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In recent research, the dynamics of the medium located in the seismic region at the boundary of tectonic plates is considered as the behavior of a complex open system that is in a state of self-organized criticality. Such an approach results from the very laws of earthquake generation and the complex structure of these areas. The network of faults and cracks makes seismic zones significantly heterogeneous and fragmented. Therefore, discrete models are increasingly used to model the dynamics of these media. The basis for comparing the model and the full-scale object serves the statistical regularities of their dynamic deformation. Relying on this concept, in the paper it is modeled the shear dynamics of a granular massif composed of identical cubic granules and is compared system’s statistical characteristics with the similar characteristics obtained for the earthquake generation zone. Shear deformation is carried out by means of the box consisting of two parts — movable and immovable ones. The movable part possesses the cover which receives kinetic energy from the granular massif in the process of shear deformation. For numerical simulations of the shear dynamics, the discrete element method is applied. The numerical calculations result in the distribution of cover’s kinetic energy jumps simulating the perturbations transmitted from the granular system to an external medium. It turned out that the distribution for these perturbations is the power dependence with an exponent that is inherent in earthquakes (Gutenberg-Richter law). Before and after large perturbations it is observed the swarms of smaller perturbations which are the analogues of foreshocks and aftershocks. The distributions of element’s velocity fluctuations and the correlation of velocity fluctuations are calculated as well. It is revealed the similarity of distributions for velocity fluctuations in the model massif and in the seismically active region of California, which includes the San Andreas fault. Moreover, the similarity of corresponding correlation functions is shown. They both are the functions of the stretched exponent. The obtained result indicates that shear processes in granular massifs and natural seismic processes in the San Andreas Fault are statistically similar.

It is known that soil massifs can amplify or weaken seismic waves generated by earthquakes. Therefore, the problem of studying the impact of soil deposits on the passage of seismic waves is important in terms of the facilities in operation and the design of new earthquake-resistant objects. Soil deposits, which are allotted for building, are mainly layered. In addition, the materials in these layers are also significantly heterogeneous. To describe the dynamics of inhomogeneous soil massif, the model of an elastic continuum with oscillating non-interacting inclusions is used. Within the framework of this model, the resonant properties of multi-layered soil deposit are analyzed at the conditions of harmonic perturbations applied to the bedrock. On the basis of the solution to the boundary value problem concerning oscillations of the system subjected to the free surface and conjugation conditions on the boundaries between layers, it is derived the transfer function which characterizes the amplification of shear displacements by the layered system. Within the framework of problems on the oscillations of two- and five layered systems, the analytical studies were confirmed by numerical evaluations of transfer functions. In particular, using the built-in functions of the system «Mathematica», it is developed the numerical procedure for evaluating the frequency dependencies of amplification factor for layered Kelvin—Voigt media and media with oscillating inclusions. Moreover, for the two-layered system, it is analyzed the effect on the transfer function for the ratio of layers’ shear moduli and the ratio of the inclusions’ natural frequencies. It is also shown that the maxima in the transfer function correspond to the eigenfrequencies of the boundary value problem.The obtained results and the proposed approach to the study of the response of the layered inhomogeneous medium to vibrational perturbations can serve as a theoretical basis for earthquake-resistant design and construction.

The approach to the study of the seismically active zone as an open system that is in a state of self-organized criticality is becoming increasingly used in modern research. The models used in this approach should reflect the most characteristic features of such media: discreteness, nonequilibrium, nonlinear and nonlocal nature of interactions. In this paper, the medium is modeled by a granular massif with ribbed grains. Three different massifs are used in the research. Within one massif, all grains are identical, while grains from different massifs differ in shape (cubic or irregular ribbed) and characteristic size. A number of experiments of shear deformation of such granular massifs were carried out in order to study the influence of the shape and size of grains on the statistical charac-teristics of the process. The influence of the stress state on the deformation properties of these media was also studied. The experiments proved the qualitative similarity of the behavior of different granular media. Obtained experimentally force jumps, represen-ting the reaction of the granular medium to shear deformation, obey the distributions in the form of power dependencies. However, the magnitudes of the forces arising in the massifs depend on the grain shape and size as well as the stress state in the massifs. The experiments with shear deformation of the granular media under the external action of small impulse stresses have shown that such action causes a smoother, devoid of sharp jumps, deformation. External perturbations shift the distribution of the force jumps towards smaller values, leaving their exponents unchanged. The analysis of experimental results using nonadditive statistical mechanics confirmed the presence of long-range correlations in the massif of ribbed granules during its shear deformation.

