Author: Cao, Y.
Paper Title Page
MOCOAK01 SECRAL Status and First Beam Test at 24GHz 1
 
  • H.W. Zhao, Y. Cao, Y.C. Feng, X.H. Guo, J.Y. Li, W. Lu, L.T. Sun, D. Xie, X.Z. Zhang, H. Zhao
    IMP, Lanzhou, People's Republic of China
  
  SE­CRAL has been in rou­tine op­er­a­tion at 18GHz for HIRFL (Heavy Ion Re­search Fa­cil­i­ty in Lanzhou) ac­cel­er­a­tor com­plex since May 2007. It has de­liv­ered many high­ly charged heavy ion beams for the HIRFL ac­cel­er­a­tor and the total beam time so far has ex­ceed­ed 3000 hours. To fur­ther en­hance the SE­CRAL per­for­mance, a 24GHz/7kW gy­rotron mi­crowave am­pli­fi­er has been in­stalled and test­ed. Very ex­cit­ing re­sults were pro­duced with quite a few new record high­ly-charged ion beam in­ten­si­ties. Brem­strahlung mea­sure­ments at 24GHz have shown that X-ray is much stronger at high­er RF fre­quen­cy, high­er RF power and high­er min­i­mum B field. Beam emit­tance study has been con­duct­ed in order to im­prove the beam bright­ness. An ad­di­tion­al cryo­stat with five GM cry­ocool­ers was in­stalled atop the SE­CRAL to liq­ue­fy the boil-off he­li­um gas to min­i­mize the liq­uid he­li­um con­sump­tion. The lat­est re­sults and re­li­able long-term op­er­a­tion for the ac­cel­er­a­tor have once again demon­strat­ed that SE­CRAL is one of the best per­for­mance ECR ion source for the pro­duc­tion of high­ly-charged heavy ion beams. De­tailed and fu­ture de­vel­op­ments of SE­CRAL will be pre­sent­ed.  
slides icon Slides MOCOAK01 [4.739 MB]  
 
TUPOT009 Measurements of Bremsstrahlung Radiation and X-Ray Heat Load to Cryostat on SECRAL 134
 
  • H. Zhao, Y. Cao, X.X. Li, D. Xie, W.H. Zhang, X.Z. Zhang, H.W. Zhao, Y.H. Zhu
    IMP, Lanzhou, People's Republic of China
  • W. Lu
    Graduate School of the Chinese Academy of Sciences, Beijing, People's Republic of China
  
  Mea­sure­ment of Bremsstrahlung ra­di­a­tion from ECR plas­ma can yield cer­tain in­for­ma­tion of the ECR heat­ing pro­cess and a plau­si­ble es­ti­mate of the X-ray heat load to the cryo­stat of a su­per­con­duct­ing ECR source which needs se­ri­ous­ly ad­dressed. With a new­ly-de­vel­oped col­li­ma­tion sys­tem, which de­fines a nar­row­er spa­tial range of the mea­sure­ment and pro­vides an ef­fec­tive shield­ing from the back­ground, a sys­tem­at­ic mea­sure­ment of the Bremm­strahlung emit­ted ax­i­al­ly from the SE­CRAL (Su­per­con­duct­ing ECR Ion Source with Ad­vanced de­sign in Lanzhou) plas­ma were car­ried out re­cent­ly. The spec­tral tem­per­a­ture Tspe, a rel­a­tive index of mean en­er­gy of the plas­ma hot elec­trons, was de­rived through lin­ear fit­ting of the spec­tra in se­mi-log­a­rithm co­or­di­nates. This ar­ti­cle will pre­sent and dis­cuss the evo­lu­tions of the X-ray flux and the hot elec­tron en­er­gy with var­i­ous source pa­ram­e­ters, such as heat­ing fre­quen­cy, RF power and mag­net­ic field con­fig­u­ra­tion. And pos­si­ble so­lu­tions to re­duce the X-ray heat load in­duced by Bremsstrahlung ra­di­a­tion are pro­posed and dis­cussed.  
poster icon Poster TUPOT009 [1.581 MB]