Outer halos of early-type galaxies and intracluster light
Galaxies in a hierarchical universe are growing through accreting smaller systems. We study particularly the outer halos of massive galaxies to find signatures of this process, but also to characterize the kinematics, angular momentum, and dark matter in these halos, and to determine how they blend into their surroundings, the intracluster or intragroup light. We also host the website of the Planetary Nebula Spectrograph (PN.S) project; planetary nebulae are some of the best tracers to study the outermost regions of galaxies which are too faint for conventional spectroscopy.
Longobardi, A., Arnaboldi, M., Gerhard, O., Mihos, J. C., 2015, A&A, 579, L3,
The build-up of the cD halo of M 87: evidence for accretion in the last Gyr. 2015A&A...579L...3L
Longobardi, A., Arnaboldi, M., Gerhard, O., Hanuschik, R., 2015, A&A, 579, A135,
The outer regions of the giant Virgo galaxy M 87 Kinematic separation of stellar halo and intracluster light. 2015A&A...579A.135L
Morganti, L., Gerhard, O., Coccato, L., Martinez-Valpuesta, I., Arnaboldi, M., 2013, MNRAS, 431, 3570,
Elliptical galaxies with rapidly decreasing velocity dispersion profiles: NMAGIC models and dark halo parameter estimates for NGC 4494.
Coccato, L., Gerhard, O., Arnaboldi, M., Das, P., Douglas, N. G., Kuijken, K., et al., 2009, MNRAS, 394, 1249,
Kinematic properties of early-type galaxy haloes using planetary nebulae. 2009MNRAS.394.1249C
de Lorenzi, F., Gerhard, O., Saglia, R. P., Sambhus, N., Debattista, V. P., Pannella, M., et al., 2008, MNRAS, 385, 1729,
Dark matter content and internal dynamics of NGC 4697: NMAGIC particle models from slit data and planetary nebula velocities. 2008MNRAS.385.1729D