The article analyzes the functioning of the concept MODE in the modern German-speaking mass-media. The aim of this paper is to explore the peculiarities of the MODE concept in the German language by analysis of the specifics of the fashion vocabulary in the fashion magazines in particular Myself, Glamour, Petra, and Closer. The authors outline the group of lexical units that represent the MODE concept in German, analyze the synonymic series of the MODE lexeme and determine their dominants, suggest system of theme fields and groups of the fashion industry lexis. The linguistic means of verbalization of the MODE concept have been analyzed. The conducted research focuses on the basic models of word formation such as suffixation, word-composition, two-component and multi-component phrases. It has been established that one of the most common ways to replenish the fashion vocabulary are English and French borrowings.

The results of modern studies of the earthquakes impact indicate that the soil layers located under buildings and structures can significantly transform the seismic wave passing through their thickness and have a catastrophic effect on these objects. Hence, the study of wave processes in soil massifs is extremely important and relevant. It is known that soils are characterized by significant heterogeneity, which affects the spectral characteristics of seismic waves, so this should be taken into account when analyzing wave fields in the soil layers. In this paper, it is proposed to describe the dynamics of an inhomogeneous soil massif within the model of an elastic continuum with oscillating non-interacting dissipative inclusions. To examine vibrations in the layer of finite thickness with a free surface and harmonic perturbation applied to its lower edge, it is formulated the boundary value problem for the equations of medium’s motion. Based on the solution of this problem, the influence of inclusions on the characteristics of waves is analyzed. It is found out that the natural frequency of inclusions significantly affects the transfer function, which characterizes the amplification of the displacements on the free surface relative to the displacements at the lower boundary of the layer, i. e. when the natural frequency of inclusions increases, near the leading resonant peak additional resonant frequency appears, while for high frequencies a degeneration of resonant frequencies is observed. In the case when the natural frequencies of the inclusions have a non-discrete distribution with two separate frequencies, the effect of the inclusions is manifested at low-frequency oscillations, and in the high-frequency region only the resonant amplitude decreases. The approach, which uses the model with oscillating inclusions to the analysis of layer response to seismic disturbances, is promising for seismic design and construction., Результати сучасних досліджень наслідків землетрусів свідчать про те, що ґрунтові пласти, розташовані під будівлями та спорудами, можуть суттєво трансформувати сейсмічну хвилю, що проходить через їх товщу, та катастрофічним чином вплинути на ці об’єкти. Тому дослідження хвильових процесів у ґрунтових масивах є надзвичайно важливими і актуальними. Відомо, що ґрунти характеризуються значною неоднорідністю, яка впливає на спектральні характеристики сейсмічних хвиль, тому вона повинна враховуватись при аналізі хвильових полів у ґрунтових пластах. У цій праці запропоновано описувати динаміку неоднорідного ґрунтового масиву в рамках моделі пружного середовища з осцилюючими невзаємодіючими між собою дисипативними включеннями. Для такого модельного середовища ставиться крайова задача про вібрацію прошарку скінченної товщини з вільною поверхнею та гармонічним збуренням на його нижньому краї. На основі розв’язку цієї задачі проаналізовано вплив включень на характеристики хвиль. З’ясовано, що власні частоти включень суттєво впливають на передавальну функцію, яка характеризує підсилення зміщень на вільній поверхні відносно зміщень на нижній межі шару: при зростанні власної частоти коливань включень поблизу основного резонансу виділяється додаткова резонансна частота прошарку ґрунту, а на високих частотах відбувається виродження резонансів. Для випадку, коли власні частоти включень мають недискретний розподіл з двома виділеними частотами, вплив включень проявляється при низькочастотних коливаннях, а у високочастотному діапазоні зменшується лише резонансні амплітуди. Підхід до аналізу відгуку прошарку ґрунту на сейсмічні збурення, в якому використовується модель з коливними включеннями, є перспективним для задач сейсмостійкого проєктування та будівництва., Результаты современных исследований последствий землетрясений свидетельствуют о том, что грунтовые пласты, расположенные под зданиями и сооружениями, могут существенно трансформировать сейсмическую волну, проходящую через их толщу, и катастрофическим образом повлиять на эти объекты. Поэтому исследования волновых процессов в грунтовых массивах чрезвычайно важны и актуальны. Известно, что грунты обладают значительной неоднородностью, влияющей на спектральные характеристики сейсмических волн, поэтому она должна учитываться при анализе волновых полей в грунтовых пластах. В этой работе предложено описывать динамику неоднородного грунтового массива в рамках модели упругой среды с осциллирующими невзаимодействующими между собой диссипативными включениями. Для такой модельной среды становится краевая задача о вибрации слоя конечной толщины со свободной поверхностью и гармоническим возмущением на его нижнем крае. Опираясь на решение этой задачи, проанализировано влияние включений на характеристики волн. Выяснено, что собственные частоты включений существенно влияют на передаточную функцию, описывающую усиление смещений на свободной поверхности относительно смещений на нижней границе слоя: при увеличении собственной частоты колебаний включений вблизи основного резонанса выделяется дополнительная резонансная частота слоя грунта, а на высоких частотах происходит вырождение резонансов. Для случая, когда собственные частоты включений имеют недискретное распределение с двумя выделенными частотами, влияние включений проявляется при низкочастотных колебаниях, а в высокочастотной области уменьшаются только резонансные амплитуды. Подход к анализу реакции слоя грунта на сейсмические возмущения, в котором используется модель с колеблющимися включениями, является перспективным для задач сейсмостойкого проектирования и строительства.

