Download
1 / 6
60 likes | 172 Vues
Beam dynamics simulations indicate that the impedance of non-operating cavities can significantly degrade beam quality during high current operations. To mitigate this, we propose equipping cavity gaps with fast, high power switches that establish a short circuit with low intrinsic impedance. Preliminary tests with the Behlke HTS 301-12-AC-B Mosfet switch show promising results; however, dielectric loss caused isolation material damage. Future steps include isolation with oil, low-level prototype tests, and a design for impedance reduction networks, addressing both operational and organizational challenges.
E N D
Problem Description Beam dynamics simulations have shown that the impedance of the non-operating cavities may degrade the quality of the circulating beam at high current operation significantly. Solution Equip the gaps of the non operating cavities with fast high power switches, generating a short circuit with low intrinsic impedance. Technical Description
First Tests with MosFet Gap Switch (Behlke HTS 301-12-AC-B + Cooling Fins,Category VII) Breakdown at 12 kV RF-amplitude (1 MHz) after 3 minutes (open) Due to dielectric losses, the isolation material at the high voltage output has started to boil. The isolation was damaged, but not the semiconductors. Average of 50 W reached (closed) A resistive resistance of 10 W reached RF-characteristics of the switch ok Next Step Isolation of the switch with oil Status of R&D
Work Sharing GSI Specification for manufacturing the switch Low-level tests Prototype cavity tests (0.8...5.4 MHz) CERN Prototype cavity tests (2.8...10 MHz) Design of passive network for impedance reduction Shielding experiments for improvement of radiation hardness Tentative schedule for 2005 available Organizational Issues
Personnel not yet available → 5...6 months shifted Schedule (Description of Work)
