The 500 MHz 5-cell superconducting RF(SRF) cavity was designed aiming to be a candidate cavity for high current accelerators. A copper prototype cavity and a niobium cavity were fabricated at SINAP in 2012. In order t...The 500 MHz 5-cell superconducting RF(SRF) cavity was designed aiming to be a candidate cavity for high current accelerators. A copper prototype cavity and a niobium cavity were fabricated at SINAP in 2012. In order to ensure these cavities get the desired frequency and a good field flatness higher than 98%, frequency control was implemented in the manufacturing process and pre-tuning has been done using a simple pre-tuning frame based on the bead-pull pre-tuning method. Then, TM010-π mode frequency within 5 kHz from the target frequency was achieved and the field flatness reached 98.9% on the copper prototype cavity. Finally, the same procedure was applied to the niobium cavity to obtain a field flatness better than 98% which benefited the cavity performance in the vertical testing.展开更多
Surface preparation is an important processing in production procedures of superconducting niobium cavities,deciding whether the performance of the niobium cavities can meet the specifications. A series of surface pre...Surface preparation is an important processing in production procedures of superconducting niobium cavities,deciding whether the performance of the niobium cavities can meet the specifications. A series of surface preparation methods and relevant apparatuses have been constructed at Shanghai Institute of Applied Physics(SINAP) and the standard procedures of cavity processing were established and successfully applied to different types of cavities. With standard surface preparation procedures on the 500 MHz 5-cell niobium cavity, the cavity accelerating voltage at T = 4.2 K reached 7.5 MV while its quality factor was still higher than 1 × 109.The accelerating gradient of the IMP-HWR010 cavity reached 4.9 MV/m with the quality factor of better than3 × 108 at 4.2 K.展开更多
文摘The 500 MHz 5-cell superconducting RF(SRF) cavity was designed aiming to be a candidate cavity for high current accelerators. A copper prototype cavity and a niobium cavity were fabricated at SINAP in 2012. In order to ensure these cavities get the desired frequency and a good field flatness higher than 98%, frequency control was implemented in the manufacturing process and pre-tuning has been done using a simple pre-tuning frame based on the bead-pull pre-tuning method. Then, TM010-π mode frequency within 5 kHz from the target frequency was achieved and the field flatness reached 98.9% on the copper prototype cavity. Finally, the same procedure was applied to the niobium cavity to obtain a field flatness better than 98% which benefited the cavity performance in the vertical testing.
基金Supported by the National Natural Science Foundation of China(No.11205233)
文摘Surface preparation is an important processing in production procedures of superconducting niobium cavities,deciding whether the performance of the niobium cavities can meet the specifications. A series of surface preparation methods and relevant apparatuses have been constructed at Shanghai Institute of Applied Physics(SINAP) and the standard procedures of cavity processing were established and successfully applied to different types of cavities. With standard surface preparation procedures on the 500 MHz 5-cell niobium cavity, the cavity accelerating voltage at T = 4.2 K reached 7.5 MV while its quality factor was still higher than 1 × 109.The accelerating gradient of the IMP-HWR010 cavity reached 4.9 MV/m with the quality factor of better than3 × 108 at 4.2 K.
