Detection of highly ionizing particles: Nonlinear near-surface phenomena in silicon radiation detectors

• Published in: Physics of particles and nuclei Vol. 44; no. 1; pp. 92 - 114
• Main Author: Tsyganov, Yu. S.
• Format: Journal Article
• Language: English
• Published: Dordrecht SP MAIK Nauka/Interperiodica 01.01.2013
• Subjects: CROSS SECTIONS; HEAVY IONS; HEAVY NUCLEI; INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; ION BEAMS; NONLINEAR PROBLEMS; Particle and Nuclear Physics; PARTICLES; Physics; Physics and Astronomy; PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; SI SEMICONDUCTOR DETECTORS; SILICON; THERMONUCLEAR REACTIONS; Method Phys; Silicon Detector; Recoil Nucleus; Fission Fragment; Superheavy Nucleus
• ISSN: 1063-7796; 1531-8559
• DOI: 10.1134/S1063779613010061

As far as the detection system is concerned, experimens on synthesis and study of the properties of superheavy nuclei is one of the most difficult tasks. In fact, these experiments can be considered extreme in many senses: —extremely low (fractions of a picobarn-picobarns) formation cross sections of the products under investigation —extremely high heavy ion beam intensities for example, ∼1.1–1.5 pμA 1 48 Ca —high radioactivity of actinide targets, which are used in the experiments aimed at the synthesis of super-heavy nuclei —very long duration of the experiment (as long as a year) —extremely low yield of the products under investigation (sometimes less than 1 per month) —very high sensitivity of the detection system —radical suppression of the background products (method of “active correlations”). The two last points are the subject of the present paper, as well as the subject of two of my reviews published before. It is evident that without knowledge of the nature of the internal processes in semiconductor detectors it is virtually impossible to provide clear detection of ultra rare signals. In the present paper, the author reports on the investigation of near-surface phenomena in silicon radiation detectors, first of all bearing in mind the theoretical-methodological aspect of these phenomena. Non-equilibrium electron-hole recombination, pulse height defect formation, charge multiplication, and formation of “hot” electron system, are considered. With just these phenomena one can observe nonlinearity of energy-charge-amplitude conversion for heavy ion (recoil nucleus) registered by a silicon detector. Practical applications are also considered. One of them is a deeply modified method of “active correlations”. Projection of applying the method in the experiments with the modernized cyclotron (DC-280 FLNR project) is projected as well as possible applications in the heavy-ion-induced complete fusion nuclear reactions.