An assessment of the resistance of self-pollinated corn lines to the action of the pathogen of bubble head in an infectious nursery with artificial infection of the onset. The result of the research was the isolation of the most tolerant to the damage of bubble head samples that will be used in breeding against resistance to this excitator (Ustilago zeae (Beckm.) Unger).

The paper deals with the model for a hierarchic multi-level medium. This model consists of the specifically coupled oscillators with power law interactions. We consider the periodic regimes appearing in the model when the uppermost structural level is driven by a harmonic force. To study these regimes as solutions of strongly nonlinear high-dimensional dynamical system, we improve the method of specific points (MSP) and verify the results via the Galerkin method and direct numerical treatment. This gives us the amplitude–frequency response curves characterizing the peculiarities of vibrations in the model. In particular, we revealed the shifting of resonant frequencies depending on the measure of nonlinearity. The deformations of backbone curves leading to jump phenomena are observed as well.

Мета: оцінити прихильність до довготривалого лікування хворих після інфаркту міокарда (ІМ) залежно від реваскуляризації.Матеріали і методи. Обстежено 152 хворих із інфарктом міокарда, яких поділено на групи: 1а – прихильні (за анкетуванням Morisky-Green), із перкутанним коронарним втручанням (ПКВ) (n=47), 1б – прихильні, без ПКВ (n=30); 2а – не прихильні, із ПКВ (n=25), 2б – не прихильні, без ПКВ (n=50). Оцінювали зміни клініко-лабораторних та ехокардіографічних значень.Результати. У всіх хворих не зменшувався індекс маси тіла, а 2/3 курять і досі. Серед осіб 1а групи, на відміну від решти груп, знижувались частота серцевих скорочень (ЧСС), систолічний та діастолічний артеріальний тиск (САТ та ДАТ), глюкоза та холестерол, і через 24 місяці зміни утримувались. Також у них достовірно змінювалась геометрія серця.Висновки. Після ІМ зберігається частковий комплаєнс. У цих пацієнтів встановлено дуже низьку прихильність до немедикаментозних методів вторинної профілактики та заходів із корекції факторів ризику і модифікації стилю життя, що зумовлює необхідність оптимізації організаційно-профілактичних заходів на амбулаторному етапі.

Dynamics of granular materials is a challenge for predictability of their response under dynamic load due to the complex behavior of granular systems. In this report, we consider the granular system composed of the polyhedral particles, namely cubes, and study system’s dynamics via the discrete element method which allows us to describe the interactions between cubes in detail. On the base of modeling the shear motion of granular medium, the statistical laws of multiparticle system dynamics are observed. These studies are extremely important for the geophysics, material science, etc.

