The multi-bend achromat storage rings
Not very long ago, the 3rd generation storage ring technology was judged as mature. Most of the 3rd generation storage rings used the Double-Bend Achromat (DBA) or Triple-Bend Achromat (TBA) concepts. It was however a well-known fact that increasing the number of magnet cells in the rings is a powerful way of decreasing the electron beam emittance and thus the source brilliance, but at the penalty