arXiv subjects

Manuel Lebert

Publications and source records attributed to Manuel Lebert.

4 recordsLinked to original sources

arXiv2026

Characterisation of a Thick Pixelated Silicon Detector for Electron Spectroscopy of Neutron Beta Decay

Silicon detectors are commonly used for spectroscopy of low-energy particles. For electrons in the 1 MeV range, a rather large thickness of 2mm is required to entirely stop the electrons and commercial options are scarce. With the instrument PERC at the FRM II, we aim to measure beta spectra from polarised and unpolarised neutrons in order to determine the axial-vector coupling constant, the element $V_\textrm{ud}$ of the Cabibbo-Kobayashi-Maskawa quark-mixing matrix, and to search for hypothetical scalar and tensor contributions. We present the characterisation of a commercially available, pixelated detector to assess its suitability to measure the entire electron energy spectrum of free neutron beta decay.

physics.ins-det↗

arXiv2024

Investigations of Charge Collection and Signal Timing in a multi-pixel Silicon Drift Detector

Sterile neutrinos are a minimal extension of the Standard Model of particle physics and a promising candidate for dark matter if their mass is in the keV-range. The Karlsruhe Tritium Neutrino experiment (KATRIN), equipped with a novel multi-pixel silicon drift detector array, the TRISTAN detector, will be capable of searching for these keV-scale sterile neutrinos by investigating the kinematics of the tritium $\beta$-decay. This measurement will be performed after the completion of the neutrino mass measurement campaign. To detect a sterile neutrino signal with a high sensitivity, a profound understanding of the detector response is required. In this work, we report on the characterization of a 7-pixel TRISTAN prototype detector with a laser system. We present the experimental results obtained in high-resolution scans of the detector surface with a focused laser beam and demonstrate how the charge collection and the timing of the signals generated in the detector is related to the detector geometry. A comparison of the experimental data with simulations shows a good agreement.

physics.ins-det↗

arXiv2020

Hunting keV sterile neutrinos with KATRIN: building the first TRISTAN module

The KATRIN (Karlsruhe Tritium Neutrino) experiment investigates the energetic endpoint of the tritium beta-decay spectrum to determine the effective mass of the electron anti-neutrino. The collaboration has reported a first mass measurement result at this TAUP-2019 conference. The TRISTAN project aims at detecting a keV-sterile neutrino signature by measuring the entire tritium beta-decay spectrum with an upgraded KATRIN system. One of the greatest challenges is to handle the high signal rates generated by the strong activity of the KATRIN tritium source while maintaining a good energy resolution. Therefore, a novel multi-pixel silicon drift detector and read-out system are being designed to handle rates of about 100 Mcps with an energy resolution better than 300 eV (FWHM). This report presents succinctly the KATRIN experiment, the TRISTAN project, then the results of the first 7-pixels prototype measurement campaign and finally describes the construction of the first TRISTAN module composed of 166 SDD-pixels as well as its implementation in KATRIN experiment.

physics.ins-det↗

arXiv2020

Characterization of the Detector Response to Electrons of Silicon Drift Detectors for the TRISTAN Project

Right-handed neutrinos are a natural extension of the Standard Model of particle physics. Such particles would only interact through the mixing with the left-handed neutrinos, hence they are called sterile neutrinos. If their mass were in the keV-range they would be Dark Matter candidates. By investigating the electron spectrum of the tritium beta-decay the parameter space with masses up to the endpoint of 18.6 keV can be probed. A sterile neutrino manifests as a kink-like structure in the spectrum. To achieve this goal the TRISTAN project develops a new detector system for the KATRIN experiment that can search for these new particles using the silicon drift detector technology. One major effect on the performance of the detectors is the so called dead layer. Here, a new characterization method for the prototype detectors is presented using the Kr-83m decay conversion electrons. By tilting the detector its effective dead layer increases, which leads to different peak positions. The difference of peak positions between two tilting angles is independent of source effects and is thus suitable for characterization.A dead layer is then extracted by comparing the measurements to Monte-Carlo simulations. A dead layer in the order of 50 nm was found.

physics.ins-det↗