Morphology and kinematics of the ionised gas in early-type galaxies

Abstract

We present results of our ongoing study of the morphology and kinematics of the ionised gas in 48 representative nearby elliptical and lenticular galaxies using the SAURON integral-field spectrograph on the 4.2m William Herschel Telescope. Making use of a recently developed technique, emission is detected in 75% of the galaxies. The ionised-gas distributions display varied morphologies, ranging from regular gas disks to filamentary structures. Additionally, the emission-line kinematic maps show, in general, regular motions with smooth variations in kinematic position angle. In most of the galaxies, the ionised-gas kinematics is decoupled from the stellar counterpart, but only some of them present signatures of recent accretion of gaseous material. The presence of dust is very common in our sample and is usually accompanied by gas emission. Our analysis of the [OIII]/Hbeta emission-line ratios, both across the whole sample as well as within the individual galaxies, suggests that there is no unique mechanism triggering the ionisation of the gas.

8 pages, 2 figures, submitted to "Adaptive Optics-Assisted Integral-Field Spectroscopy", Rutten R.G.M., Benn C.R., Mendez J., eds., May 2005, La Palma (Spain), New Astr. Rev. For full resolution PS, see http://www.strw.leidenuniv.nl/~jfalcon/JFB_AOmeeting_color_hires.ps.gz

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Cited by in corpus (10)

• The Spitzer Survey of Stellar Structure in Galaxies (S^4G)
• Nearby early-type galaxies with ionized gas. III. Analysis of line-strength indices with new stellar population models
• The SAURON project - XI. Stellar Populations from Absorption Line Strength Maps of 24 Early-Type Spirals
• The HI content of early-type galaxies from the ALFALFA survey. II. The case of low density environments
• Pattern Speeds of Bars and Spiral Arms From H-alpha Velocity Fields
• The cosmic assembly of stellar haloes in massive Early-Type Galaxies
• SINFONI/VLT 3D spectroscopy of massive galaxies: Evidence of rotational support at z~1.4
• Unexplored outflows in nearby low luminosity AGNs: the case of NGC 1052
• On the origin and fate of ionised-gas in early-type galaxies: the SAURON perspective
• Small Scale Systems of Galaxies. III. X-ray detected E+S galaxy pairs in low density environments