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Abstract Among the peripheral instabilities observed at the Globus-M2 tokamak, two types of edge localized modes (ELMs) are brought into focus: ELMs synchronized and desynchronized with the sawtooth oscillations. The desynchronized ELMs appear in regimes that are characterized by high values of pressure in the pedestal, pped ≥ 3 kPa, and they are observed in discharges with the toroidal magnetic field BT > 0.6 T and plasma current IP > 0.3 MA. The desynchronized ELMs belong to the type-III/V with the dominating effect of the peeling mode. The synchronized ELMs were observed in a wider range of discharge parameters, including at BT < 0.6 T and IP < 0.3 MA. Calculations of the stability of the peeling-ballooning (PB) mode showed that at pedestal width ψnorm = 0.09 and pped > 3.5 kPa, destabilization of PB modes is possible without additional influence. Experimental data shows that the microtearing mode plays a dominant role in the pedestal. The microtearing mode does not allow the pedestal at Globus-M2 tokamak to reach the state of the unstable kinetic ballooning mode (KBM), which explains the low predictive power of the EPED model at this tokamak.

Abstract NBI-assisted plasma heating with one or two injectors of fast neutral atoms was studied at the Globus-M2 spherical tokamak at the toroidal magnetic fields of 0.8–0.9 T and plasma currents of 0.35–0.4 MA. Measurements of the spatial temperature and electron density distributions, performed using the Thomson scattering diagnostics, showed a twofold increase in heating of plasma electrons during the injection of neutral particles with energies of up to 45 keV at the beam power of 0.75 MW, as compared to the ohmic heating regime. Switching on the second additional beam with the particle energy of up to 30 keV and power of up to 0.5 MW resulted in obtaining the hot ion mode in the range of mean plasma densities of (1.6–10) × 1019 m−3. According to the data of active spectroscopy and neutral particle analyzer diagnostics, in the hot zone, the ion temperature reached 4 keV at the plasma density of 8 × 1019 m−3, which is more than 2.5 times higher than the electron temperature.

A convenient tabular format for the description of statistical methods and software in scientific publications is proposed. It is recommended to include the name of the software, its version or update date, the name of the procedures used and their intent, obligatory references, and URL

An array of ten built-in divertor probes was installed on the lower dome of the Globus-M spherical tokamak. It was used to measure the profiles of the floating potential, electron temperature, ion saturation current, and heat flux density to the divertor. It is demonstrated that there is a sharp change in the floating potentials of the probes located near the outer separatrix leg at the development of the peripheral instability.

The article presents the results of studying the transfer of heat and particles in the Globus-M2 spherical tokamak in discharges with neutral injection at the current ramp up. An atomic beam was injected into the tokamak plasma at a fixed toroidal magnetic field of 0.7 T. The plasma current on the plateau was varied in the range 0.2–0.3 MA. Based on the electron temperature and concentration spatial distributions measured by the Thomson scattering method, the transport of heat and particles in plasma was simulated using the ASTRA code. The energy confinement time of the plasma was determined, as well as estimates of the coefficients of thermal diffusivity and diffusion was made.

Globus-M2—a new 1-Tesla spherical tokamak—was recently launched. The main features and research directions of this machine in scope of fusion–fission reactor development are described. Main results of the first experimental campaign with toroidal magnetic field up to 0.73 T and plasma current up to 0.33 MA are discussed. Significant improvement of the discharge parameters as compared to Globus-M was achieved. Plasma total stored energy higher than 7 kJ was obtained. Energy confinement time increase was consistent with predictions by spherical tokamak scalings. Toroidal Alfven eigenmode-induced losses decrease with increase of plasma current and toroidal magnetic field. For the first time, LHCD with the toroidal wave slowing-down was successfully used at a spherical tokamak.

