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ZnO-based ceramics are known as promising scintillators exhibiting light emission in the ultraviolet (UV) spectral region (~390 nm) and ultrafast decay times (1 ns). They are of great interest for applications in scintillation counters and screens at high-energy heavy ion accelerators. In this contribution, the deterioration of scintillating properties of ZnO-based ceramics subjected to heavy ion exposure at high doses is investigated. The scintillation light spectra of ZnO(In) as a function of fluence for 4.8 MeV/u 48Ca and 197Au ions were studied. We observed that the deterioration of the scintillation intensity with increasing fluence follows the Birks-Black model., Proceedings of the 11th International Beam Instrumentation Conference, IBIC2022, Kraków, Poland

The quality of slowly, typically several seconds, extracted beams from the GSI synchrotron SIS18 is characterized with respect to the temporal beam stability, the so-called spillμstructure on the 100 µs scale. A pilot experiment was performed utilizing transverse emittance exchange to reduce the beam size in the extraction plane, and the improvement of spillμstructure was found. Important beam instrumentation comprises an Ionization Profile Monitor for beam profile measurement inside the synchrotron and a plastic scintillator at the external transfer line for ion counting with up to several 10⁶ particles per second and 20 µs time slices. The performant data acquisition systems, including a scaler and a fast Time-to-Digital Converter (TDC), allow for determining the spill quality. The application of the TDC in the measurement and related MAD-X simulations are discussed., Proceedings of the 11th International Beam Instrumentation Conference, IBIC2022, Kraków, Poland

An exploration into the application of three machine learning (ML) approaches to identify and separate events in the detectors used for particle counting at the GSI Helmholtz Centre for Heavy Ion Research. A convolutional neural network (CNN), a shape-based template matching algorithm (STMF) and Peak Property-based Counting Algorithm (PPCA) were developed to accurately count the number of particles without domain-specific knowledge required to run the currently used algorithm. The three domain-agnostic ML algorithms are based on data from scintillation counters commonly used in beam instrumentation and represent proof-of-work for an automated particle counting system. The algorithms were trained on a labelled set of over 150 000 experimental particle data. The results of the three classification approaches were compared to find a solution that best mitigates the effects of particle pile-ups. The two best-achieving algorithms were the CNN and PPCA, achieving an accuracy of 99.8\%., Proceedings of the 11th International Beam Instrumentation Conference, IBIC2022, Kraków, Poland

At present the Facility for Antiproton and Ion Research (FAIR) is under construction at the GSI site. As part of the FAIR project the beamlines of the High Energy Beam Transport (HEBT) section interconnect the synchrotrons, storage rings and experimental caves. The large range of beam energies (MeV to GeV) and beam intensities up to 10¹² particles per pulse for uranium, or up to 2·10¹³ particles per pulse for protons, demand in many cases for purpose-built beam diagnostic devices. Presently, the main diagnostic components are being manufactured by international in-kind partners in close collaboration with GSI. This contribution presents an overview of the beam instrumentation layout of the FAIR HEBT and summa-rizes the present status of developments for HEBT beam diagnostics. We focus on the status of the foreseen beam current transformers, particle detectors, scintillating screens and profile grids., Proceedings of the 8th International Beam Instrumentation Conference, IBIC2019, Malmö, Sweden

At GSI ion beams of many elements, from H up to U, are produced with energy as high as 4.5 GeV/u with the SIS-18 synchrotron. For absolute beam intensity and micro-spill structure measurements a BC400 organic scintillator is used. Due to the low radiation hardness of this material, alternative inorganic scintillators like ZnO:Ga and ZnO:In were investigated. The properties and possible application of these novel radiation hard fast scintillators will be discussed. Their response to Sn, Xe and U ion beams will be reported., Proceedings of the 8th International Beam Instrumentation Conference, IBIC2019, Malmö, Sweden

Journal of physics / Conference Series Conference Series 1067, 072002 (2018). doi:10.1088/1742-6596/1067/7/072002, This contribution deals with the topic of slow extraction spill quality characterization based on the measurements performed at GSI SIS-18. The sensitivity of the spill to power supply ripples are studied by introducing external ripples. An estimate of sources of inherent power supply ripples along with ripple magnitude are thus obtained. Spill characterization in time and frequency domain are discussed and exemplified by a typical spill and the differences from an ideal or Poisson spill. An appropriate spill characterization aims to provide a suitable abstraction for communication about the spill quality requirements between accelerator operations and users., Published by IOP Publ., Bristol

HADES is a fixed target experiment using SIS18 heavy-ion beams. It investigates the microscopic properties of matter formed in heavy-ion, proton and pion - induced reactions in the 1-3.5 GeV/u energy regime. In 2014 HADES used a secondary pion beam produced by interaction between high-intensity nitrogen primary beam and a beryllium target. In these conditions beam losses, generated by slow extraction and beam transport to the experimental area, led to activation of the beam line elements and triggered radiation alarms. The primary beam intensity had to be reduced and the beam optics modified in order to keep radiation levels within the allowed limits. Similar beam conditions are requested by HADES experiment for upcoming run in 2018 and in the following years. Therefore, a number of measures have been proposed to improve beam transmission and quality. These measures are: additional shielding, additional beam instrumentation, modification of beam optics and increase of vacuum chambers' apertures in critical locations. The optics study and preliminary results of FLUKA simulations for optimization of location of loss detectors are presented., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark