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In the course of a round table with international participation organized by the Department of Comparative Political Science of Lomonosov Moscow State University and the electronic journal “Bulletin of Moscow State Regional University”, a discussion was held on the mobilization mechanisms of states (Russia, China, India, Canada, Great Britain, Kazakhstan, etc.) in countering the COVID-19 pandemic. The main topics of discussion include the following: state mobilization mechanisms in the situation of the first and subsequent waves of the COVID-19 pandemic, interaction between citizens and authorities, the perception of the population of anti-epidemic measures of governments, changes occurring under the influence of the pandemic in the social, economic, political spheres of society, in the areas of digitalization and education, forecasting the progress of the fight against the pandemic. The experts at the round table were political scientists of the Lomonosov Moscow State University, National Autonomous University of Mexico (Mexico City, Mexico), Al-Farabi Kazakh National University (Almaty, Kazakhstan), universities of the People’s Republic of China.

Nuclear instruments & methods in physics research / B 504, 33 - 42 (2021). doi:10.1016/j.nimb.2021.07.015, Published by Elsevier, Amsterdam [u.a.]

Matter and radiation at extremes 4(5), 055403 (2019). doi:10.1063/1.5097035, Published by Elsevier, Amsterdam

Aim. Evaluation of markers of systemic inflammation in patients with chronic heart failure in comorbidity with chronic kidney disease.Methods. The study included 188 patients with heart failure and kidney disease including control group (76 patients) with heart failure with preserved renal function aged 38 to 83 years (mean age 66.8±10.1 years), with the duration of heart failure of about 8 years. Quantitative measurement of C-reactive protein and proteins of blood serum and daily excretion of protein with urine were performed.Results. Glomerular filtration rate in patients without renal pathology was 71.1±11.7 ml/min/1.73 m2, and in the group with heart failure associated with kidney dysfunction it was 51.5±19.1 ml/min/1.73 m2. C-reactive protein, γ-globulin, albumin and total serum protein in patients with chronic kidney disease differed from those in patients with heart failure without kidney damage.Conclusion. C-reactive protein and γ-globulin in the serum significantly increase in patients with heart failure and chronic kidney disease and can be used as markers of cardiac as well as renal events.

Activation data for an aluminum target irradiated by 200 MeV/u 238 U ion beam are presented in the paper. The target was irradiated in the stacked-foil geometry and analyzed using gamma-ray spectroscopy. The purpose of the experiment was to study the role of primary particles, projectile fragments, and target fragments in the activation process using the depth profiling of residual activity. The study brought information on which particles contribute dominantly to the target activation. The experimental data were compared with the Monte Carlo simulations by the FLUKA 2011.2c.0 code. This study is a part of a research program devoted to activation of accelerator construction materials by high-energy (⩾200 MeV/u) heavy ions at GSI Darmstadt. The experimental data are needed to validate the computer codes used for simulation of interaction of swift heavy ions with matter.

Some soft magnetic metallic glasses are considered for use in magnetic cores of accelerator radio frequency cavities. Due to losses of the circulating ion beam, they may be exposed to irradiation by different ions at different energies. This paper presents data and review results of irradiation experiments concerning the influence of high-energy heavy ions on magnetic susceptibility of VITROPERM®-type metallic glasses. Samples of the VITROPERM® magnetic ribbons were irradiated by Au, Xe and U ions at 11.1 MeV/A (per nucleon) and 5.9 MeV/A, respectively. Irradiation fluences from 1 × 1011 up to 1 × 1013 ions/cm2 were applied. In case of the Au and U ions, the total fluence was accumulated in one beamtime, whereas two separate beamtimes were used to accumulate the final fluence in case of the Xe ions. Relative change in the samples’ magnetic susceptibility after and before irradiation was evaluated as a function of the irradiation fluence. The irradiation experiments were performed with the UNILAC accelerat...

Beam loss monitoring is an important aspect of proper accelerator functioning. There is a variety of existing solutions, but each has its own disadvantages, e.g. unsuitable dynamic range or time resolution, high cost, or short lifetime. Therefore, new options are looked for. This paper shows a method of application of a charge-coupled device (CCD) video camera as a beam loss monitor (BLM) for ion beam accelerators. The system was tested with a 500 MeV/u N+7 ion beam interacting with an aluminum target. The algorithms of camera signal processing with LabView based code and beam loss measurement are explained. Limits of applicability of this monitor system are discussed.