Introduction Physical exercise (PE) is a necessary part in the treatment of patients with chronic heart failure (CHF), which is stated in the European Society of Cardiology guidelines and the Russian Heart Failure Society guidelines. However, this type of non-drug treatment is still not sufficiently used in HF patients in Russia.Aim To study the current involvement of HF patients in PT and to describe psychosocial factors that influence the patients’ willingness to exercise and potential barriers and motivations for PE.Methods This study was designed as an in-moment survey. Patients with CHF who visited clinics in 7 cities of the Russian Federation in 2018 as a part of European Heart Failure Awareness Days were provided with a self-administered questionnaire containing questions about their social and educational status, attitude to PT as a method of treatment, and factors motivating and demotivating them to participation in training sessions. The survey participants were also asked a question about their source of information about exercise in HF. Physicians filled in the items describing HF clinical manifestations (left ventricular ejection fraction (EF) and HF functional class (FC)). Code numbers were used for further identification of the participants and to protect their confidentiality. Statistical analysis was performed with the StatXcat-8 program. Limits of exact confidence intervals (CIs) were provided both for fractions and parameters of polynomial distribution. CI limits for differences and fractions were calculated using MOVER. Age was analyzed using the PAST program.Results The study included 560 patients with HF; 52 % of them were women (mean age, 64; 95 % CI: 63–65 years). Women were 3 years older than men (95 % CI: 1.3–4.9 years). 501 (89.5 %) patients had FC II–III; 265 (49 %) patients had HF with low EF. 350 (62 %) patients had comorbidities: 41.4 % of patients had diabetes mellitus and 25.4 % of patients had arthritis. Only 91 (17 %) patients reported exercising. Patients younger than 65 exercised significantly more frequently than older ones (odds ratio (OR), 1.7, 95 % CI: 1.0–2.7, рConclusion The factors that positively influence the willingness to exercise include male sex, higher level of education, younger age, and better perception of the own health condition. 62 % of patients indicated poor health as the major barrier for participation in training. On the whole, the awareness of patients about PT benefits for health in HF was low. To our opinion, this was a serious factor of the extremely low involvement of patients in PT. Only 55 % of patients knew that PT could be a method for HF treatment, and, furthermore, only 50 % of patients received this information from their physicians.

Aim. Health-related quality of life in patients with arterial hypertension (HTN) is still determined by only generic patient-reported outcome measures (PROMs), although disease-specific ones are more reliable and highly valid. Previously, we reported the results of development and item-selection process of the new Russian HTN-specific PROM. The purpose of this last stage was to confirm validity, reliability, responsiveness and sensitivity of the scale and to present its final version.Material and methods. Analysis was done using data from a mass survey of patients with Grades 1-3 HTN (n=359, aged 25 to 91 y. o.) and healthy volunteers (n=48, aged 23 to 65 y.o), 407 returned questionnaires. We conducted two exploratory factor analyses (EFA) with the intermediate version of the PROM (80 questions, 20 of them HTN-specific). The Cattel’s scree test was used to select the optimal number of factors. After removing the items with a low factor loadings, a confirmatory factor analysis (CFA) was performed to assess the model’s fitindexes adequacy. The core indexes to be measured were SRMR, RMSEA, CFI. Finally, the PROM’s reliability (Cronbach’s α and McDonald’s ω) and criterion validity (responsiveness) were evaluated.Results. Both EFA with oblique and varimax rotation showed 35 questions have factor loadings ≥0,5 and assigned to one of 5 factors. The basic structure of the PROM was retained for further CFA. Most of indices of fit measured met the requirements: SRMR was 0,08, RMSEA was 0,07 (90% CI (0,07-0,08)) and CFI was 0,08, which confirms the construct validity. Both Cronbach’s α and MacDonald’s ω of each of the domains were ≥0,80 and the whole scale was 0,89 confirming satisfactory reliability. Scores of the questionnaire were positively correlated with the severity of HTN (pConclusion. Sequentially addressing of exploratory and confirmatory factor analyses and assessment of reliability and responsiveness allowed to form the final version of the patient-reported outcome measure for arterial hypertension. The new Russian-language questionnaire is a useful and feasible tool for routine practice and clinical trials.