Інфаркт міокарда (ІМ) є причиною високої смертності, інвалідизації та значних фінансових витрат в усіх країнах світу. В Україні щорічно реєструють до 50 тис. випадків ІМ, 50 % із цих пацієнтів помирають упродовж наступних 5 років. Тому оптимізація заходів вторинної профілактики (модифікація стилю життя, прихильність до подальшої медикаментозної терапії) має ключове значення у виживаності цих пацієнтів. Однак комплаєнсу при будь-яких захворюваннях вдається досягнути лише у 20–57 % випадків, і за даними літератури, стать має вплив на його рівень.Мета дослідження – багатофакторна оцінка прихильності жінок до лікування у післяінфарктний період.Матеріали і методи. Обстежено 408 жінок із гострим коронарним синдромом віком від 46 до 94 років (середній вік (71,30±0,44) року). Динаміку досліджуваних показників через 6; 12; 24 місяці вдалось простежити у 52 пацієнток. Відповідно до анкети Morisky–Green (D. E. Morisky, L. W. Green, 1986), виділено дві групи: перша (І) – прихильні 27 осіб – середній вік (65,26±0,44) року та друга (ІІ) – неприхильні 25 осіб – середній вік (68,52±1,88) року. Далі проведено аналіз та оцінку клініко-лабораторних та інструментальних показників.Результати досліджень та їх обговорення. В усіх жінок виявлено супутню патологію у поєднанні з артеріальною гіпертензією та цукровим діабетом 2 типу, надмірну масу тіла. Жінок першої групи швидше госпіталізували в стаціонар (через (15,37±4,9) год), ніж другої групи (через (6,45±18,9) год) з більшою часткою реваскуляризації – 28,8 % проти 5,7 %; більшою масою некрозу міокарда; вищими вихідними показниками систолічного (САТ) та діастолічного (ДАТ) артеріального тиску – (160±6,06) і (95,6±2,66) проти (153±6,11) і (89,4±2,37) мм рт. ст. та нижчим рівнем загального холестерину – (5,59±2,99) проти (6,46±2,77) ммоль/л. У динаміці в цій групі виявлялось достовірне зниження частота серцевих скорочень (ЧСС), СА Т та ДАТ та загального рівня холестерину та наближення показників ехокардіоскопії до притаманних для нормальної геометрії міокарда.Висновки. У жінок спостерігається недостатній рівень прихильності до наступної вторинної профілактики на амбулаторному етапі лікування і у більшості з них зберігається лише часткова прихильність, особливо через рік після перенесеного ІМ. Встановлено дуже низьку прихильність до немедикаментозних методів вторинної профілактики та заходів з корекції факторів ризику і модифікації стилю життя. Отримані результати ще раз вказують на необхідність оптимізації організаційно-профілактичних заходів на амбулаторному етапі. Можлива стратегія переходу в роботі з пацієнтами від “комплаєнсу до конкордансу” дозволить покращити вторинну профілактику інфаркту міокарда.

The myocardial infarction (MI) is the reason of high mortality, disability and significant financial charges all over the world. Every year in Ukraine more than 50 thousand incidences of MI, and 50 % of these patients dye for next 5 years. Thus, the optimization of secondary prevention arrangements (such as life style modification, the following medicine therapy adherence) has the key meaning in these patients’ survival. Thought the compliance in any diseases can be reached only in 20–57 % of incidences, and the literature affirms the sex influence on its level. The aim of the study – the multimentional evaluation of the women’s treatment adherence in post-infarction period. Materials and Methods. 408 women with acute coronary syndrome of 46–94 years (average age (71.30 ± 0.44) years) were observed. The dynamic of the examined indexes after 6, 12, and 24 months could be followed in 52 patients. 2 groups were established accordingly to Morisky-Greens’ application (Morisky D.E.,Green L.W., 1986): I (first) – 27 persons were adhered, the average age (65.26±0.44) year and the second (II) – unadhered 25 persons, the average age (68.52±1.88) year. The analysis and the estimation of the clinical, laboratory and instrumental indexes were provided. Results and Discussion. The comorbidity with arterial hypertension and diabetes mellitus type 2 and the overdue weight were detected in all observed women. Women from the group I were hospitalized earlier (within (15.37±4.9) hours) than in group II (in (6.45±18.9) hours) with bigger part of revascularization – 28.8% versus 5.7 % ; major myocardial necrosis mass; higher indexes of systolic and diastolic blood pressure (160±6.06) and (95.6±2.66) versus (153±6.11) and (89.4±2.37) mm Hg and lower cholesterol level – (5.59±2.99) versus (6.46±2.77) μmol/l. In dynamics the significant decreasing of the heart rate, systolic and diastolic blood pressure levels and the general cholesterol level were detected and the Echo-indexes approach to the proper normal myocardial geometry. Conclusions. Women’s insufficient adherence level to the following secondary prevention in ambulatory treating stage was observed and mostly only the partly adherence is steel preserved, especially in a year after the MI. Very low adherence to the non-pharmacologic secondary prevention methods and correction risk factors and life style modification arrangements were established. Received results once more assure on necessity of the organization and prevention optimization arrangements on the ambulatory stage. Possibly the regression strategy in patients qualification from “compliance to concordance” allows to advance the secondary MI prevention.

