The Sources of Ionisation for the Gas of Early-type Galaxies, the SAURON Answer
Marc SARZI
University of Hertfordshire
Résumé :
The SAURON survey has revealed that down to a detection limit of
0.1\AA. ~~~ 75 \% of early-type galaxies display diffuse ionised-gas emission,
which comes with an intriguing variety of spatial distributions,
kinematic behaviours, and emission-line ratios. I will investigate the
relative role of AGN activity, star-formation, shocks, thermal
conduction and photo-ionisation by evolved stars in powering the
observed nebular emission of early-type galaxies. Drawing on
these results I will suggest that caution is needed when studying the
unresolved nebular emission observed in early-type galaxies
through large-scale surveys such as the SDSS survey, in particular when
it comes to interpreting AGN activity.
