Is a minor merger driving the nuclear activity in the Seyfert 2 galaxy NGC 2110?

We report on a detailed morphological and kinematic study of the isolated nonbarred nearby Seyfert 2 galaxy NGC 2110. We combine integral field optical spectroscopy with long-slit and WFPC2 imaging available in the Hubble Space Telescope archive to investigate the fueling mechanism in this galaxy. P...

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Detalles Bibliográficos
Autores: González Delgado, Rosa M., Arribas-Mocoroa, Santiago, Pérez, Enrique, Heckman, T. M.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2002
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/199274
Acceso en línea:http://hdl.handle.net/10261/199274
Access Level:acceso abierto
Palabra clave:Galaxies: active
Galaxies: individual
Galaxies: kinematics and dynamics
Galaxies: nuclei
Galaxies: seyfert
Descripción
Sumario:We report on a detailed morphological and kinematic study of the isolated nonbarred nearby Seyfert 2 galaxy NGC 2110. We combine integral field optical spectroscopy with long-slit and WFPC2 imaging available in the Hubble Space Telescope archive to investigate the fueling mechanism in this galaxy. Previous work (Wilson & Baldwin) concluded that the kinematic center of the galaxy is displaced ∼220 pc from the apparent mass center of the galaxy, and the ionized gas follows a remarkably normal rotation curve. Our analysis, which is based on the stellar kinematics, two-dimensional ionized gas velocity field and dispersion velocity, and high spatial resolution morphology at V, I, and Hα, reveals the following: (1) The kinematic center of NGC 2110 is at the nucleus of the galaxy. (2) The ionized gas is not in pure rotational motion. (3) The morphology of the two-dimensional distribution of the emission-line widths suggests the presence of a minor axis galactic outflow. (4) The nucleus is blueshifted with respect to the stellar systemic velocity, suggesting the narrow-line region gas is outflowing owing to the interaction with the radio jet. (5) The ionized gas is redshifted ∼100 km s-1 over the corresponding rotational motion south of the nucleus and 240 km s-1 with respect to the nuclear stellar systemic velocity. This velocity is coincident with the H I redshifted absorption velocity detected by Gallimore et al. We discuss the possibility that the kinematics of the south ionized gas could be perturbed by a collision with a small satellite that impacted on NGC 2110 close to the center with a highly inclined orbit. Additional supports for this interpretation are the radial dust lanes and tidal debris detected in the V unsharp-masked image. We suggest that a minor merger may have driven the nuclear activity in NGC 2110.