A method of plasma boundary location based on last closed magnetic surface position detection as a maximum of electrostatic potential measured using Langmuir probes is presented. It is demonstrated that the method can be used for an absolute calibration of magnetic diagnostics of plasma position (TUMAN-3M) and as an independent diagnostic tool (Globus-M).

The results of experiments and simulations of the transport of heat and particles in the Globus-M spherical tokamak are presented. Investigations were carried out in the ohmic mode in hydrogen and deuterium plasma. It is shown that in the phase of current growth under the same initial conditions, as long as the condition is met at which the minimum of the safety factor exceeds unity, two scenarios of discharge development are possible: with an electron temperature dive or with an electron density peak. After the safety factor reaches the value of 1, the differences are no longer observed. Modeling of transport processes using the ASTRA code showed that the dive of the electron temperature and density is a consequence of the decrease in the transport of heat and particles in the plasma core (i.e., the presence of internal transport barriers).

Fruits and berries are the most important sources of a wide range of biologically active substances, including vitamin C, carotenoids, flavonoids, anthocyanins. In order to replenish and update data on the content of food and biologically active substances in the tables of the chemical composition of food products, a study of the content of mono- and disaccharides, dietary fiber was carried out; vitamins C, B1, B2 and E, minerals and trace elements; flavonoids (in terms of rutin), anthocyanins; organic and hydroxycinnamic acids, stilbenoids in various varieties of 16 fruit and berry crops.

The work presents the results of the energy confinement study carried out on the compact spherical tokamak Globus-M2 with a toroidal magnetic field as high as 0.8 T. A reproducible and stable discharge was obtained with the average plasma density (5–10) × 1019 m−3. Despite the increase in the magnetic field, the neutral beam injection (NBI) led to clear and reproducible transition to the H-mode accompanied by a decrease in the turbulence level at the plasma edge. NBI allowed effectively heat the plasma: electron and ion temperatures in the plasma core exceeded 1 keV. Compared to the previous experiments carried out with a toroidal magnetic field as high as 0.4 T plasma total stored energy was increased by a factor of 4. The main reason or this phenomenon is a strong dependence of the energy confinement time on the toroidal magnetic field in the spherical tokamak. It was experimentally confirmed that such kind of dependence is valid for ST with magnetic field up to 0.8 T. It has also been shown that the enhancement of the energy confinement in Globus-M2 with collisionality decrease is associated with an improvement of both electron and ion thermal insulation.

In the course of the study, it was determined that the chemical composition and nutritional value of the Viburnum vulgaris is explained by a group of substances of different nature. Their qualitative and quantitative component depends, first of all, on the growing region. The national economic value of viburnum is great—from culinary delights to medicines. The article presents the biochemical composition of the leaves of the viburnum of various varieties, which indicates the possibility of using viburnum leaves in the production of food, including a functional orientation.

Currents structure in the scrape-off layer (SOL) of a tokamak is analyzed. It is demonstrated that poloidal currents measured in the experiments are a combination of several current types of different physical nature. Besides known Pfirsch-Schluter (PS) currents and thermoelectric currents, so-called PCC (plate closing currents) flowing to/from the divertor plates are also analyzed. The latter close radial currents in the SOL and below/above the X-point. In particular, current flowing to the outer plate in the private flux region (PFR), opposite to thermolelectric current is predicted for the standard single-null configuration and favorable direction of ∇B drift (∇B drift of ions is directed towards active X-point). In addition, a pair of currents to and away from the outer plate should flow. In the single-null configuration they are often masked by a larger thermoelectric current, however for the connected double null (CDN) case, where thermoelectric current is strongly reduced due to less temperature asymmetry, these currents dominate. The suggested physical model is supported by results of simulations performed with SOLPS-ITER transport code. Simulations were done for ASDEX-Upgrade (AUG), L-mode , single-null configurations, and for Globus-M H-mode, both disconnected and connected double null configurations. Results of the simulations are compared with probe measurements for AUG and Globus-M tokamaks, and reasonable agreement has been found.