The breakdown voltage of radiation damaged polyimide is investigated. Motivated by the application of polyimide as insulator used in ion accelerator magnets of the future Facility for Antiproton and Ion Research (FAIR), two different kinds of polyimides were irradiated with different high energetic ion beams (p, C, Ni, Ru and Au) and with gamma radiation from a Co-60 source. Breakdown voltage measurements showed that the dielectric strength of irradiated polyimide was found to decrease as a function of the irradiation dose. The rate of decrease was found to be dependent on i) the type of radiation and ii) the angle of incident beam. Gamma and proton radiation leads only to minor changes in the observed dose regime while heavy ion irradiation drastically decreases the dielectric strength at even low doses. For heavy ion irradiation the rate of decrease is found to be dependent on the energy loss of the used particle beams. Furthermore an increase in incident beam angle, i.e. closer to the surface normal gives a lower decrease in the dielectric strength suggesting that the breakdown follows the path length of the produced ion tracks. Weibull analysis was used on a selected data set to discuss failure expectations for the later FAIR magnets.

The paper presents the results of irradiation of aluminum targets by 430 and 500 MeV/u argon beams. Gamma-spectra were measured after the end of the irradiation in order to identify the induced nuclides as well as to determine their residual activity depth-profiles. The results of this experiment are compared with Monte Carlo simulations by FLUKA, GEANT4, MARS, PHITS and SHIELD-A codes. In case of a thin target, the agreement between the experiment and simulations is satisfactory, while in case of a thick target, some discrepancies are observed.

The paper presents new experimental results and FLUKA-simulations of residual activation induced by high-energy argon ions in copper. It follows the previous residual activation studies performed at GSI Helmholtzzentrum fur Schwerionenforschung in Darmstadt with uranium ions as a preparatory work for constructing the FAIR facility. Copper samples were irradiated by 1 GeV/u and 500 MeV/u 40Ar ions and investigated by gamma-ray spectroscopy. The samples were irradiated in the stacked-foil geometry. The isotopes with dominating contribution to the total residual activity were identified and their partial activities were quantified. Depth-profiling of the partial residual activities of all identified isotopes was performed by measurements of individual target foils. The experimental results were compared with simulations by the FLUKA-code. A satisfactory agreement between the experiment and the simulations was observed.

The activation of structures and surroundings of new high-intensity heavy-ion accelerators like the Facility for Antiproton and Ion Research (FAIR) is an important issue. Monte Carlo codes such as FLUKA allow the prediction of the production of individual radioactive isotopes and the induced radioactivity that causes the main contribution to the radiation exposure of personnel. The work is a benchmark study of activation predictions for uranium beams with 500 and 950 MeV/u deposited in copper and stainless steel targets. Precise gamma spectrometry measurements for isotope identification have been carried out with a HPGe detector. All gamma-emitting radionuclides with half-lives ofmore than 2 days that contribute significantly to the residual dose rates have been studied. The benchmark study shows that FLUKA is a suitable code for the prediction of induced radioactivity at medium-energy heavy-ion accelerators.

The paper reviews the activities and reports the current results of GSI-INTAS projects that are dealing with investigations of construction materials for high-power accelerators and their components. Three types of materials have been investigated, namely metals (stainless steel and copper), metallic glasses (Nanoperm, Finemet and Vitrovac) and organic materials (polyimide insulators and glass fiber reinforced plastics/GFRP). The materials were irradiated by different ion beams with various fluencies and energies. The influence of radiation on selected physical properties of these materials has been investigated with the aid of gamma-ray spectroscopy, transmission Mossbauer spectroscopy (TMS), conversion electrons Mossbauer spectroscopy (CEMS), optical spectroscopy (IR and UV/VIS) and other analytical methods. Some experiments were accompanied with computer simulations by FLUKA, SHIELD and SRIM codes. Validity of the codes was verified by comparison of the simulation results with experiments. After the va...

As a preparatory work for constructing the FAIR facility at GSI, samples of stainless steel and copper were irradiated by 950 MeV/u 238U ions and depth-profiles of residual activity were measured by gamma-ray spectroscopy. The isotopes with dominating contribution to the residual activity were identified and their contributions were quantified. In contrast to the previous study performed at lower energies, the activities could no longer be determined from the full-assembly target measurements. Depth-profiling of residual activity of all identified isotopes had to be completed by measurements of individual target foils. The activity contributions were then obtained by integration of the depth-profiles.

The paper presents the results of precision measurements of the total stopping range and energy deposition function of 238U ions with specific energies E = 500 and 950 MeV/u in stainless steel and copper targets. The experiment was performed at the SIS-18 facility (GSI Darmstadt) in the experimental area Cave A in September 2004–May 2005. The measured energy deposition profiles are compared with calculations using the codes ATIMA, PHITS, SHIELD and SRIM.

