Berlin 2012 – wissenschaftliches Programm

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TT: Fachverband Tiefe Temperaturen

TT 33: Superconductivity, Measuring Devices, Matter at Low Temperature: Poster Session

TT 33.66: Poster

Mittwoch, 28. März 2012, 15:00–19:00, Poster B

Development of a large-area detector for position and energy resolving detection of molecular fragments — •Alexandra Kampkötter, Andreas Fleischmann, Loredana Gastaldo, Sebastian Kempf, Andreas Pabinger, Christian Pies, Sönke Schäfer, Thomas Wolf, and Christian Enss — Kirchhoff-Institut für Physik, INF 227, 69120 Heidelberg

The recombination of a molecular cation with an electron, followed by fragmentation, is a fundamental reaction in cold, dilute plasmas and plays a key role in interstellar chemistry. To investigate such reactions in laboratory environment with full quantum control, the Max-Planck Institute for Nuclear Physics in Heidelberg is building a cryogenic storage ring to prepare molecular ions in their groundstate. The full kinematics of these recombination processes can be resolved by a position and energy sensitive detection of the reaction products/molecule fragments. We describe the development of a new large-area MMC for position sensitive detection of massive particles with kinetic energies down to a few keV. The detector encompasses sixteen pie-shaped large-area absorbers to form a circular whole with a diameter of 36mm. The temperature sensor is positioned on the outer edge of each absorber. The rise-time of the detector signals varies with the impact location of the particle due to diffusive expansion of heat in the absorbers. We present results of first test measurements where energy was deposited in the absorber at different positions by light pulses from three LEDs. The observed position dependence of the signal shapes agrees well with the one expected from detailed thermal simulations.