In this paper, the process of shear deformation of the medium formed by the cubic grains is investigated experimentally. It is demonstrated that the deformation process is intermittent and accompanied by the radiation of acoustic perturbations. These perturbations obey statistical laws that are inherent in natural seismic processes: the frequency-energy scaling relation (the Gutenberg-Richter law) and the generalized Omori law for temporal decay of aftershocks. The weak perturbations influence on the process of shear deformation is studied for the mono-dispersed medium. During the granular medium stimulation by weak periodic signals, the existence of a critical frequency providing the smallest number of critical events in the granular medium is identified. We also developed the algorithm providing smaller stresses inside the granular massif by means of external perturbations during shear deformation. Taking into account the statistical similarity between shear and seismic processes, these results open prospects for the ability to affect the natural seismic processes., Comment: 15 pages, 9 figures

The presented model for earthquakes is based on two fundamental principles: the hierarchical structure of seismic areas and the concept of self-organized criticality. The model reproduces the basic empirical properties of seismic processes: the frequency-energy scaling relation (the Gutenberg-Richter law), the generalized Omori law for temporal decay of aftershocks, the aftershock productivity law, the fractal distributions of hypocenters (epicenters) with power-law dependencies of the number of events on distances between hypocenters (epicenters), and, finally, the $\ensuremath{\gamma}$ distribution for waiting times. In the model, the threshold energies depend on the block sizes and are distributed according to the Gauss law. After strong earthquakes they are redistributed at the decreasing average values. The change of threshold energies leads to the triggering of aftershock series.

Force distribution in a granular medium subjected to an impulse loading is investigated in experiment and computer simulations. An experimental technique is developed to measure forces acting on individual grains at the bottom of the granular sample consisting of steel balls. Discrete element method simulation also is performed under conditions mimicking those in experiment. Both theory and experiment display exponentially decaying maximum force distributions at the bottom of the sample in the range of large forces. In addition, the simulations also reveal exponential force distribution throughout the sample and uncover correlation properties of the interparticle forces during dynamic loading of the granular samples. Simulated time dependence of coordination number, orientational order parameter, correlation radius, and force distribution clearly demonstrates the nonequilibrium character of the deformation process in a granular medium under impulse loading.

Computer simulation was performed to study compression wave propagation in a granular medium in a gravity field. It is shown that in a layer with spherical granules, periodic wave structures can be formed and their parameters depend on the granule size and layer thickness. If the layer is compressed, the wave structures fail to emerge and wave attenuation is much weaker. Wave processes in a layer of granular medium with nonspherical granules were also studied. It is shown that the medium is characterized by very strong wave attenuation and by the absence of wave structure formation and is highly sensitive to its initial stress state.

На сьогоднішній день доведено, що товщина комплексу інтима-медіа (КІМ) – важливий предиктор розвитку серцево-судинної та церебральної патології.

Suppression of non-resonant background due to emission of π0 increases signal to background ratio in γ-ray emission studies between the discrete states of charmonium. We demonstrate with Monte-Carlo simulations how π0 identification capability increases with decreasing threshold for γ-ray detection in π0 decay. An apparatus has been designed and measurements of the FWHM resolution performed for the three energies 6.13, 12.7 and 16.9 MeV. The trend established in the 50–650 MeV energy range is corroborated.

