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Ions injected into a multipole RF trap (where they are neutralized in charge-exchange reactions) are proposed to be used to determine the energy of electrons from the decay of the 229Th isomer. A conversion electron is emitted within a few microseconds after neutralization. A deceleration spectrometer with magnetic collimation coupled with the ion trap is planned to be used to determine the electron energy. The spectrometer’s design and the results from modeling are discussed.

The method of gas transport of fission products from a target chamber positioned near the core of a research reactor to the measurement apparatus located outside the physical protection is studied. The aim was to optimize this method for the PIK high-flux reactor, which is in the start-up stage. The obtained parameters – efficiency of product collection from the target, rate of transport of the gas jet, optimal characteristics of a capillary system, and others – can be helpful for developing systems for real-time production of short-lived nuclides in high-flux reactors.

The design and expected characteristics of an experimental setup for generating a beam of singly, doubly, and triply charged ions of 229mTh isomer are considered. The scheme of ion transport, the preparation of the thin source, and the means of registering low-energy conversion electrons are described.

A plan for using Penning ion traps to solve fundamental physical problems is presented. Placed in the secondary beam from the high-flux PIK reactor they can be used for direct high-precision measurements of the mass of exotic nuclides participating in different nuclear and astrophysical processes, some of which can be difficult to achieve in other currently existing facilities. Traps used in an autonomous regime outside a beam will make it possible to perform measurements with long-lived and stable nuclei for atomic, nuclei, and neutron physics as well as other areas of science.

A new way to bring into comparison the binary- and ternary-fission configurations is proposed. The method is founded on recently discovered ROT effect. The angle of fission axis deflection from its initial orientation at the moment of scission comes into existence as a result of dividing system rotation and carries information about fissioning nucleus deformation. The comparison of proper angles for binary and ternary fission can be used to estimate the difference in the rupture configurations.

With the Penning-trap mass spectrometer SHIPTRAP at GSI, Darmstadt, it is possible to investigate exotic nuclei in the region of the heaviest elements. Few years ago, challenging experiments led to the direct measurements of the masses of neutron-deficient isotopes with Z = 102,103 around N = 152. Thanks to recent advances in cooling and ion-manipulation techniques, a major technical upgrade of the setup has been recently accomplished to boost its efficiency. At present, the gap to reach more rare and shorter-lived species at the limits of the nuclear landscape has been narrowed. ispartof: pages:423-429 ispartof: Acta Physica Polonica B vol:48 issue:3 pages:423-429 ispartof: location:Zakopane: POLAND status: published

A shift of the angular distribution of α particles accompanying the 235U(n, f) reaction induced by cold polarized neutrons is determined for the first time on the basis of modified trajectory calculations taking into account prescission rotation of the compound nucleus, which causes this shift. The results of the calculations are in very good agreement with the experimental data of [1], where this new phenomenon was called the ROT effect.

The urgent problem of reducing energy outlays for the granulation of free-flowing materials by nodulization, for example, fertilizers, by eliminating excessive recycling of the process due to screening of conditioned granules corresponding to the marketable fraction, is discussed. A diagram is presented for an experimental device — inclined compartmented box. An example of determination of the required length of the compartments, and their number is given.

The MATS project for research on short-lived nuclides using ion traps is described. The physical program is aimed at performing nuclear-physical and astrophysical research using exotic nuclei which are near their boundaries of nucleonic stability. The project is devoted to precision measurements of the masses (total binding energy) and spectroscopic characteristics of ideally separated nuclides in traps. The development of novel methods will also make it possible to develop the applied components of the project.

