• Keckert, S.; Junginger, T.; Knobloch, J.; Kugeler, O.: The challenge to measure nΩ surface resistance on SRF samples. In: Shane Koscielniak ... [Ed.] : IPAC2018 : Proceedings of the 9th International Particle Accelerator Conference, Vancouver, Canada, April 29–May 4, 2018Geneve: JaCoW, 2018. - ISBN 978-3-95450-184-7, p. WEPML049/1-4
    http://ipac2018.vrws.de/papers/wepml049.pdf

Open Access Version

Abstract:
Systematic research on fundamental limits of super-conducting materials for SRF applications and their intrinsic material properties relevant for use in an ac-celerator requires studies in a wide parameter space of temperature, RF field and frequency. The Quadrupole Resonator at HZB enables precision measurements on planar samples at temperatures of 1.8 K to >20 K, RF fields of up to 120 mT and frequencies of 420 MHz, 850 MHz and 1285 MHz. In the past years, the capa-bilities of the setup were studied intensively and de-veloped further. Sources of systematic errors, such as microphonics or misalignment have been identified and eliminated. In this contribution the current status of the QPR and its systematic limitations are discussed.