Identification of π 0 and η mesons by detecting both γ -rays from their decay is a prerequisite for suppressing undesired background in studies of photon transitions between the states of charmonium in the physics program of PANDA. To achieve this goal the detection threshold of the PANDA electromagnetic calorimeter (EMC) should be as low as possible. An experimental setup intended for measurements of the response of cooled PWO scintillators in the energy range 4.4–20 MeV has been designed and constructed. The setup uses γ -rays emitted in reactions induced by protons with light nuclei. Events with full-energy expended in PWO are selected by enclosing the studied 20 × 20 × 200 mm PWO-II scintillator in a cylinder of EJ-200 plastic scintillator, whose two halves are read out independently. A comparison of the relative Gaussian dispersions, σ / E , obtained by us for the three energies in the above energy range, indicates that a smooth dependence established at MAMI, for a matrix of 3 × 3 PWO-II scintillators between 40.9 and 674.5 MeV, also gives a valid extrapolation into the range of these very low energies.

Isotopic effects in projectile fragmentation at relativistic energies have been studied with the ALADIN forward spectrometer at SIS. Stable and radioactive Sn and La beams with an incident energy of 600 MeV per nucleon have been used in order to explore a wide range of isotopic compositions. Chemical freeze-out temperatures are found to be nearly invariant with respect to the A/Z ratio of the produced spectator sources, consistent with predictions for expanded systems. Consequences for the proposed interpretation of chemical breakup temperatures as representing the limiting temperatures predicted by microscopic models are discussed., Comment: 7 pages, 4 figures, contribution to proceedings of International School of Nuclear Physics, 30th Course, Heavy-Ion Collisions from the Coulomb Barrier to the Quark-Gluon Plasma, Erice-Sicily: 16 - 24 September 2008

A systematic study of isotopic effects in the break-up of projectile spectators at relativistic energies has been performed with the ALADiN spectrometer at the GSI laboratory. Searching for signals of criticality in the fragment production we have applied the model independent universal fluctuations theory already proposed to track criticality signals in multifragmentation to our data. The fluctuation of the largest fragment charge and of the asymmetry of the two and three largest fragments and their bimodal distribution have also been analysed., Comment: 6 pages, 4 figures, IX International Conference on Nucleus-Nucleus Collisions, Rio de Janeiro, Brazil, August 28 - September 1, 2006

Time-of-flight measurements in multifragmentation of heavy, relativistic projectiles require very good time resolution and at the same time the detecting system must cope with a dynamic range of up to 8000:1. We look into the possibility of application of large-area avalanche photodiodes (LAAPDs) as alternative light sensors to meet the above requirements. The paper presents the results of our amplitude and time response studies of a plastic scintillator BC-408 readout with a φ16 mm LAAPD using radioactive sources. The measurements were performed using two different setups. The best time resolution has been obtained by exploiting LAAPD cooling to increase its gain beyond that accessible at room temperature. We reach 610 ps (FWHM) at −26°C for the corresponding LAAPD gain of ≈900 and the 90 Sr / 90 Y β -ray source. We hope to reach below the desired 400 ps with the latter setup at the higher light levels available with multifragmentation products.

The article deals with the mathematical model for media with hierarchical structure. Using the hamiltonian formalism, the dynamical system describing the state of hierarchically connected structural elements was derived. According to the analysis of the Poincar\'e sections, we found the localized quasi-periodic and chaotic trajectories in the three-level hierarchical model. Moreover, studies of correlation functions shown that the power spectrum for three-level model possesses local maxima characterizing temporal scales with strong correlation. Using the Fourier analysis of the solution's components, we have studied the distribution of energy injected in the system over hierarchical levels. Dynamical phenomena in the multi-level system were studied as well., Comment: 12 pages, 8 figures

Experiments on deformation structured model medium formed by elements in the form of balls of the same diameter under the impulse loading are performed. It is found that the stress-strain diagram of such medium depends on the size of structure elements and the nature of their interaction. The character of deformation of the structured medium by multiple loads is investigated.

Maize parent material was assessed by the resistance of its root system to plucking. Highly productive hybrids created from this base were used to identify advanced hybrids that are most tolerant to infestation by western corn rootworm.

