ISBN 9783843938365

978-3-8439-3836-5, Reihe Physik

Jan Mayer
Charting NeuLAND: Towards multi-neutron reconstruction with the New Large Area Neutron Detector and The virtual γ-ray spectrometer G4Horus

133 Seiten, Dissertation Universität Köln (2018), Softcover, A5

Zusammenfassung / Abstract

This thesis presents work on the New Large Area Neutron Detector NeuLAND, which will be used at the upcoming Facility for Antiproton and Ion Research (FAIR), Germany. Assembly steps for detector modules are described, followed by experiments performed with the NeuLAND Demonstrator in Japan. The detector is also assembled virtually for Monte Carlo simulations, including a conversion process from energy depositions to experimental look-alike events. This detector response is in good agreement with experimental data from Japan. Performance and behavior of newly developed reconstruction methods are mapped out for different detector sizes. These algorithms can reconstruct multiplicity and primary interaction points for many incoming neutrons. In addition, the groundwork for event reconstruction with neural networks is laid.

In the second part, the Geant4 application G4Horus is presented, which implements a virtual version of the HORUS γ-ray spectrometer used at the Institute for Nuclear Physics, University of Cologne. The high purity germanium (HPGe) detectors in this spectrometer are often used to measure γ-rays from 5 MeV to 10 MeV. No standardized calibration sources are available at these energies, and the efficiency calibration is challenging. G4Horus alleviates this problem with easy to use efficiency simulations. More complex experiments with particle detectors and respective data analysis procedures can be understood and improved with matching simulations. Here, G4Horus provides listmode data with simulated particle-γ coincidences.