A Wide-Field Spectroscopic Survey In The Cluster Lens Cl0024+17

We present a detailed velocity histogram from a wide-field spectroscopic survey in the field of the cluster lens Cl0024 showing an unrelaxed foreground structure in addition to the relaxed main cluster. This finding reduces the velocity dispersion of the main cluster compared to previous studies by a factor of about 2 and thus resolves the discrepancy between previous mass estimates for this cluster.