Tidal Stripping and Intracluster Light

(CWRU team: Feldmeier, Mihos, Morrison, Harding, Rodney, Kaib, McBride)

In clusters, tidal debris mixes over time to form a diffuse "intracluster light" (Zwicky 1951).

The properties of this intracluster light -- the amount, radial profile, and spatial distribution -- may hold clues to the accretion history of clusters.

Earlier theoretical studies argued that anywhere from 10-70% of the starlight in a cluster could be found in this intracluster light (eg Merritt 1983; Richstone & Malamuth 1983). Now, high resolution simulations can be used to study the phenomenon in a cosmological context (Moore etal 1998, Dubinski etal 2000).

Calcaneo-Roldan etal 2000: Centaurus

Gregg & West 1998: Coma

Modelling the ICL (Feldmeier etal 2003):

Early Stages of Cluster Collapse (z~2)

Late Time Morphology (z=0)

Quantifying the ICL in clusters (Feldmeier etal 2002, 2003)

KPNO 2.1m + T2KA CCD (coming soon: CWRU Burrell Schmidt for nearby clusters and groups!)
Washington M
Flat field using "super sky flats" (Morrison etal 1994, 1997)
Aggressive masking to eliminate stellar wings and background sources
Limits: S/N=5 @ mu(V)=26.5, S/N=1 @ mu(V)=28.3
Early Results - cD envelopes and ICL substructure

cD-dominated (BM1) clusters (Feldmeier etal 2002):

Abell 1413 slight excess of light at large radius, no significant substructure (see also Gonzalez poster).
MKW 7 again, slight excess of light at large radius, also broad, diffuse plume seen.

Bautz-Morgan III clusters (Feldmeier etal 2003)

Abell 1234

Abell 1914

The Not-too-distant future: ICL kinematics

tracers: intracluster PNe (eg Feldmeier etal 1998; Arnaboldi etal)

similar in concept to studies of substructure in the galactic halo (eg Harding etal 2001; Morrison etal 2001).

(from Dubinski unpublished; see also Willman thesis)