Mechanical Correction of Frequency for Copper Base of Nb Sputtered QWR Cavity

Mechanical correction of frequency for copper base of Nb sputtered QWR cavitiy needs to take the change of frequency of cavity with temperature into account. The relationship between temperature and frequency of Nb sputtered QWR cavity was studied and verified at liquid nitrogen temperature, meanwhile the procedure of mechanical correction was optimized. The results show that final frequency error is controlled under 2 kHz for a 150 MHz Nb sputtered QWR cavity.