Beta irradiation of a geometrically metastable superconducting strip detector with a magnetic flux penetration read-out

Geometrical metastability, observed in superconducting type I tin flat strips, has been previously proposed as a principle for particle detection. The energy deposition of an incoming β-particle induces the rupture of the metastability and consequently the penetration of multiquantum flux tubes into a superconducting tin strip. We present here the first absorption spectra from two beta sources, which demonstrate the linearity and energy-resolution of these detectors.