Abstract

Transverse mode coupling instability is one of the major limitations of a single bunch current in storage rings. Until now it has appeared in large electron-positron machines, while its presence in proton colliders has not been observed. This paper describes a theoretical analysis of the effect of longitudinal variation of the betatron tune on the transverse mode coupling instability. This variation can be introduced by an RF quadrupole. In the result, the instability threshold could be significantly increased when a modulation of the betatron frequency is comparable with the synchrotron tune.

Highlights

  • [1] it was discovered by simulations that an incoherent tune shift can increase the threshold current for the fast head-tail instability

  • A remarkable rise in the threshold current of transverse coupled-bunch instabilities was observed at the Photon Factory at KEK (Japan) using a high frequency quadrupole magnet [2]

  • The definitions of wake functions correspond to [4]; all of the results are obtained in general form

Read more

Summary

Increasing the transverse mode coupling instability threshold by RF quadrupole

Transverse mode coupling instability is one of the major limitations of a single bunch current in storage rings. Until now it has appeared in large electron-positron machines, while its presence in proton colliders has not been observed. This paper describes a theoretical analysis of the effect of longitudinal variation of the betatron tune on the transverse mode coupling instability. This variation can be introduced by an RF quadrupole. The instability threshold could be significantly increased when a modulation of the betatron frequency is comparable with the synchrotron tune. The instability threshold could be significantly increased when a modulation of the betatron frequency is comparable with the synchrotron tune. [S1098-4402(98)00012-3]

INTRODUCTION
Taking into account that
Mode coupling coefficients
Eigenfrequencies Eigenfrequencies
CONCLUSION
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call