SERIES ARRAY OF SUPERCONDUCTING TUNNEL-JUNCTIONS AS PHONON SENSOR IN A DARK-MATTER DETECTOR

A design of a cryogenic detector for a WIMP dark matter search based o n a single crystal absorber using Series Array of Superconducting Tunn el Junctions (SASTJs) as readout sensors has been presented. In order to investigate the behaviour of such a detector the response of two sp atially separated Series Arrays of Superconducting Tunnel Junctions (S ASTJs) to the non-equilibrium phonons generated in a single crystal of BaF2, by external alpha-particles has been measured. A strong positio n dependence in pulse height and pulse shape of the detector response has been observed. The fast time response of the SASTJs permits time r esolved measurements of the spatially separated particle interactions in the crystal.