The current work reports on the significant rise of the fusion triple product in experiments carried out on the compact spherical tokamak (ST) Globus-M2 with a twofold increase in the toroidal magnetic field. A tenfold rise in the n . T . τ E product was recorded during an increase in the magnetic field from 0.4 to 0.8 T and the plasma current from 0.25 to 0.4 MA at an unchanged auxiliary heating power value. Limited reasons may affect this positive trend, among which are energy confinement improvement and an increase in the efficiency of neutral beam heating. Despite the increase in the magnetic field, the neutral beam injection (NBI) led to clear and reproducible transition to the H-mode accompanied by a decrease in the turbulence level at the plasma edge. It was experimentally confirmed that strong dependence of the energy confinement time on the magnetic field value is conserved at a higher magnetic field approaching 0.8 T. Enhancement of energy confinement is connected to a collisionality (ν *) decrease. While for conventional tokamaks the confinement dependence on collisionality becomes weaker with decreasing ν * dependence, in the ST, in contrast, we observe its strengthening.

When assessing the combined action of genes on the quantitative or qualitative phenotype we encounter a phenomenon that could be named the “paradox of the risk score summation.” It arises when the search of risk allele and assessment of their combined action are performed with the same single dataset. Too often such methodological error occurs when calculating the so called genetic risk score (GRS), which refers to the total number of alleles associated with the disease. Examples from numerous published genetic association studies are considered in which the claimed statistically significant effects can be attributed to the “risk score summation paradox.” In the second section of the review we discuss the current modifications of multiple regression analysis addressed to the so called “n ≪ p problem” (the number of points is much smaller than the number of possible predictors). Various algorithms for the model selection (searching the significant predictor combinations) are considered, beginning from the common marginal screening of the “top” predictors to LASSO and other modern algorithms of compressed sensing.

Current structure in the scrape-off layer (SOL) of a tokamak is analyzed. It is demonstrated that poloidal currents measured in the experiments are a combination of several current types with different physical nature. Besides the known Pfirsch–Schlüter currents and thermoelectric currents, so-called plate closing currents flowing to/from the divertor plates are also analyzed. The latter close radial currents in the SOL and below/above the X-point in the SOL and private flux region (PFR). In particular, the current flowing to the outer plate in the PFR, opposite to the thermoelectric current, is predicted for the standard single-null configuration and favorable direction of ∇ B drift. In addition, a pair of currents should flow to and away from the outer plate. In the single-null configuration, they are often masked by a larger thermoelectric current. However, for the connected double null (CDN) case, where the thermoelectric current is strongly reduced due to smaller temperature asymmetry, these currents dominate. The suggested physical model is supported by the results of simulations performed with the SOLPS-ITER transport code. Simulations were done for ASDEX Upgrade (AUG), L- and H-modes, single-null configurations, and for Globus-M H-mode, both disconnected and CDN configurations. Results of the simulations are compared with probe measurements for AUG and Globus-M tokamaks, and reasonable agreement has been found. The role of parallel currents in the formation of the potential maximum/minimum in the vicinity of the X-point for strongly detached regimes is also analyzed.

A new generation spherical tokamak Globus-M2 was launched in 2018. It keeps size of Globus-M, however new electromagnetic system allows achieving higher toroidal magnetic field and plasma current. First experimental campaign with the toroidal magnetic field 0.7 T and plasma current up to 300 kA was carried out in 2019. Increase in the toroidal magnetic field and plasma current resulted in overall improvement of the discharge parameters. Significant plasma temperature growth and neutron rate increase was obtained. Record stored energy, which is approximately one and a half times higher than in the Globus-M experiments, was reached. Toroidal lower hybrid wave launch provided noticeable current drive. Preparation for the next experimental campaigns with the higher toroidal magnetic field and plasma current are on the way.

