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arXiv · 1206.0719

A study of the remarkable galaxy system AM 546-324 (the core of Abell S0546)

M. Faúndez-Abans·A. C. Krabbe·M. Oliveira-Abans·P. C. da Rocha Poppe·I. Rodrigues·V. A. Fernandes Martin·I. F. Fernandes
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Abstract

We report first results of an investigation of the tidally disturbed galaxy system AM\,546-324, whose two principal galaxies 2MFGC 04711 and AM\,0546-324 (NED02) were previously classified as interacting doubles. This system was selected to study the interaction of ellipticals in a moderately dense environment. We provide spectral characteristics of the system and present an observational study of the interaction effects on the morphology, kinematics, and stellar population of these galaxies. The study is based on long-slit spectrophotometric data in the range of $\sim$ 4500-8000 $\AA$ obtained with the Gemini Multi-Object Spetrograph at Gemini South (GMOS-S). We have used the stellar population synthesis code STARLIGHT to investigate the star formation history of these galaxies. The Gemini/GMOS-S direct r-G0303 broad band pointing image was used to enhance and study fine morphological structures. The main absorption lines in the spectra were used to determine the radial velocity. Along the whole long-slit signal, the spectra of the Shadowy galaxy (discovered by us), 2MFGC 04711, and AM\,0546-324 (NED02) resemble that of an early-type galaxy. We estimated redshifts of z= 0.0696, z= 0.0693 and z= 0.0718, corresponding to heliocentric velocities of 20\,141 km s$^{-1}$, 20\,057 km s$^{-1}$, and 20\,754 km s$^{-1}$ for the Shadowy galaxy, 2MFGC 04711 and AM\,0546-324 (NED02), respectively. ...

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M. Faúndez-Abans, A. C. Krabbe, M. Oliveira-Abans, P. C. da Rocha Poppe, I. Rodrigues, V. A. Fernandes Martin, I. F. Fernandes. 2012-06-04. A study of the remarkable galaxy system AM 546-324 (the core of Abell S0546). https://doi.org/10.1051/0004-6361/201219061

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