First results of an experimental study of the residual activity induced by high-energy uranium ions are presented. As a preparatory work for constructing the FAIR facility at GSI, samples of stainless steel and copper were irradiated by 500 MeV/u 238 U ions and investigated by gamma-ray spectroscopy. The isotopes that contribute dominantly to the residual activity have been identified and their contributions have been quantified. Depth-profiles of residual activity of individual isotopes have shown that target activation due to projectile fragments and neutrons extends far beyond the range of primary particles and reaches the same level as in the region irradiated by primary particles.

The FAIR project planned at G.S.I. (Germany) requires the construction of several superconducting accelerator rings. One of the two synchrotron rings, named SIS300, will have dipoles with a central field of 6 T and a ramp rate of 1 T/s. In order to protect these fast-ramping magnets in case of a quench, each of them must be equipped with a diode stack that bypasses the magnet in case it quenches. In order to save time and money on R&D, we decided to use the same diode type as that mounted in LHC magnets. These diodes were previously tested at 77 K up to a fast neutron fluence (F) of 2.8E13 n/cm2 and a dose (D) of 2 kGy which are the expected radiation loads after 20 years of LHC operation. Having no definitive estimation of the losses in the SIS300, we arbitrarily targeted a fluence of 1E14 n/cm2. We irradiated six LHC type diodes at 77 K in six steps. The highest values measured were 1.31 kGy and 2.25E14 n/cm2. Before and after each irradiation step, the forward and reverse voltage characteristics of each diode were measured. This paper reports the results of these measurements, carried out at ITEP (Moscow).

A theoretical model to describe the vacuum instability induced by the lost particles in heavy-ion accelerators is proposed and applied to the U+28 beam lifetime measurements in the SIS18 at GSI, where the instability is of concern for high-intensity operation. The method allows to derive values of the desorption yield, the charge-exchange cross-section and the total pumping speed from the measurements of the beam lifetime I(t). The obtained desorption yields are comparable with those found in the other heavy-ion machines. Directions of possible cures are discussed.

High-energy protons bombarding matter are stopped mostly by inelastic collisions with the target nuclei, inducing a high level ofradio-activation. In contrary, it is shown here that the penetration depth ofheavy ions with energy below 1 GeV=u is mostly determined by the electronic stopping power. This results in lower activation levels, which is important for estimating the tolerable beam loss limit in high intensity heavy ion accelerators. A method to calculate the total neutron yield ofheavy ions bombarding thick targets is proposed, validated by measured data and applied to the tolerable beam loss limit in heavy ion accelerators in the energy range E ¼ 100 MeV=u–1 GeV=u: r 2003 Elsevier Science B.V. All rights reserved. PACS: 29.20.D; 34.50.B; 61.85; 25.75; 87.50.N; 87.50.P

While beam loss issues have hardly been considered in detail for heavy ion fusion scenarios, recent heavy ion machine developments in different labs (European Organization for Nuclear Research(CERN), Gesellschaft für Schwerionenforschung (GSI), Institute for Theoretical and Experimental Physics (ITEP), Relativistic Heavy-Ion Collider (RHIC)) have shown the great importance of beam current limitations due to ion losses. Two aspects of beam losses in heavy ion accelerators are theoretically considered: (1) secondary neutron production due to lost ions, and (2) vacuum pressure instability due to charge exchange losses. Calculations are compared and found to be in good agreement with measured data. The application to a Heavy-Ion Driven Inertial Fusion (HIDIF) scenario is discussed.

Accumulation of ions in a storage ring using charge exchange injection gives the possibility of storing the ion beam with parameters applicable to plasma experiments. Beam quality on the target can be defined by the factor of beam quality K b =1.5 Pa , where P is specific power, and a is beam radius. A simple formula, which allows one to estimate the value of K b for arbitrary accelerator parameters, is derived. This formula shows that in the absence of an electron cooling system (ECS) the main limitations appear due to intra beam scattering, increasing momentum spread of the stored beam. A more accurate analysis for ITEP-TWAC project is made by use of Monte-Carlo code. Four different storage scenarios are considered: fast scenarios with high intensity of injected beam and comparatively short accumulation time (10–20 injection cycles); slow scenarios with long accumulation time (100–200 injected cycles) (for both cases options with and without ECS have been considered). For all options, central injection scheme is used, where charge exchange target coincides with the center of the coasting beam. By optimization of the factor K b the optimal parameters (number of injections, intensity, emittance, momentum spread) have been calculated for each scenario.

