The haloes and environments of nearby galaxies (HERON) - II. The outer structure of edge-on galaxies

The HERON project is aimed at studying haloes and low surface brightness details near galaxies. In this second HERON paper we consider in detail deep imaging (down to surface brightness of ∼28 mag/arcsec<SUP>2</SUP> in the r band) for 35 galaxies, viewed edge-on. We confirm a range of lo...

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Detalles Bibliográficos
Autores: Mosenkov, Aleksandr, Rich, R. Michael, Koch, Andreas, Brosch, Noah, Thilker, David, Román, Javier, Müller, Oliver, Smirnov, Anton, Usachev, Pavel
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2020
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/211500
Acceso en línea:http://hdl.handle.net/10261/211500
Access Level:acceso abierto
Palabra clave:Galaxies: evolution
Galaxies: formation
Galaxies: haloes
Galaxies: interactions
Galaxies: photometry
Galaxies: structure
Descripción
Sumario:The HERON project is aimed at studying haloes and low surface brightness details near galaxies. In this second HERON paper we consider in detail deep imaging (down to surface brightness of ∼28 mag/arcsec<SUP>2</SUP> in the r band) for 35 galaxies, viewed edge-on. We confirm a range of low surface brightness features previously described in the literature but also report new ones. We classify the observed outer shapes of the galaxies into three main types (and their prototypes): disc/diamond-like (NGC 891), oval (NGC 4302), and boxy (NGC 3628). We show that the shape of the outer disc in galaxies does not often follow the general 3D model of an exponential disc: 17 galaxies in our sample exhibit oval or even boxy isophotes at the periphery. Also, we show that the less flattened the outer disc is, the more oval or boxy its structure. Many galaxies in our sample have an asymmetric outer structure. We propose that the observed diversity of the galaxy outer shapes is defined by the merger history and its intensity: if no recent multiple minor or single major merging took place, the outer shape is diamond-like or discy. On the contrary, interacting galaxies show oval outer shapes, whereas recent merging appears to transform the outer shape to boxy.© 2020 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society