Nuclear ground state properties including mass, charge radii, spins and moments can be determined by applying atomic physics techniques such as Penning-trap based mass spectrometry and laser spectroscopy. The MATS and LaSpec setups at the low-energy beamline at FAIR will allow us to extend the knowledge of these properties further into the region far from stability. The mass and its inherent connection with the nuclear binding energy is a fundamental property of a nuclide, a unique “fingerprint”. Thus, precise mass values are important for a variety of applications, ranging from nuclear-structure studies like the investigation of shell closures and the onset of deformation, tests of nuclear mass models and mass formulas, to tests of the weak interaction and of the Standard Model. The required relative accuracy ranges from 10−5 to below 10−8 for radionuclides, which most often have half-lives well below 1 s. Substantial progress in Penning trap mass spectrometry has made this method a prime choice for precision measurements on rare isotopes. The technique has the potential to provide high accuracy and sensitivity even for very short-lived nuclides. Furthermore, ion traps can be used for precision decay studies and offer advantages over existing methods. With MATS (Precision Measurements of very short-lived nuclei using an A_dvanced Trapping System for highly-charged ions) at FAIR we aim to apply several techniques to very short-lived radionuclides: High-accuracy mass measurements, in-trap conversion electron and alpha spectroscopy, and trap-assisted spectroscopy. The experimental setup of MATS is a unique combination of an electron beam ion trap for charge breeding, ion traps for beam preparation, and a high-precision Penning trap system for mass measurements and decay studies. For the mass measurements, MATS offers both a high accuracy and a high sensitivity. A relative mass uncertainty of 10−9 can be reached by employing highly-charged ions and a non-destructive Fourier-Transform Ion-Cyclotron-Resonance (FT-ICR) detection technique on single stored ions. This accuracy limit is important for fundamental interaction tests, but also allows for the study of the fine structure of the nuclear mass surface with unprecedented accuracy, whenever required. The use of the FT-ICR technique provides true single ion sensitivity. This is essential to access isotopes that are produced with minimum rates which are very often the most interesting ones. Instead of pushing for highest accuracy, the high charge state of the ions can also be used to reduce the storage time of the ions, hence making measurements on even shorter-lived isotopes possible. Decay studies in ion traps will become possible with MATS. Novel spectroscopic tools for in-trap high-resolution conversion-electron and charged-particle spectroscopy from carrier-free sources will be developed, aiming e.g. at the measurements of quadrupole moments and E0 strengths. With the possibility of both high-accuracy mass measurements of the shortest-lived isotopes and decay studies, the high sensitivity and accuracy potential of MATS is ideally suited for the study of very exotic nuclides that will only be produced at the FAIR facility.Laser spectroscopy of radioactive isotopes and isomers is an efficient and model-independent approach for the determination of nuclear ground and isomeric state properties. Hyperfine structures and isotope shifts in electronic transitions exhibit readily accessible information on the nuclear spin, magnetic dipole and electric quadrupole moments as well as root-mean-square charge radii. The dependencies of the hyperfine splitting and isotope shift on the nuclear moments and mean square nuclear charge radii are well known and the theoretical framework for the extraction of nuclear parameters is well established. These extracted parameters provide fundamental information on the structure of nuclei at the limits of stability. Vital information on both bulk and valence nuclear properties are derived and an exceptional sensitivity to changes in nuclear deformation is achieved. Laser spectroscopy provides the only mechanism for such studies in exotic systems and uniquely facilitates these studies in a model-independent manner.The accuracy of laser-spectroscopic-determined nuclear properties is very high. Requirements concerning production rates are moderate; collinear spectroscopy has been performed with production rates as few as 100 ions per second and laser-desorption resonance ionization mass spectroscopy (combined with β-delayed neutron detection) has been achieved with rates of only a few atoms per second.This Technical Design Report describes a new Penning trap mass spectrometry setup as well as a number of complementary experimental devices for laser spectroscopy, which will provide a complete system with respect to the physics and isotopes that can be studied. Since MATS and LaSpec require high-quality low-energy beams, the two collaborations have a common beamline to stop the radioactive beam of in-flight produced isotopes and prepare them in a suitable way for transfer to the MATS and LaSpec setups, respectively., This manuscript has been acomplished by the contributions from several members of the MATS and LaSpec collaborations. All the contributions are acknowledged and without them this document would not exist. We also acknowledge support from the Max-Planck Society as well as from several funding agencies in Spain which provided economical support for the organization of the 3rd LaSpec-MATS collaboration meeting held in Matalascañas (Huelva) in October 2008. This meeting served to fix the TDR contents. These funding agencies are Junta de Andalucía and CPAN (Centro Nacional de Partículas Astropartículas y Nuclear).

1. The width of the wound tape and the “degree” of interweaving of the tapes have no effect on the elastic characteristics of the glass fiber-reinforced epoxy wound plastic with the reinforcement angle ±45°. 2. The increase of the reinforcement factor increases the elasticity modulus whose value may be calculated with sufficient accuracy by the methods of the structural theory of composites. 3. The width of the wound tape influences the strength of the composite; the reduction of the width of the tape increases strength. 4. An increase of the “degree” of interweaving of the tapes reduces the strength in axial tensile loading; the zones of interweaving represent the “weak member” of the composite. 5. The variation of the reinforcement factor in the examined range has a strong effect on the strength of the composite. This is associated with the variation of the thickness of the interlayer of the binder between the wound tapes.

The design of drum type granulators consists of selecting the optimum dimensions of the drum and its operating conditions, which will yield the desi red granule size and specified quality, and the des i red capacity. The purpose of the work ca r r i ed out in MIKhM was to establish the relationship between the granule path length and capacity, and the dimensions of the drum, the extent to which it is filled, angular velocity of rotation, and the angle of incline.