It is well known that a maximal electron current in a neutralized electrom beam (NEB) is constrained by the dipole instability due to interactions between the primary electrons and the neutralizing ions. The influence of the fast secondary electrons on this instability is considered. We have examined two cases: 1) secondary electrons with full memory” (these electrons remember” the amplitude and phase of the dipole oscillations during reflections from the ends of the cooling system); 2) secondary electrons with “loss of memory”. For both cases the dependence of the NEB parameters on the concentration of the secondary electron has been investigated. Finally, we analyzed the possibility to suppress the dipole oscillations by the use of a feedback system.

Experimental and simulation data concerning fragmentation of 238 U ion beam in aluminum, copper, and stainless-steel targets with the initial energy 500 and 950 MeV=u are collected in the paper. A rangeverification technique based on depth profiling of residual activity is presented. The irradiated targets were constructed in the stacked-foil geometry and analyzed using gamma-ray spectroscopy. One of the purposes of these experiments was depth profiling of residual activity of induced nuclides and projectile fragments. Among the projectile fragments, special attention is paid to the 237 U isotope that has a range very close to the range of the primary 238 U ions. Therefore, the depth profiling of the 237 U isotope can be utilized for experimental verification of the 238 U primary-beam range, which is demonstrated and discussed in the paper. The experimental data are compared with computer simulations by FLUKA, SRIM, and ATIMA, as well as with complementary experiments.

Твердофазным методом в интервале 800-12000С из оксидов Yb(III), Cr(III) и карбонатов щелочноземельных металлов синтезированы двойные хромиты состава YbMIICr2O5,5 (MII – Mg, Ca, Sr, Ba). Установлено, что все синтезированные хромиты кристаллизуются в тетрагональной сингонии.

1. IntroductionSoft-magnetic metallic glasses are considered for mag-netic cores of accelerator radio-frequency (RF) cavities.In this particular application, they are exposed to ionirradiation, which alters their magnetic properties. Theradiation eld is rather complex (di erent particles, en-ergies and uences) because it originates from interactionof lost primary heavy ions with the beam-pipe producingdi erent secondary particles. That is why a systematicstudy of the in uence of ion irradiation on magnetic prop-erties of the soft-magnetic metallic glasses is important.Our study is connected to the AIRF project [1]. Hav-ing some experience with neutron- and laser-irradiationof di erent metallic glasses [2, 3], we started with lightions [4, 5]. However, the data for light ions cannotbe extrapolated to heavy ions, because the mechanismof radiation damage is qualitatively di erent for lightvs. heavy ions [6]. The recent work covers a,T Auand U ions irradiating ribbons of VITRAOCV

The paper presents results of FLUKA simulations of the residual activity induced by heavy ions in two target configurations representing: (1) a beam pipe of an accelerator and (2) a bulky accelerator structure like a magnet yoke or a coil. The target materials were stainless steel and copper representing the most common construction materials used for basic accelerator components. For these two materials, the inventory of the induced isotopes depends mainly on the target material and much less on the projectile species. Time evolution of the induced activity can be described by means of a generic curve that is independent from the projectile mass. Dependence of the induced residual activity on selected ion beam parameters was studied. The main goal of the study was establishing a scaling law expanding the existing proton beam-loss tolerance to heavy-ion beams. This scaling law enables specifying beam-loss criteria for projectile species from proton up to uranium at energies from $200\text{ }\text{ }\mathrm{MeV}/\mathrm{u}$ up to $1\text{ }\text{ }\mathrm{GeV}/\mathrm{u}$.

Radiation damage to various elements of the cosθ-type dipoles of the SIS300 synchrotron of the FAIR Project was calculated. Among the elements under consideration were the superconducting cable, insulating materials, and high-current by-pass protection diodes. The Monte-Carlo particle transport codes MARS and SHIELD were used to simulate propagation of the lost ions and protons, together with the products of nuclear interactions in the material of the elements. It was found that the lifetime of the protection diodes under irradiation is a more restrictive limit for the tolerable level of beam losses than the occurrence of magnet quenches.

Sub-millimetre wall thickness is foreseen for the vacuum tubes in the magnets of the superconducting dipoles of the SIS100 and SIS300 of the FAIR Project. The Bragg peak of the energy deposition by the U ions in these walls may lie dangerously close to the superconducting cables. Thus the precise knowledge of the dE/dx profile is essential for estimating the heat load by the lost ions in the vicinity of the superconducting wires. Here we present the preliminary results of the measurement of the U ion beam energy deposition profile in Cu and stainless steel targets and compare the measured data with the dE/dx calculations using different codes.

