Studies with a low-background germanium detector in the Holborn Underground laboratory

This paper reports on the performance and use of a low background HPGe detector, which was operated in the Holborn Underground laboratory from May 1990 to July 1993, and on some of the results obtained from it. The analysis includes sections on measuring the efficiency of the system and a discussion of the contributions to the background. Most of the materials studied were those being considered for use in the Solar Neutrino Observatory or in the UK Dark Matter programme. Results for the natural radioactivity in various classes of materials include those for the glass used in photomultipliers, the extent of non-equilibrium in the main decay series of thorium and uranium and the presence of protactinium in samples of zirconium oxide. There is also a summary of the cosmogenic isotopes found in the meteorite Glatton which fell in 1991.