Author: Chi, Y.L.
Paper Title Page
MOPS033 Beam Dynamics Studies on the 100 MeV/100 kW Electron Linear Accelerator for NSC KIPT Neutron Source 673
 
  • S. Pei, Y.L. Chi, M. Hou, W.B. Liu, G. Pei, S.H. Wang, Z.S. Zhou
    IHEP Beijing, Beijing, People's Republic of China
  • N. Aizatsky, I.M. Karnaukhov, V.A. Kushnir, V. Mitrochenco, A.Y. Zelinsky
    NSC/KIPT, Kharkov, Ukraine
  
  We de­signed one 100MeV/100kW elec­tron lin­ear ac­cel­er­a­tor for NSC KIPT, which will be used to drive a neu­tron source on the base of sub­crit­i­cal as­sem­bly. Beam dy­nam­ics stud­ies has been con­duct­ed to reach the de­sign re­quire­ment (E=100MeV, P=100kW, dE/E<1% for 99% par­ti­cles). In this paper, we will pre­sent the progress of the de­sign and dy­nam­ics sim­u­la­tion re­sults. For high in­ten­si­ty and long beam pulse lin­ear ac­cel­er­a­tors, BBU ef­fect is one big issue; spe­cial care has been taken in the ac­cel­er­at­ing struc­ture de­sign. To sat­is­fy the en­er­gy spread re­quire­ment at the linac exit, the par­ti­cles with large en­er­gy dif­fer­ence from the syn­chronous par­ti­cle should be elim­i­nat­ed at low en­er­gy stage to ease the de­sign of the col­li­ma­tion sys­tem and ra­di­a­tion shield­ing. A dis­per­sion free chi­cane with 4 bend­ing mag­nets is in­tro­duced at the down­stream of the 1st ac­cel­er­at­ing sec­tion; the un­want­ed par­ti­cles will be col­li­mat­ed there.  
 
TUXA01 Status and Challenges of the China Spallation Neutron Source 889
 
  • S. Fu, H. Chen, Y.W. Chen, Y.L. Chi, H. Dong, L. Dong, S.X. Fang, K.X. Huang, W. Kang, J. Li, L. Ma, H.F. Ouyang, H. Qu, H. Sun, J. Tang, C.H. Wang, Q.B. Wang, S. Wang, T.G. Xu, Z.X. Xu, X. Yin, C. Zhang, J. Zhang
    IHEP Beijing, Beijing, People's Republic of China
  
  The ac­cel­er­a­tor com­plex of China Spal­la­tion Neu­tron Source (CSNS) main­ly con­sists of an H− linac of 80 MeV and a rapid-cy­cling syn­chrotron of 1.6 GeV. It op­er­ates at 25 Hz rep­e­ti­tion rate with an ini­tial pro­ton beam power of 100 kW and is up­grade­able to 500kW. The pro­ject will start con­struc­tion in the mid­dle of 2011 with a con­struc­tion pe­ri­od of 6.5 years. The CSNS ac­cel­er­a­tor is the first large-scale, high-pow­er ac­cel­er­a­tor pro­ject to be con­struct­ed in China and thus we are fac­ing a lot of chal­lenges. This paper pre­sents the cur­rent sta­tus of CSNS pro­ject and sum­ma­rizes the tech­nol­o­gy de­vel­op­ment dur­ing the past sev­er­al years.  
slides icon Slides TUXA01 [3.444 MB]  
 
TUPC034 Design Studies on 100 MeV/100 kW Electron Linac for NSC KIPT Neutron Source on the Base of Subcritical Assembly Driven by Linac 1075
 
  • Y.L. Chi, J. Cao, X.W. Dai, C.D. Deng, M. Hou, X.C. Kong, R.L. Liu, W.B. Liu, C. Ma, G. Pei, H. Song, S.H. Wang, G. Xu, J. Zhao, Z.S. Zhou
    IHEP Beijing, Beijing, People's Republic of China
  • M.I. Ayzatskiy, I.M. Karnaukhov, V.A. Kushnir, V.V. Mytrochenko, A.Y. Zelinsky
    NSC/KIPT, Kharkov, Ukraine
  • S. Pei
    IHEP Beijng, Beijing, People's Republic of China
  
  In NSC KIPT, Kharkov, Ukraine, a neu­tron source on the base of sub­crit­i­cal as­sem­bly driv­en by 100 MeV/100 kW elec­tron lin­ear ac­cel­er­a­tor is under de­sign and de­vel­op­ment. To pro­vide neu­tron flux value of about 1013 neu­tron/s the elec­tron lin­ear ac­cel­er­a­tor with 100 MeV beam and av­er­age beam power of 100 kW will be used. Con­struc­tion and man­u­fac­ture of the lin­ear ac­cel­er­a­tor of such high beam in­ten­si­ty with low emit­tance and beam loss­es is a chal­leng­ing task. In the re­port the pro­ject of the elec­tron lin­ear ac­cel­er­a­tor of the re­quired beam en­er­gy and in­ten­si­ty is de­scribed. The ac­cel­er­a­tor struc­ture and main tech­ni­cal so­lu­tions are pre­sent­ed. To over­come the BBU ef­fect of this high av­er­age beam cur­rent, sev­er­al ef­fec­tive mea­sures are adopt, such as using con­stant gra­di­ent struc­ture to spread the HOMs fre­quen­cies dif­fer­ent cells, larg­er inner ra­dius and short­er sec­tion length make the high­er group ve­loc­i­ty and op­ti­mize the struc­ture ge­om­e­try to keep the shunt impedance as good as pos­si­ble. After the beam bunch­ing sys­tem, a chi­cane is fol­lowed to chop­per the beam to avoid the beam lost in the high­er en­er­gy part.  
 
THPZ012 Luminosity Enhancement and Performance in BEPCII 3708
 
  • Q. Qin, J. Cao, J. Cheng, Y.L. Chi, H. Dong, Z. Duan, D. Ji, W. Kang, S.P. Li, L. Ma, H. Qu, C.H. Wang, G.W. Wang, J.Q. Wang, X.H. Wang, Y. Wei, J. Xing, G. Xu, C.H. Yu, J. Yue, C. Zhang, Y. Zhang
    IHEP Beijing, Beijing, People's Republic of China
  
  The Bei­jing Elec­tron Positron Col­lid­er (BEPC) was up­grad­ed to a fac­to­ry-like ma­chine –- BEPCII, dur­ing last sev­er­al years. From last Novem­ber, the BEPCII was com­mis­sioned again for its lu­mi­nos­i­ty. Ef­forts on op­tics cor­rec­tion in­clud­ing op­ti­miz­ing the strengths of su­per­con­duct­ing quadrupoles near the IP, or­bits cor­rec­tion con­cern­ing beam en­er­gy, etc, make the transvers tunes pos­si­ble to move very close to half in­te­ger, bring­ing a big lu­mi­nos­i­ty in­crease. The back­ground of the de­tec­tor is also re­duced with beam com­mis­sion­ing, and fi­nal­ly fit the re­quire­ments of data tak­ing. Fur­ther lu­mi­nos­i­ty com­mis­sio­ing, in­clud­ing cou­pling op­ti­miza­tion, be­ta-waist tun­ing, was car­ried on, and the lu­mi­nos­i­ty reached 6.49·1032 cm-2 s-1 dur­ing rou­tine op­er­a­tion. Some mea­sures of lu­mi­nos­i­ty en­hance­ment and the lu­mi­nos­i­ty re­lat­ed ac­cel­er­a­tor physics is­sues will be dis­cussed.