We present results of deep integral-field spectroscopy observations using high-resolution optical (4150–7200 Å) VLT VIsible MultiObject Spectrograph spectra of NGC 4696, the dominant galaxy in the Centaurus cluster (Abell 3526). After the Virgo cluster, this is the second nearest (z= 0.0104) example of a cool-core cluster. NGC 4696 is surrounded by a vast, luminous Hα emission-line nebula (L= 2.2 × 1040 erg s−1). We explore the origin and excitation of the emission-line filaments and find their origin consistent with being drawn out, under rising radio bubbles, into the intracluster medium as in other similar systems. Contrary to previous observations, we do not observe evidence for shock excitation of the outer filaments. Our optical spectra are consistent with the recent particle heating excitation mechanism of Ferland et al.

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Published in Monthly Notices of the Royal Astronomical Society, v. 417, issue 4, p. 3080-3099.

This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society ©: 2011 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.

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