The effect of CSR can also be described in terms of wake
fields [18]. It takes place in a magnetic bend when the
radiation from the tail of the bunch catches up with its head.
For a beam of high-current and short bunch length, this effect
may become important. Electromagnetic shielding near the
beam axis, in particular if the bunch length is long enough
may mitigate CSR. The suppression factor involves the bunch
length, the beam pipe diameter, and the bending radius of the
curvature of the beam in the magnet. Dedicated measurements
of shielding of the CSR were performed at the BNL Accelerator
Test Facility, where both CSR-induced energy loss and
energy spread were suppressed [19].