The performance of the LAND neutron detector is studied. Using an event-mixing technique based on one-neutron data obtained in the S107 experiment at the GSI laboratory, we test the efficiency of various analytic tools used to determine the multiplicity and kinematic properties of detected neutrons. A new algorithm developed recently for recognizing neutron showers from spectator decays in the ALADIN experiment S254 is described in detail. Its performance is assessed in comparison with other methods. The properties of the observed neutron events are used to estimate the detection efficiency of LAND in this experiment., 16 pages, 8 figures

The N/Z dependence of projectile fragmentation at relativistic energies has been studied with the ALADIN forward spectrometer at the GSI Schwerionen Synchrotron (SIS). Stable and radioactive Sn and La beams with an incident energy of 600 MeV per nucleon have been used in order to explore a wide range of isotopic compositions. For the interpretation of the data, calculations with the statistical multifragmentation model for a properly chosen ensemble of excited sources were performed. The parameters of the ensemble, representing the variety of excited spectator nuclei expected in a participant-spectator scenario, are determined empirically by searching for an optimum reproduction of the measured fragment-charge distributions and correlations. An overall very good agreement is obtained. The possible modification of the liquid-drop parameters of the fragment description in the hot freeze-out environment is studied, and a significant reduction of the symmetry-term coefficient is found necessary to reproduce the mean neutron-to-proton ratios /Z and the isoscaling parameters of Z, 23 pages, 29 figures, published in Physical Review C

A phase transition signature associated with cumulants of the largest fragment size distribution has been identified in statistical multifragmentation models and examined in analysis of the ALADIN S254 data on fragmentation of neutron-poor and neutron-rich projectiles. Characteristics of the transition point indicated by this signature are weakly dependent on the A/Z ratio of the fragmenting spectator source. In particular, chemical freeze-out temperatures are estimated within the range 5.9 to 6.5 MeV. The experimental results are well reproduced by the SMM model., 7 pages, 3 figures, Proceedings of the International Workshop on Multifragmentation and Related Topics (IWM2009), Catania, Italy, November 2009.

The A/Z dependence of projectile fragmentation at relativistic energies has been studied with the ALADIN forward spectrometer at SIS. A stable beam of 124Sn and radioactive beams of 124La and 107Sn at 600 MeV per nucleon have been used in order to explore a wide range of isotopic compositions. Chemical freeze-out temperatures are found to be nearly invariant with respect to the A/Z of the produced spectator sources, consistent with predictions for expanded systems. Small Coulomb effects (\Delta T \approx 0.6 MeV) appear for residue production near the onset of multifragmentation., Comment: 11 pages, 3 figures, accepted for publ. in Phys. Rev. Lett

R. BASSINI5), , C. BOIANO5), A.S. BOTVINA2), A. BOUDARD6), J. BRZYCHCZYK4), A. CHBIHI1), J. CIBOR8), B. CZECH8), J.-E. DUCRET6), H. EMLING2), J. FRANKLAND7), M. HELLSTROM2), D. HENZLOVA1), K. KEZZAR2), G. IMME1), I. IORI5), H. JOHANSSON2), A. LAFRIAKH3), , E. LE GENTIL6), Y. LEIFELS2) , W.G. LYNCH9), J. LUHNING2), , U. LYNEN2), Z. MAJKA4), M. MOCKO9), W.F.J. MULLER2), A. MYKULYAK10), H. ORTH2), A.N. OTTE2), R. PALIT2), P. PAW LOWSKI8) , A. PULLIA5), G. RACITI1), E. RAPISARDA1), H. SANN2), C. SCHWARZ2), H. SIMON2), K. SUMMERER2), M.B. TSANG9), C. VOLANT6), M. WALLACE9), H. WEICK2), J. WIECHULA2), A. WIELOCH4) and B. ZWIEGLINSKI10) 1) Dipartimento di Fisica, Universita degli studi di Catania and LNS-INFN, 64, Via S. Sofia, I-95123 Catania, Italy 2) Gesellschaft fur Schwerionenforchung, D-64291 Darmstadt, Germany 3) Institut de Physique Nucleaire, IN2P3-CNRS et Universite, F-91406 Orsay, France 4) M. Smoluchowski Institute of Physics, Jagiellonian Univ., Pl-30059 Krakow, Poland 5) Istituto di Scienze Fisiche, Universita degli Studi and INFN, I-20133 Milano, Italy 6) DAPNIA/SPhN, CEA/Saclay, F-91191 Gif-sur-Yvette, France 7) GANIL, CEA et IN2P3-CNRS, F-14076 Caen, France; 8) H. Niewodniczanski Institute of Nuclear Physics, Pl-31342 Krakow,Poland 9) Department of Physics and Astronomy and NSCL, MSU, East Lansing, MI 48824, USA; 10) A. So ltan Institute for Nuclear Studies, Pl-00681 Warsaw, Poland

