Beschreibung:
<jats:p>We describe the construction of a 35-GHz split high-Q superconducting cavity operating in the TM010 mode. The cavity is tuned by varying the spacing between the halves. Radiation loss from this gap is suppressed by a choke groove. Q=4×107 has been achieved in both lead-plated copper and niobium cavities at a temperature of 2 K. Q&gt;107 can be maintained over a 300-MHz tuning range, corresponding to a gap between the halves of 85 μm.</jats:p>