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New developments in arrays of Ge and Si detectors to observe prompt \(\gamma \)-ray and conversion electron emission at the target are described. To study the structure of nuclei lying far-from stability which are produced with sub \(\mu \)b cross-sections, the target arrays will be used in conjunction with recoil separators, employing the method of Recoil Decay Tagging. A new focal plane spectrometer, GREAT, will be constructed which will give increased sensitivity to the studies of rare nuclei either using the RDT technique for identification of the prompt emission or by recoil decay spectroscopy in the focal plane of the recoil separator.

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Recent results obtained by the INDRA collaboration concerning the physics of hot nuclei produced in intermediate energy heavy-ion collisions are presented.

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The principles for use of the \(\alpha \)-emitter \(^{211}\)At for tumour therapy are discussed. The use of \(\alpha \)-emitters instead of \(\beta \)-emitters for this purposes has the potential of providing a higher dose to the tumour with simultaneous lower dose to surrounding healthy tissue. Furthermore, \(\beta \)-active compounds with tumour affinity has a much higher efficiency the corresponding \(\beta \)-active compounds against single cell or micrometastatic cancer. Constraints and limitations of the method are discussed. Experiments with astatinated monoclonal antibodies as well as small molecules are described, as well as some possible strategies still not investigated.

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Digital spectroscopy is an experimental technique for directly processing of detector signals without analog signal shaping. Digital spectrometers capture the detailed shape of preamplifier signals with high speed ADCs, and then process captured waveforms in real time with field-programmable gate arrays and digital signal processors, that perform digitally all essential data processing functions, including precise energy measurement and event timing, ballistic deficit correction, pulse shape analysis, and time stamping the output data for offline analysis. Applications of this novel technology include position sensitive \(\gamma \)-ray spectroscopy with arrays of Ge detectors and high-speed particle emission spectroscopy. In both applications digital spectrometers process signals from semiconductor detectors in order to measure the interaction energy, time, and location within the detector volume. Excellent energy resolution and essentially zero dead time can be easily obtained with XIA digital spectrometer devices, even when time separation between consecutive events in a decay chain is shorter than \(1 \mu \)s. These and other applications of digital spectroscopy are at the frontier of experimental nuclear chemistry and nuclear physics.

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Radiotherapy with use of particle accelerators proceeds in many institutions in the world. Among them the HIMAC project is unique as the first medically dedicated heavy ion machine. The design, construction, characteristics and actual performance are described in detail.

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The paper raises the problem of the reconstruction quality of \(\pi ^0\) kinematics from the detection of both decay photons in a electromagnetic segmented calorimeter. The standard method of photon energy-scaling is compared with the kinematically-constrained fit procedure. The \(\chi ^2\) value from a fit to a given event was a subject of quantitative confidence level analysis. This analysis rejects only a negligible fraction of events in the case of the kinematic fit procedure, while a large fraction of events are discarded using the energy-scaling method. The width of the reconstructed pion energy distribution from the kinematic fit is reduced by 14% compared to the results of the energy scaling method. Applying the kinematical fit method to the experimental data, the reconstructed pion energy spectrum does not violate the kinematical limit imposed by the energy conservation, in contrast to the energy-scaling method.

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The WASA (Wide Angle Shower Apparatus) is a new detector system with very high acceptance presently being commisioned at the CELSIUS storage ring located at The Svedberg Laboratory in Uppsala. It has been designed to study rare decays of light mesons with sensitivity down to \(10^{-9}\) in the branching ratio. It will also allow for unprecedented quality measurements of differential cross sections of different reactions induced by protons and light nuclei.

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Dosimetric characteristics of 6 MeV circular X-ray beams of diameters ranging from 7.5 to 35.0 mm are reported. The 6-MeV X-ray beam from Clinac 2300CD was formed using additional cylindrical BrainLAB’s collimators. The mechanical stability of the entire system was verified. Specific quantities measured include tissue maximum ratios (TMR), beam profiles (off-axis ratios OAR) and relative output factors. Measurements of these parameters were performed in a water phantom using small cylindrical ionization chambers and a diamond detector. Comparison of TMR values measured with the ionization chamber and the diamond detector showed no significant differences. It was shown that the latter yields more accurate results for beam profiles than ionization chambers. The mechanical and dosimetric characteristics of this radiotherapy unit are found to be suitable for stereotactic radiosurgery and radiotherapy.

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In order to establish the optimal conditions of F\(^-\) ion production by the tubular ionizer extensive studies of SF6 ionization using the mass separator were performed. The SF6, SF5, SF4, SF3 and F negative ions were observed, and the F\(^-\) yields as a function of the source temperature, gas pressure and an amount of alkaline metal vapors (K, Na, Ca, Sr, Ba) were measured. The efficiency of F\(^-\) production of about 40obtained for the optimal conditions. The delay time and adsorption enthalpy of fluorine on the tantalum surface has been measured for the first time.