The stationary parameters of a neutralized electron cooling system (the electron current, the neutralization degree, etc.) are defined by an energy balance equation for the ions. We discuss the main sources of the ion heating: incoherent heating (natural and artificial) as well as coherent heating due to dipole oscillations excited by an interaction between the primary electrons and the ions. Analysis of beam lifetime with account of this energy balance equation and maxwellization due to intrabeam scattering permits us to estimate the stationary parameters. Results of estimations are compared with experimental data obtained at the LEAR e-cooling system.

The theory of dynamic vacuum pressure evolution in heavy‐ion accelerators in presence of beam losses is discussed. Some particular cases are considered in more detail: average pressure evolution, steady‐state vacuum pressure profile with account of beam losses, and pressure bumps induced by particle losses on the collimators. Practical applications to beam lifetime measurements at the SIS18 of GSI Darmstadt and desorption experiments at RHIC of BNL are considered.

The two-stage synchrotron complex SIS 100/SIS300 is the central part of the proposed "International Accelerator Facility for Ions and Antiprotons" at GSI. The design concept of the synchrotrons will be described with emphasis on the status of R&D work, especially on the novel rapid cycling super-conducting magnets and on the required powerful, low-frequency RF-systems. Furthermore studies are discussed, which refer to the life time of intermediate charged heavy ions and the dynamic vacuum pressure instability induced by ion beam desorption.

Charge neutralisation of the cooling electron beam, e.g. by stationary ions produced from the residual gas, is desirable to compensate the space-charge induced velocity spread which tends to reduce the cooling force. However, it has been demonstrated by Parkhomchuk and collaborators (1993) that two-stream instabilities, especially transverse dipole modes, are a serious threat to the stability. In the present report we analyse stabilising mechanisms including Landau damping, external feedback and clearing of reflected electrons. Experimental results at LEAR (the Low Energy Antiproton Ring at CERN) are discussed in a companion paper at this conference.

Finemet and Vitrovac±R 6025 metallic glasses were irradiated by light (N) and heavy (Au and Ta) ions at different energies from 110 keV to 250 MeV/u (MeV per mass unit) and fluences from 1 £ 1011 ions/cm2 to 1£1017 ions/cm2. They were analysed by the Mossbauer spectrometry and magnetic susceptibility measurements. Qualitative differences were observed between the radiation effects caused by light and heavy ions.

A numerical code for simulation of evolution of ion distribution functions during storage process has been proposed. The code based on Monte-Carlo method and «macroparticle» type simulation allows to estimate growth rates of the beam emittance and momentum spread due to an intrabeam scattering and an interaction with the stripping target for beams with non-Gaussian distribution function and permits to follow the process of particle losses as well. The algorithm of the code has been described, the code has been tested and results of its application to TWAC project have been given and discussed.

It is well known that the electron current in a neutralised electron cooling system is limited by drift dipole instability which appears due to interaction between the cooling electron beam and the neutralising ions. This strong nonlinear system has specific features: there is only “internal” (for neutralising ions) nonlinearity due to ion Coulomb field inside the electron beam, and there is strong “external” nonlinearity outside the electron beam due to nonlinear field of the electrons. To investigate a mechanism of Landau damping in the system we calculated numerically free oscillations of the ion beam center of gravity for fixed electron beam center. The results have shown that “internal” nonlinearity does not lead to damping of this coherent oscillation, which may appear only due to “tail” ions interacting with “external” nonlinearity.

Radiation effects on semiconductor devices is a topical issue for high-intensity accelerator projects. In particular it concerns Charge-Coupled Device (CCD) cameras, which are widely used for beam profile monitoring and surveillance in high radiation environment. One should have a clear idea of short and long term radiation effects on such devices. To study these effects, a CCD camera was placed in positions less than half meter away from beam loss point. Primary heavy ion beam of 0.95GeV/n Uranium was dumped into a thick aluminium target creating high fluences of secondary particles (e.g., gammas, neutrons, protons). Effects of these particles on CCD camera were scored with LabView based acquisition software. Monte Carlo calculations with FLUKA code were performed to obtain fluence distributions for different particles and make relevant comparisons. Long term total ionising dose effects are represented by dark current increase, which was scored throughout experiment. Instant radiation effects are represented by creation of charge in CCD cells by ionising particles. Relation of this charge to beam intensity was obtained for different camera positions and fluences within 5 orders of magnitude ranges. With high intensities this charge is so high that it may dramatically influence data obtained from CCD camera used in high radiation environment. The linearity of described above relation confirms linear response of CCD to ionizing radiation. It gives an opportunity to find a new application to CCD cameras as beam loss monitors (BLM).