Seminars/Colloquia

Garchinger Maier-Leibnitz-Kolloquium: Development and Operation of Next-Generation Low-Temperature Detectors for the COSINUS Dark Matter Search

by Dr Moritz Kellermann (Physik Department E15, TUM)

Europe/Berlin
Lecture Hall, ground floor (west) (LMU building, Am Coulombwall 1, campus Garching)

Lecture Hall, ground floor (west)

LMU building, Am Coulombwall 1, campus Garching

Description

COSINUS is a new experiment that will carry out a model-independent cross-check of the DAMA/LIBRA dark matter result by operating sodium iodide (NaI) as a low-temperature detector at milli-Kelvin temperatures. By equipping absorbers with transition edge sensors (TESs), it is possible to read out the heat created in particle recoils in addition to the emitted scintillation light. Since the deposition of a TES on NaI is not possible with the currently available technology, an alternative layout, the remoTES, was developed. Here, the sensor is deposited on a separate wafer and connected to the absorber via a gold link, enabling the readout of delicate crystals with high fabrication standards and reproducibility. To operate the COSINUS detectors, a modern facility, equipped with a custom-made dry dilution refrigerator, was built underground at Laboratori Nazionali del Gran Sasso. It was designed to minimize one of the largest noise sources in low-temperature detectors: vibrations in the acoustic frequency range. In this talk, I will present the studies that motivate the final design of the COSINUS detector modules, as well as the facility to operate them. Furthermore, I'll present the design and performance of a dedicated spring-based passive decoupling system operating at the detector level within the dilution refrigerator.

Hybrid access via ZOOM:
https://lmu-munich.zoom.us/j/98457332925?pwd=TWc3V1JkSHpyOTBPQVlMelhuNnZ1dz09
Meeting ID: 984 5733 2925
Passcode: 979953

 

Organized by

Peter Thirolf (LMU) / Norbert Kaiser (TUM)