Ciencias Naturales y Exactas
CIENCIAS NATURALES Y EXACTAS
Access level
Open access
License
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
Repository
CONICET Digital (CONICET)
Institution
Consejo Nacional de Investigaciones Científicas y Técnicas
OAI Identifier
oai:ri.conicet.gov.ar:11336/87047