The discriminant-analysis method has been applied to optimize the exotic-beam charge recognition in a projectile fragmentation experiment. The experiment was carried out at the GSI using the fragment separator (FRS) to produce and select the relativistic secondary beams, and the ALADIN setup to measure their fragmentation products following collisions with Sn target nuclei. The beams of neutron poor isotopes around 124La and 107Sn were selected to study the isospin dependence of the limiting temperature of heavy nuclei by comparing with results for stable 124Sn projectiles. A dedicated detector to measure the projectile charge upstream of the reaction target was not used, and alternative methods had to be developed. The presented method, based on the multivariate discriminant analysis, allowed to increase the efficacy of charge recognition up to about 90%, which was about 20% more than achieved with the simple scalar methods., Comment: 6 pages, 7 eps figures, elsart, submitted to Nucl. Instr. and Meth. A

A systematic study of isotopic effects in the break-up of projectile spectators at relativistic energies has been performed at the GSI laboratory with the ALADiN spectrometer coupled to the LAND neutron detector. Besides a primary beam of 124Sn, also secondary beams of 124La and 107Sn produced at the FRS fragment separator have been used in order to extend the range of isotopic compositions. The gross properties of projectile fragmentation are very similar for all the studied systems but specific isotopic effects have been observed in both neutron and charged particle production. The breakup temperatures obtained from the double ratios of isotopic yields have been extracted and compared with the limiting-temperature expectation., Comment: 10 pages, 5 figures, Proceeding of the XLV International Winter Meeting on Nuclear Physics, Bormio (Italy), 14-21 January 2007

Isotopic effects in projectile spectator fragmentation at 600 AMeV have been investigated using data collected in recent experiments with SIS beams at the GSI laboratory and with the ALADiN forward-spectrometer. For this purpose, primary beams of 124Sn, as well as secondary beams of 124La and 107Sn produced at the FRS fragment separator have been used. Isoscaling in 124,107Sn+Sn reactions is investigated and results are compared with data taken with the INDRA multidetector for 12C+112,124Sn reactions.

The N/Z dependence of projectile fragmentation at relativistic energies has been studied in a recent experiment at the GSI laboratory with the ALADiN forward spectrometer coupled to the LAND neutron detector. Besides a primary beam of 124Sn, also secondary beams of 124La and 107Sn delivered by the FRS fragment separator have been used in order to extend the range of isotopic compositions of the produced spectator sources. With the achieved mass resolution of \Delta A/A \approx 1.5%, lighter isotopes with atomic numbers Z \le 10 are individually resolved. The presently ongoing analyses of the measured isotope yields focus on isoscaling and its relation to the properties of hot fragments at freeze-out and on the derivation of chemical freeze-out temperatures which are found to be independent of the isotopic composition of the studied systems. The latter result is at variance with the predictions for limiting temperatures as obtained with finite-temperature Hartree-Fock calculations., Comment: 11 pages, 5 figures, Proceedings of International Workshop on Nuclear Dynamics in Heavy-Ion Reactions and Neutron Stars, Beijing, July 10-14, 2007, to appear in International Journal of Modern Physics E

PACS; Challenging motivations for isotopic studies in nuclear multifragmentation are derived from the the importance of the density dependence of the symmetry term of the nuclear equation of state for astrophysical applications and for effects linked to the manifestation of the nuclear liquid-gas phase transition. In a recent experiment with the ALADIN spectrometer at GSI, the possibility of using secondary beams for reaction studies at relativistic energies has been explored. Beams of $^{107}$Sn, $^{124}$Sn, $^{124}$La, and $^{197}$Au were used to investigate the mass and isospin dependence of multifragmentation. The status of the project and first results are reported and discussed.