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The paper presents results of Monte Carlo modeling of an experimental Accelerator Driven System (ADS), which employs a subcritical assembly and a 660 MeV proton accelerator operating at the Laboratory of Nuclear Problems of the Joint Institute for Nuclear Research in Dubna. The mix of oxides (PuO\(_2\) + UO\(_2)\) MOX fuel designed for the reactor will be adopted for the core of the assembly. The present conceptual design of the experimental subcritical assembly in Dubna is based on the core with a nominal unit capacity of 30 kW (thermal). This corresponds to the multiplication coefficient \(k_{\rm eff}= 0.945\) and the accelerator beam power of 1 kW.

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We investigate the application of LSO and YSO scintillating crystals for Positron Emission Tomography (PET). Properties such as light output, energy resolution, detection efficiency for various energy threshold, and timing resolution are presented. These data allow us to evaluate the usage of finger-like LSO:Ce and YSO:Ce crystals coupled to photomultiplier tube, and to establish optimal operating conditions for high-resolution PET. Both crystals have advantages over BGO currently used in PET and LSO is considered as a possible replacement for BGO based systems.

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This paper describes principles of Accelerator-Driven Transmutation of Nuclear Wastes (ATW) and gives some flavour of the most important topics which are today under investigations in many countries. An assessment of the potential impact of ATW on a future of nuclear energy is also given. Nuclear reactors based on self-sustained fission reactions — after spectacular development in fifties and sixties, that resulted in deployment of over 400 power reactors — are wrestling today more with public acceptance than with irresolvable technological problems. In a whole spectrum of reasons which resulted in today’s opposition against nuclear power few of them are very relevant for the nuclear physics community and they arose from the fact that development of nuclear power had been handed over to the nuclear engineers and technicians with some generically unresolved problems, which should have been solved properly by nuclear scientists. In a certain degree of simplification one can say, that most of the problems originate from very specific features of a fission phenomenon: self-sustained chain reaction in fissile materials and very strong radioactivity of fission products and very long half-life of some of the fission and activation products. And just this enormous concentration of radioactive fission products in the reactor core is the main problem of managing nuclear reactors: it requires unconditional guarantee for the reactor core integrity in order to avoid radioactive contamination of the environment; it creates problems to handle decay heat in the reactor core and finally it makes handling and/or disposal of spent fuel almost a philosophical issue, due to unimaginable long time scales of radioactive decay of some isotopes. A lot can be done to improve the design of conventional nuclear reactors (like Light Water Reactors); new, better reactors can be designed but it seems today very improbable to expect any radical change in the public perception of conventional nuclear power. In this context a lot of hopes and expectations have been expressed for novel systems called Accelerator-Driven Systems, Accelerator-Driven Transmutation of Waste or just Hybrid Reactors. All these names are used for description of the same nuclear system combining a powerful particle accelerator with a subcritical reactor. A careful analysis of possible environmental impact of ATW together with limitation of this technology is presented also in this paper.

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Accelerator Mass Spectrometry (AMS) is an ultra sensitive method for the measurement of isotope ratios in the range of 10\(^{-12}\) to 10\(^{-15}\). Most frequently the \(^{14}\)C/\(^{12}\)C ratio from biogenic samples is determined which gives information on the age of the sample of up to 40 ka with a precision of typically 40–80 years. In this paper the radiocarbon method is discussed and various applications to interdisciplinary research are presented. A main application at the Erlangen AMS facility is the \(^{14}\)C dating of sediment samples which together with simultaneous pollen analyses can establish a better chronology of climate and vegetation during Holocene in Germany. For an enhanced reliability of sediment dating different fractions like bulk sediments, pollen grains, macrofossiles and humic acids have been measured. For environmental research the \(^{14}\)C content of volatile chlorinated hydrocarbons can be used to disentangle the anthropogenic or biogenic origin of these compounds. Finally an interesting archaeological sample is discussed.

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The FOPI detector system has been built to study the properties of dense and hot nuclear matter with the beam (0.1–2 GeV/nucleon) of the heavy ion synchrotron SIS at GSI Darmstadt. A modular system covering nearly the full 4\(\pi \) solid angle has been assembled in stages between 1990 and 1995, having already been used since 1991 in various experiments employing its expanding capabilities. Since the first phase of experiments, when nucleons and intermediate mass fragments could be detected at projectile- and midrapidity, FOPI developed into a specialized system detecting also pions, kaons, antikaons and identifying signals from decays of neutral particles with a strange quark content like \({\mit \Lambda }\), \({\mit \Phi }\) and \(K_{\rm S}^0\). Studies of strangeness production and propagation became an important new line of the FOPI research programme. In order to extend the strangeness research and include kaon studies in heaviest systems an upgrade program for the FOPI detector system has been started. It aims at broadening the phase space of \(K^{+}\) and \(K^{-}\) identification and at extending the efficiency as well as selectivity of data collecting. The upgrade of the subdetectors mainly involves the modification of TOF detectors by replacing a part of the scintillator layer with Pestov spark counters. New experiments are expected to begin in 2001. The capabilities of the FOPI system are illustrated by examples of recent and earlier results.