Optical IFU Observations of the Brightest Cluster Galaxy NGC 4696: The Case for a Minor Merger and Shock-excited Filaments
Abstract
We present deep optical integral-field spectroscopic observations of the nearby (z ~ 0.01) brightest cluster galaxy NGC 4696 in the core of the Centaurus Cluster, made with the Wide Field Spectrograph on the Australian National University 2.3 m telescope at Siding Spring Observatory. We investigate the morphology, kinematics, and excitation of the emission-line filaments and discuss these in the context of a model of a minor merger. We suggest that the emission-line filaments in this object have their origin in the accretion of a gas-rich galaxy and that they are excited by v ~ 100-200 km s-1 shocks driven into the cool filament gas by the ram pressure of the transonic passage of the merging system through the hot halo gas of NGC 4696.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- November 2010
- DOI:
- 10.1088/0004-637X/724/1/267
- arXiv:
- arXiv:1009.3070
- Bibcode:
- 2010ApJ...724..267F
- Keywords:
-
- galaxies: elliptical and lenticular;
- cD;
- galaxies: individual: NGC 4696;
- galaxies: interactions;
- galaxies: ISM;
- shock waves;
- techniques: imaging spectroscopy;
- Astrophysics - Cosmology and Extragalactic Astrophysics
- E-Print:
- 19 pages, 15 figures, accepted for publication in The Astrophysical Journal