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Freitas-Lemes P.,University of Paraiba Valley | Rodrigues I.,University of Paraiba Valley | Dors Jr. O.L.,University of Paraiba Valley | Faundez-Abans M.,Mct Laboratorio Nacional Of Astrofisica | Perez-Montero E.,Institute Astrofisica Of Andalucia Csic
Monthly Notices of the Royal Astronomical Society | Year: 2014

This observational study is about the effects of interaction on the kinematics and chemical abundance of the component galaxies of AM 2229-735. This system is formed by a disc galaxy, NED01, and a compact perturbed Sb(s)-like galaxy, NED02, the latter showing a tail and counter-tail arc-shaped feature. This system could be a progenitor of a polar ring galaxy. The sky-projected tail is very luminous and seems to connect the galaxies. Our study was based on BVRI broad-band imagery as well as long-slit spectroscopy in the wavelength range 4240-8700 Å. We estimated heliocentric radial velocities of 17 518 ± 25 km s-1 (NED01) and 17 326 ± 27 km s-1 (NED02). Standard diagnostic diagrams were used to classify the main ionizing source of selected emission-line regions. It turns out that all regions are mainly ionized by massive stars. Using two empirical methods, we found that the H II regions in AM 2229-735 have high metallicity: 12 + log(O/H) = 8.3-8.6 dex. © 2014 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society.

da Rocha-Poppe P.C.,Novo A/S | Faundez-Abans M.,Mct Laboratorio Nacional Of Astrofisica | Fernandes-Martin V.A.,Novo A/S | Fernandes I.F.,Mct Laboratorio Nacional Of Astrofisica | And 2 more authors.
Monthly Notices of the Royal Astronomical Society | Year: 2010

We present the first spectroscopic observations for the galaxies ESO 089-G018 (hereafter G18, an Sb(?)-type galaxy seen nearly edge-on) and ESO 089-G019 (hereafter G19, an SA(s): a peculiar galaxy), extracted from the sample of ring-shaped galaxies compiled in Faúndez-Abans & de Oliveira-Abans. The main goal of this work is to investigate the spectral classification using the three line-ratio diagrams, called diagnostic diagrams, of Veilleux & Osterbrock. However, in order to separate the different types of galaxies [H ii galaxies, Seyfert 2 galaxies and low-ionization nuclear emission-line region galaxies (LINERs)] we have to used empirical boundaries between them. Based on the observed spectra, we suggest G18 is a 'weak-[O i] LINER' or even a 'transition object' or LINER/H ii. In the case of G19, we see Hβ in absorption and no [O iii] lines, impeding the [O iii]/Hβ ratio to be estimated. However, other lines ratios have been evaluated for the discussion. We classify the nature of G19 as ambiguous, because of the difficulty in determining its ionizing source (narrow-line active galactic nuclei or H ii galaxies) in different diagnostic diagrams. The errors in the fluxes were mostly caused by uncertainties in the placement of the continuum level. We have estimated nuclear redshift of z = 0.034 (G18) and z = 0.039 (G19), corresponding to a heliocentric velocity of 10 246 and 11 734 km s-1, respectively. Some other physical parameters have been derived whenever possible. All spectra were reduced and analysed in a homogeneous way with the standard iraf procedures. © 2009 The Authors. Journal compilation © 2009 RAS.

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