Correct harmonized statistical re-analysis of the data published in this Journal by I.V.Polyakova et al. (2014) clearly shows that, contrary to the authors' opinion, the distribution of genotypes among residents of besieged Leningrad and the residents of the North-West region of Russia appeared to be statistically indistinguishable in all five genes studied. The main causes of the erroneous conclusions of the authors are neglecting the problem of multiple comparisons and fundamental impossibility of sampling adequate control group. A scheme for harmonized statistical analysis of such data is presented. It implies not only frequentist but Bayesian point and interval estimates for genotype proportions and their differences, for fixation index (coefficient of inbreeding) FIS, for the effect size φ based on χ2 statistic (contingency coefficient) and for the achieved power (1 - β), as well as estimates of posterior probabilities for the null hypothesis P(H_0 |D), Bayes factors 〖BF〗_01, observed p-values, p_obs, with the prediction intervals, and p-values adjusted for the multiplicity of null hypotheses tested (P_S).Корректный статистический анализ данных, опубликованных в журнале «Успехи геронтологии» И.В.Поляковой и соавт. (2014), убедительно свидетельствует, что вопреки мнению авторов, распределения генотипов у жителей блокадного Ленинграда и у жителей Северо-Западного региона России статистически неразличимы по всем пяти изученным генам. Основными причинами ошибочных выводов авторов являются пренебрежение проблемой множественных сравнений и невозможность сформировать адекватную контрольную группу. Представлена схема гармонизированного статистического анализа подобных данных, которая включает не только частотнические, но и бейзовские точечные и интервальные оценки для долей генотипов и их разностей, для индекса фиксации (коэффициента инбридинга) F_IS, для размера эффекта φ (коэффициента сопряженности Пирсона) и для достигнутой мощности (1 – β), а также оценки апостериорных вероятностей для нулевой гипотезы P(H_0 |D), бейзовы факторы 〖BF〗_01, значения p_obs с границами предсказательного интервала и значения P_S с поправкой на множественность проверяемых нулевых гипотез.

The analysis of the IFN-status of healthy full-term neonatal infants and their healthy mothers with modern statistical methods was conducted. It was established that the IFN status of healthy full-term neonatal infants differs from the same of their mothers with higher occurrence of IFNs and strengthened induced production of IFNα/β and IFNγ. The statistically significant interaction between indicators of the IFN status of newborns and their mothers has been revealed. The obtained data is important for assessment of nonspecific resistance in system mother–newborn.

The results from calculations of the anisotropic fast particle distribution function in the Globus-M/M2 spherical tokamaks are presented. The calculations were performed using the NUEBAM code, the reasons for the anisotropy occurrence are discussed (injection geometry, low toroidal magnetic field and plasma current, presence of neutral particles). It is shown that the anisotropy decreases with increasing toroidal magnetic field and plasma current: the density of the slowed down fast ions with energies of E < 4 keV almost doubles and the averaged perpendicular velocity of fast ions increases.

A fast scanning probe which can penetrate inside the separatrix during discharge was developed for Globus-M2. The probe has been designed to move various sensor pins into the scrape-off layer. The driving force is provided by a crank-slider mechanism which is ensured maximum linear speed about 4 m/s. The paper presents probe head and drive system description.

Plasma parameters in the Globus-M spherical tokamak have been measured upon injection of a deuteron beam with energy about 30 keV and a power of up to 700 kW. Dependences of the ion temperature and neutron yield on the plasma current and density and the gap width between the wall and plasma are considered. Possible characteristics of fast-ion confinement in the modified Globus-M2 tokamak are discussed.

Experimental results on the generation and maintenance of the toroidal current in the Globus-M spherical tokamak by using waves in the lower hybrid frequency range without applying an inductive vortex electric field are presented. For this purpose, the original ridge guide antennas forming a field distribution similar to that produced by multiwaveguide grills were used. The high-frequency field (900 MHz) was used for both plasma generation and current drive. The magnitude of the generated current reached 21 kA, and its direction depended on the direction of the vertical magnetic field. Analysis of the experimental results indicates that the major fraction of the current is carried by the suprathermal electron beam.

