Low temperature bolometers for experiments with cooled heavy ion beams from storage rings

The development of calorimetric low temperature detectors for the energy sensitive detection of heavy ions is discussed. Due to its high intrinsic energy resolution this detector type promises to be a useful tool for nuclear physics experiments with cooled heavy ion beams from storage rings. Detector tests performed with relativistic heavy ions from the SIS synchrotron at GSI yielded relative energy resolutions of 2 - 4 · 10 ^-3 for ²⁰Ne and for ²⁰⁹Bi ions, limited in this case by the energy spread of the beam. In a first application of such detectors the excitation of the giant resonance in lead nuclei via the reaction ^natPb ( ²⁰Ne, ²⁰Ne') ^natPb ^∗ was investigated by separating inelastically from elastically scattered ²⁰Ne ions in the energy spectrum. At a scattering angle of Θ_Lab=3° the excitation energy and the strength of the giant resonance were found to be in good agreement with theoretical predictions. In a recent experiment calorimetric detectors were bombarded with cooled ²³⁸U ions at E = 360 MeV/u, extracted from the storage ring ESR. An energy resolution of ΔE = 97 MeV, corresponding to a relative resolution of Δ {E}/{E} = 1.1 · 10 ^-3, was obtained.