摘要
In this paper, a new mechanism of electromagnetic instability, the induced ion-channel instability, is stud- ied. It is based on the transverse driven betatron oscillation of relativistic electron beam induced by an additional magnetic undulator with a period close to the betatron wavelength in an ion channel. As its amplitude is sensitive to the electron beam energy, the driven betatron oscillation may determine electron beam grouping in the ponderomotive potential by selecting the undulator strength and period, and it provides a new mechanism of electron bunching, re- sulting in electromagnetic instability. Under proper condition, a new free-electron laser based on this mechanism may be realized.
In this paper, a new mechanism of electromagnetic instability, the induced ion-channel instability, is stud- ied. It is based on the transverse driven betatron oscillation of relativistic electron beam induced by an additional magnetic undulator with a period close to the betatron wavelength in an ion channel. As its amplitude is sensitive to the electron beam energy, the driven betatron oscillation may determine electron beam grouping in the ponderomotive potential by selecting the undulator strength and period, and it provides a new mechanism of electron bunching, re- sulting in electromagnetic instability. Under proper condition, a new free-electron laser based on this mechanism may be realized.
基金
Partially supported by the Major State Basic Research Development Programme of China under Grant No.2002CB713600,the Shanghai Science and Technology Council under Grant No.02QF14059and the Exploration Project of Knowledge Innovation Program of CAS.