When assessing the combined action of genes on the quantitative or qualitative phenotype we encounter a phenomenon that could be named the “paradox of the risk score summation.” It arises when the search of risk allele and assessment of their combined action are performed with the same single dataset. Too often such methodological error occurs when calculating the so called genetic risk score (GRS), which refers to the total number of alleles associated with the disease. Examples from numerous published genetic association studies are considered in which the claimed statistically significant effects can be attributed to the “risk score summation paradox.” In the second section of the review we discuss the current modifications of multiple regression analysis addressed to the so called “n ≪ p problem” (the number of points is much smaller than the number of possible predictors). Various algorithms for the model selection (searching the significant predictor combinations) are considered, beginning from the common marginal screening of the “top” predictors to LASSO and other modern algorithms of compressed sensing.

In the final Globus-M experimental campaign B tor and I p were raised by 25% up to 0.5 T and 250 kA, respectively, expanding available range of experimental parameters. In these experiments an overall improvement in plasma performance was observed, plasma total stored energy and neutron rate increased significantly. The energy confinement time dependence on B tor and n e was close to linear. L-H transition threshold was 5–10 times higher than threshold predicted by the scaling. Despite the small plasma-wall distance, the level of radiation losses in the main plasma volume was relatively small and decreased as B tor rised. An increase in B tor and I p led to a decrease in the sawtooth-induced losses. While a rise in the plasma current led to a decrease of fast ion losses per TAE burst at the same amplitude; frequency of bursts and their amplitude increased. Doppler backscattering, applied to study TAE localization for the first time, revealed that TAE fluctuations are localized in the region of normalized minor radii ρ = 0.5–0.75. A new movable 9-pin head probe provided data, necessary for power decay length scaling investigation. Significant power decay length contraction, stronger than predicted by Eich’s scaling, was observed.

The Globus-M2 spherical tokamak is the considerably upgraded Globus-M facility. Its technical parameters were increased as much as possible to achieve the promising range of physical parameters (sub-fusion temperatures and collisionality of much less than unity). These parameters will be achieved in a compact magnetic configuration similar to that of the Globus-M tokamak, the plasma current and toroidal magnetic field amounting to 0.5 MA and 1 T, respectively. The demand to increase the magnetic field and plasma current in the Globus-M2 resulted in the need for a complete redesign of the electromagnetic system because the plasma equilibrium requirements have changed and the mechanical and thermal loads have considerably increased as compared to the Globus-M. The vacuum vessel and the in-vessel components of the new Globus-M2 tokamak remain the same. Power supplies were upgraded to provide the required currents in the toroidal field coil and the central solenoid. The Globus-M2 tokamak was build up and preliminary tests were carried out. New auxiliary heating systems and diagnostics were developed and installed to be used in future experiments. Fist plasma was achieved at the Globus-M2 in April 2018.

Analysis of stability of the peeling-ballooning modes in the edge plasma of the Globus-M tokamak is presented. Studies were performed using the ideal 3D MHD code written in the BOUT++ framework. The edge localized modes which are frequently observed in the Globus-M plasma could be described using MHD theory. It was found that the parameters of the Globus-M edge plasma are in the range of stability for the peeling-ballooning modes. The instability modes with a toroidal number of n = 12 and typical distances between filaments of approximately ~12 cm were found to be the most unstable. This statement agrees with the Doppler backscattering measurements. It was also considered whether the plasma in the Globus-M2 tokamak will be stable against the PB instability.

A diagnostic system for plasma radiated power tomography on Globus-M was upgraded with a new linear array based on silicon photodiodes. The hardware of the diagnostic system based on a 256-channel tangential matrix array and a 24-channel linear array is described. The algorithm for 2D tomographic reconstruction of plasma emissivity is presented. It uses the Tikhonov regularization method and anisotropic diffusion functional as a side constraint. Simulated plasma emissivity profiles were used to test and assess the capabilities of the developed algorithm. Data analysis was carried out in ohmic and neutral beam heated discharges to demonstrate the performance of the tomography diagnostic in plasmas with different parameters. The presented results illustrate the proper functioning of the tomography system that allowed to reveal and study various plasma phenomena, including magnetohydrodynamic mode.

