The physics goals of the future Compressed Baryonic Matter (CBM) experiment (GSI/FAIR) are focused on the study of matter properties under conditions of extremely high baryon densities and moderate temperatures. The primary objective is the investigation of the phase diagram of quantum chromodynamics (QCD) in the region of high baryon densities. In particular, the study of the transition between hadronic matter and quark–gluon plasma, the search for the QCD critical endpoint and signatures of chiral symmetry restoration are planed. These studies are of fundamental importance for understanding the evolution of the early Universe. Such data are planned to be obtained through investigations of various processes, including charmonium production near threshold, fluctuations of baryon number, strangeness and electric charge, collective flow of hadrons, dilepton production, and strange particle production, among others. The CBM detector system is a forward spectrometer comprising a silicon tracking system, time-of-flight detectors, calorimeters, and muon detectors. The detector is designed to register reaction products from p–Au and Au–Au collisions in a fixed-target mode at energies up to 14 GeV and 29 GeV per nucleon for gold nuclei and protons, respectively, at interaction rates ranging from 1 MHz to 10 MHz. These operating conditions impose stringent constraints on the material budget and the placement of readout electronics, and require triggerless data acquisition (real-time readout and reconstruction), as well as minimisation of electronic noise to enable detection of weak and rare signals.
The dissertation is devoted to the study and development of electronic models of detector modules for the Silicon Tracking System (STS), as well as to the design of a prototype detector module for the proposed Radiation Monitoring System (RMS-CBM) of the future CBM experiment, to be implemented at the international research facility FAIR. The primary objective of this research is to establish efficient approaches for the modelling, analysis, and optimisation of the performance of STS detector modules, as well as to develop a prototype radiation monitoring system aimed at ensuring the stable operation of the experiment under conditions of high-intensity ion collisions.
Methods for describing complex electrical systems used in modern high-energy physics experiments are reviewed, with examples from existing models employed in experiments such as LHCb, ATLAS, CMS (CERN), and RHIC (Fermilab). Previous electronic models of STS detector modules and their components are also considered.
The original contribution of this work consists in the development of the first comprehensive electronic model of both the sensor and readout electronics of an STS detector module, reproducing the full chain of physical processes, as well as a model for the RMS-CBM detector module prototype.
The object of the research comprises silicon double-sided microstrip sensors, detector modules of the STS, and a prototype of the RMS-CBM radiation monitoring system. The subject of the research encompasses the physical processes occurring within the detector modules, in particular signal formation, charge transport, and the influence of noise and parasitic effects.
The study employs state-of-the-art numerical modelling techniques, including analogue electronics simulations using LTspice, Monte Carlo methods for modelling the interaction of ionizing radiation with the sensor material using Allpix2 and Geant4, as well as data analysis tools such as ROOT and Python.
