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arXiv · astro-ph/0301056

Possibly interacting Vorontsov-Velyaminov galaxies. II. The 6m telescope spectroscopy of VV 080, 131, 499, 523 and 531

Abstract

In continuation of the program formulated in Paper I we present results of long-slit spectroscopy with the Russian 6m telescope of five more objects from the Vorontsov-Velyaminov Atlas and Catalogue of Interacting galaxies. These are the galaxies for which the interaction is not evident, although all of them are classified as multiple systems (usually as ``nests'', ``chains'' and similar systems). The spectrophotometry data enable us to derive for all galaxies abundances of O, and for some of them abundances of N, Ne and S. For two of them chemical abundances are given for the first time. In spectra of three of the studied galaxies [Oiii]4363 line is measured, and T_e and oxygen abundance are derived by the classical method. For the two others, empirical methods are used. For all 5 galaxies, the radial velocity distribution along the slit was obtained in the Ha-line. The studied galaxies represent a rather mixed sample: from very low luminosity irregular galaxies, like VV 499 (DDO 053), to rather bright VV 523 (NGC 3991). Their metallicities vary from Z=1/25 Zo for VV 499 to 1/2 Zo for VV 523. The morphology of these galaxies ranges between typical dIrr (VV 080) through ring-like (VV 131) to clumpy Irr (VV 523). Position--Velocity diagrams in the Ha-line along the galaxy body imply the existence of large-scale ionized gas outflows/supershells around the sites of intense current and/or recent SF activity. Sizes of supershells vary in the range of several hundred pc to about 2 kpc. For all studied galaxies we examine their local environment and indicate the nearest neighbouring objects capable of inducing the observed enhanced star formation.

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BibTeXRIS

S. Pustilnik, A. Zasov, A. Kniazev, A. Pramskij, A. Ugryumov, A. Burenkov. 2003-01-05. Possibly interacting Vorontsov-Velyaminov galaxies. II. The 6m telescope spectroscopy of VV 080, 131, 499, 523 and 531. https://doi.org/10.1051/0004-6361%3A20021913

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