Analysis and measurement of storage ring Robinson instability

The Robinson instability of storage ring is discussed. A new beam stability condition that the equivalent detuning angle should be over zero is presented. The relationship between the beam instability and the detuning of RF cavity is measured during 200 MeV injection at Hefei Light Source storage ring. The results indicate that when the beam stability condition is not satisfied, the beam will be lost if the detuning is large; the beam tends to be lost partially when the detuning is small; in the case of negative detuning, the beam current is limited within a low level.