Morphological parameters of a Spitzer survey of stellar structure in galaxies

The morphology of galaxies can be quantified to some degree using a set of scale-invariant parameters. Concentration (C), asymmetry (A), smoothness (S), the Gini index (G), the relative contribution of the brightest pixels to the second-order moment of the flux (M_20), ellipticity (E), and the Gini...

Descripción completa

Detalles Bibliográficos
Autores: Holwerda, Benne W., Muñoz Mateos, Juan Carlos, Comerón, Sébastien, Meidt, Sharon E., Sheth, Kartik, Laine, S., Hinz, Joannah L., Regan, Michael W., Gil De Paz, Armando, Menéndez-Delmestre, Karín, Seibert, Mark, Kim, Taehyun, Mizusawa, Trisha, Laurikainen, Eija, Salo, Heikki, Laine, Jarkko, Gadotti, Dimitri A., Zaritsky, Dennis, Erroz Ferrer, Santiago, Ho, Luis C., Knapen, Johan H., Athanassoula, E., Bosma, Albert, Pirzkal, N.
Tipo de recurso: artículo
Fecha de publicación:2014
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/35011
Acceso en línea:https://hdl.handle.net/20.500.14352/35011
Access Level:acceso abierto
Palabra clave:52
H I Morphology
Digital-sky-survey
Polycyclic aromatic-hydrocarbons
High-redshift galaxies
Major merger fraction
Edge-on galaxies
Spiral galaxies
Seeing galaxies
Space-telescope
Nearby galaxies
Astrofísica
Astronomía (Física)
Descripción
Sumario:The morphology of galaxies can be quantified to some degree using a set of scale-invariant parameters. Concentration (C), asymmetry (A), smoothness (S), the Gini index (G), the relative contribution of the brightest pixels to the second-order moment of the flux (M_20), ellipticity (E), and the Gini index of the second-order moment (G_M ) have all been applied to morphologically classify galaxies at various wavelengths. Here, we present a catalog of these parameters for the Spitzer Survey of stellar structure in Galaxies, a volume-limited, near-infrared (NIR) imaging survey of nearby galaxies using the 3.6 and 4.5 μm channels of the Infrared Array Camera on board the Spitzer Space Telescope. Our goal is to provide a reference catalog of NIR quantified morphology for high-redshift studies and galaxy evolution models with enough detail to resolve stellar mass morphology. We explore where normal, non-interacting galaxies—those typically found on the Hubble tuning fork—lie in this parameter space and show that there is a tight relation between concentration (C_82) and M_20 for normal galaxies. M_20 can be used to classify galaxies into earlier and later types (i.e., to separate spirals from irregulars). Several criteria using these parameters exist to select systems with a disturbed morphology, i.e., those that appear to be undergoing a tidal interaction. We examine the applicability of these criteria to Spitzer NIR imaging. We find that four relations, based on the parameters A and S, G and M_20, G_M, C, and M_20, respectively, select outliers in morphological parameter space, but each selects different subsets of galaxies. Two criteria (G_M > 0.6, G > –0.115 × M_20 + 0.384) seem most appropriate to identify possible mergers and the merger fraction in NIR surveys. We find no strong relation between lopsidedness and most of these morphological parameters, except for a weak dependence of lopsidedness on concentration and M_20.

Similares en LA Referencia