In this paper,the slow orbit feedback system of HLS,including the feedback principle,the hardware,the software and the main operation results,is briefly introduced.With the help of slow orbit feedback system,the verti...In this paper,the slow orbit feedback system of HLS,including the feedback principle,the hardware,the software and the main operation results,is briefly introduced.With the help of slow orbit feedback system,the vertical orbit stability of HLS is better than 30 microns,which meets the requirement of synchrotron radiation users and is comparable with the international advanced level of orbit stability in the same kind of machines.展开更多
BBU(Beam breakup)instability once appeared in the early stage of 'Dragon-Ⅰ' LIA,which was excited by TM_(110)mode stimulated when the eccentric beam passed through the multi-functional cavity(MFC).The radio f...BBU(Beam breakup)instability once appeared in the early stage of 'Dragon-Ⅰ' LIA,which was excited by TM_(110)mode stimulated when the eccentric beam passed through the multi-functional cavity(MFC).The radio frequency characteristics of MFC were analyzed with three methods such as analytic calculation,numerical computation,and measurement.The frequency of the TM_(110)mode from these methods agreed with the experimental results,while the transverse coupling impedance was different from the experimental results by some times.The main BBU exciter was the big transverse coupling impedance of the MFC which could be concluded.A grid was designed to shield the gap of the MFC.The experiments show that the BBU was compressed and the high frequency oscillation disappeared.展开更多
文摘In this paper,the slow orbit feedback system of HLS,including the feedback principle,the hardware,the software and the main operation results,is briefly introduced.With the help of slow orbit feedback system,the vertical orbit stability of HLS is better than 30 microns,which meets the requirement of synchrotron radiation users and is comparable with the international advanced level of orbit stability in the same kind of machines.
文摘BBU(Beam breakup)instability once appeared in the early stage of 'Dragon-Ⅰ' LIA,which was excited by TM_(110)mode stimulated when the eccentric beam passed through the multi-functional cavity(MFC).The radio frequency characteristics of MFC were analyzed with three methods such as analytic calculation,numerical computation,and measurement.The frequency of the TM_(110)mode from these methods agreed with the experimental results,while the transverse coupling impedance was different from the experimental results by some times.The main BBU exciter was the big transverse coupling impedance of the MFC which could be concluded.A grid was designed to shield the gap of the MFC.The experiments show that the BBU was compressed and the high frequency oscillation disappeared.