25th Fusion Energy Conference (FEC), Govt Russian Federat, St Petersburg, RUSSIA, OCT 13-18, 2014; International audience; In this paper we present the fusion related activities of the Plasma Physics Division at the Ioffe Institute. The first experiments on lower hybrid current drive (LHCD) in a spherical tokamak performed at the Globus-M tokamak (R = 0.36 m, a = 0.24 m, B-t = 0.4 T, I-p = 200 kA) with a novel poloidally oriented grill resulted in an RF driven current of up to 30 kA at (100kW, 2.5 GHz), exceeding the modelling predictions. At the FT-2 tokamak (R = 0.56 m, a = 0.08 m, B-t = 3T, I-p = 30 kA) experiments with a traditional toroidally oriented grill revealed no strong dependence of the LHCD density limit on the H/D ratio in spite of LH resonance densities differing by a factor of 3. Microwave Doppler reflectometry (DR) at the Globus-M, and DR and heavy ion beam probe measurements at the tokamak TUMAN-3M (R = 0.53 m, a = 0.24 m, B-t = 1.0T, I-p = 190 kA) demonstrated geodesic acoustic mode (GAM) suppression at the L to H transition. Observations at FT-2 using Doppler Enhanced Scattering showed that the GAM amplitude is anti-correlated both spatially and temporally to the drift turbulence level and electron thermal diffusivity. For the first time turbulence amplitude modulation at the GAM frequency was found both experimentally and in global gyrokinetic modelling. A model of the L-H transition is proposed based on this effect. The loss mechanisms of energetic ions' (EI) were investigated in the neutral beam injection (NBI) experiments on Globus-M and TUMAN-3M. Empirical scaling of the 2.45 MeV DD neutron rate for the two devices shows a strong dependence on toroidal field B-t(1.29) and plasma current I-p(1.34) justifying the B-t and I-p increase by a factor of 2.5 for the proposed upgrade of Globus-M. Bursts of similar to 1 MHz Alfvenic type oscillations correlating with sawtooth crashes were observed in ohmic TUMAN-3M discharges. The possibility of low threshold parametric excitation of Bernstein and upper hybrid waves trapped in drift-wave eddies resulting in anomalous absorption in electron cyclotron resonance heating (ECRH) experiments in toroidal plasmas was identified theoretically. A novel method of radial correlation Doppler reflectometry is shown to be capable of measuring the turbulence wave-number spectrum in realistic 2D geometry. On the progress in design and fabrication of three diagnostics for ITER developed in the Ioffe institute is reported: neutral particle analysis, divertor Thomson scattering and gamma spectroscopy.

The first experiments on noninductive current drive (CD) using lower hybrid waves in a spherical tokamak are described. Waves at 2.45 GHz were launched by a 10 waveguide grill with 120° phase shift between neighbouring waveguides. The experimental results for a novel poloidal slowing-down scheme are described. The CD efficiency is found to be somewhat larger than that predicted theoretically whilst at the same time being somewhat less than that for standard tokamak lower hybrid CD. Geodesic acoustic modes (GAM) have been discovered in Globus-M. GAMs are localized 2–3 cm inside the separatrix. The GAM frequency agrees with theory. The mode structures of plasma density and magnetic field oscillation at the GAM frequency have been studied. Fast particle confinement during neutral beam injection has been investigated and numerically simulated. Alfven instabilities excited by fast particles were detected by a toroidal Mirnov probe array. Their excitation conditions are discussed and the dynamics of fast ion losses induced by Alfven eigenmodes is presented. Preliminary experiments on the isotopic effect influence on global confinement in the ohmic heating (OH) regime are described. Scrape-off layer (SOL) parameters were measured and compared with results from self-consistent integrated transport modelling. Results showed that SOL width scales inversely proportional to plasma current. The behaviour of an a priori damaged tungsten divertor plate mock-up exposed to plasma flows was investigated. Preliminary conclusions are that the initial damage gives rise to a loose layer formation with low thermal conductivity right beneath the surface. Finally, engineering design issues of the next step—Globus-M2 (1 T, 500 kA) and the status of component manufacture are described.