5 papers
The Ponderomotive Effects of Narrow-band, Superconducting Resonators in Open and Closed Loop
Jacob Brown, Alexander Sukhanov, Crispin Contreras-Martinez +7
In this work, we present measurements of ponderomotive instabilities in narrow-band, coaxial resonators in open and closed control loop systems. We show an analytical scheme we wil…
Impact of heat treatments on the performance of low-frequency superconducting quarter-wave resonators at 4.3 K
Jacob Brown, Sang-hoon Kim, Walter Hartung +1
We applied heat treatments to 80.5 MHz quarter-wave resonators made from bulk niobium and prepared with buffered chemical polishing BCP. We evaluated their performance at 4.3 K. We…
Two-port CW measurements on RF cavities: Notes on self-consistency assessment and indirect methods
Walter H. Hartung, Wei Chang, Sang-Hoon Kim +2
In the case of a radio-frequency (RF) cavity with a mismatched input coupler, a direct calculation of the power dissipation in the cavity and the intrinsic quality factor from cont…
Report on first plasma processing trial for a FRIB quarter-wave resonator cryomodule
Walter Hartung, Wei Chang, Yoo-Lim Cheon +6
Plasma processing has been shown to help mitigate degradation of the performance of superconducting radio-frequency cavities, providing an alternative to removal of cryomodules fro…
Improved high-gradient performance for medium-velocity superconducting half-wave resonators: Surface preparation and trapped flux mitigation
Yuting Wu, Kenji Saito, Alex Taylor +13
A development effort to improve the performance of superconducting radio-frequency half-wave resonators (SRF HWRs) is underway at the Facility for Rare Isotope Beams (FRIB), where…