Increase of the transverse strong head-tail stability threshold by an alternating chromaticity

It has been shown that the transverse head-tail instability can be suppressed by modulating the chromaticity over a synchrotron period. In this work, we demonstrate that the threshold of the strong head-tail instability can be significantly increased by the alternating chromaticity (AC). We present results of multi-particle simulation and a new criterion for the SHT instability.