Publications [#167641] of Ying Wu

Papers Published
  1. W. Z. Wu, Y. Kim, J. Li, Ping Wang, Matthew Busch, Gary Swift, Ying K. Wu, Dmitry Teytelman, In-Soo Park, In Soo Ko, Development and commissioning of bunch-by-bunch longitudinal feedback system for Duke storage ring, Proceedings of 2009 Particle Accelerator Conference (2009), pp. 4117-4119 .

    The cou­pled bunch mode in­sta­bil­i­ties (CBMIs) caused by vac­u­um cham­ber impedance limit and de­grade the per­for­mance of the stor­age ring based light sources. A bunch-by-bunch lon­gi­tu­di­nal feed­back (LFB) sys­tem has been de­vel­oped to sta­bi­lize beams for the op­er­a­tion of a stor­age ring based Free Elec­tron Laser (FEL) and the High In­ten­si­ty Gam­ma-ray Source (HIGS) at the Duke stor­age ring. Em­ploy­ing a Gi­ga-sam­ple FPGA based pro­ces­sor (iGP), the LFB is ca­pa­ble of damp­ing out the dipole mode os­cil­la­tion for all 64 bunch­es. As a crit­i­cal sub­sys­tem of the LFB sys­tem, kick­er cav­i­ty is de­vel­oped with a cen­ter fre­quen­cy of 938 MHz, a wide band­width (> 90 MHz), and a high shunt impedance (> {10}00 Ω). First com­mis­sioned in sum­mer 2008, the LFB has been op­er­at­ed to sta­bi­lize high cur­rent mul­ti-bunch op­er­a­tion. More re­cent­ly, the LFB sys­tem is demon­strat­ed as a crit­i­cal in­stru­ment to en­sure sta­ble op­er­a­tion of the HIGS with a high in­ten­si­ty gamma beam above 20 MeV with a fre­quent top-off in­jec­tion to com­pen­sate for the sub­stan­tial and con­tin­u­ous elec­tron beam loss in the Comp­ton scat­ter­ing pro­cess. In the fu­ture, we will per­form de­tailed stud­ies of the impedance ef­fects using the LFB sys­tem.