HOM End Groups

An end group for a higher-order mode (HOM) absorber is the specially designed termination section at the end of the absorber. The primary role of an end group is to ensure efficient absorption of the HOM power. This is accomplished by careful impedance matching to prevent reflections back into the accelerator cavity and by appropriate material selection to optimize RF power dissipation.

Our HOM end groups feature the following:

  • Multi-convolution bellows for thermal growth absorption, increasing the thermal path length, and taking up any deviation of cavity flanges from nominal

  • 5 K intercept to reduce heat into < 2 K system

  • Copper-plated beam tube to reduce resistive heating

  • Tapered beam tube to match HOM diameter to cavity diameter

  • G10 standoffs to prevent any metal-to-absorber contact or dust creation, while allowing bellows to expand to take up thermal growth and mechanical tolerances

Questions? Contact us to learn more.