Speaker
Description
The Spallation Neutron Source (SNS) Drift Tube Linac (DTL) employs iris couplers to efficiently deliver RF power into the accelerating structure. To support the development, tuning, and high-power conditioning of these couplers prior to installation in the actual DTLs, a dedicated test cavity and an iris-to-coaxial transition structure have been designed. This work presents the electromagnetic design, simulation, and optimization of the test setup, enabling precise characterization of the iris coupler’s performance. The transition structure allows for tuning of the iris opening dimensions without requiring a waveguide taper or full-size waveguide transitions, while maintaining impedance matching between the coaxial feed and the iris geometry to minimize reflection and power loss. During low-power tests, the iris opening dimensions can be evaluated using the iris-to-coaxial transition attached to the test cavity. For high-power conditioning, full-size waveguides with ceramic vacuum windows are connected to the test cavity to replicate operational conditions. Key design parameters were optimized using CST Studio Suite, and sensitivity studies were conducted to assess the impact of mechanical tolerances on RF performance. The resulting test platform provides a reliable and efficient means for tuning and validating iris couplers, contributing to improved operational stability and RF efficiency in the SNS DTL.
Funding Agency
- ORNL is managed by UT-Battelle, LLC, under contract DE-AC05-00OR22725 for the U.S. Department of Energy. This research was supported by the DOE Office of Science, Basic Energy Science, Scientific Us
| Paper status | Proceeding files received |
|---|