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In recent years, a single ion hit facility has been constructed at the IFJ ion microprobe. The setup is used for the precise irradiations of living cells by a controlled number of ions. Investigations of such type have two very important requirements: (1) cells must be examined in their natural state and environment (i.e. without previously being killed, preferentially neither fixed nor stained) and (2) the possibility of automatic irradiation of large number of cells (including computer recognition of cells positions) must be provided. This work presents some of the crucial features of the off-line and on-line optical systems, including self-developed software responsible for automatic cell recognition. [ABSTRACT FROM PUBLISHER]

Recently, the Cracow ion microprobe has found its new application as a single ion hit facility (SIHF), allowing precise irradiations of living cells by a controlled number of ions. The instrument enables a broad field of research, such as survival studies, adaptive response investigations, bystander effect, inverse dose-rate effect, low-dose hypersensitivity, etc. This work presents principles of construction and operation of the SIHF based on the Cracow microprobe. We discuss some crucial features of optical, positioning, and blanking systems, including self-developed software responsible for semiautomatic cell recognition, for precise positioning of cells, and for controlling the irradiation process. We also show some tests carried out to determine the efficiency of the whole system and of its segments. In addition, we present results of the first irradiation measurements performed with living cells. [ABSTRACT FROM AUTHOR]

Abstract: The Cracow single ion hit facility (SIH) is using the Van de Graaff-based microprobe with current spatial resolution of about 10μm in vacuum. Living cells are irradiated with the exact number of 2MeV protons. This work shows the present setup and test measurements optimizing the detection of single protons, beam deflection after registering single proton and the accuracy of cell targeting as well as the description of performance of the whole setup. The article presents also ways of cells visualisation and positioning during a single measurement and reports on first experiments with living cells carried out at the new facility. [Copyright &y& Elsevier]