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A tomographic method for reconstructing the axially symmetric Dα emission profile in the ITER scrape-off layer and divertor from Dα intensity measurements in the fields of view (FoV) of Vis/IR TV and Divertor Impurity Monitor diagnostics is under development. The method takes into account the strong background signal due to stray light from divertor produced by reflections from the metal wall of the vacuum chamber. The method allows to filter out the reflections in Dα signals measured in the main chamber. The accuracy of this method is tested within the framework of a synthetic diagnostic, which uses the Raysect and Cherab numerical codes for ray-tracing simulations. The Dα emission profiles, simulated with the SOLPS and OEDGE codes, are used as synthetic experimental data. Uncertainty in light reflection properties of the first wall (FW) is the major factor affecting the accuracy of the Dα emission reconstruction. The dependence on the uncertainty in the FW surface roughness and on the ratio of diffusive to specular reflection of the error in recovering useful Dα signals (the direct light without reflections) in the FoV of the ITER main chamber H-alpha and Visible Spectroscopy Diagnostic is obtained.

The behavior of Am, Eu, Sr radionuclides was investigated by thermodynamic modeling method at heating of radioactive graphite in NaCl – KCl – Na2CO3 – K2CO3 molten salt with additives of nickel oxide NiO. The integrated thermodynamic analysis was carried out by means of TERRA software in temperature range 373-3273 K to determine possible composition of condensed and gaseous phases. It was established that americium is in gaseous state in temperature range 2773-3273 K. Europium is in the forms of gaseous EuO and Eu in temperature range 2373-3273 K. Strontium is in the forms of gaseous SrCl2, SrCl, Sr, SrO in temperature range 2373-3273 K.

The article considers the relevance of increasing the efficiency of development of offshore shelf deposits in the North Caspian, using the example of the oil and gas condensate field named after Y. Korchagin. The development of offshore fields is associated with the use of the latest expensive technologies aimed at highly efficient development of facilities with hard-to-recover hydrocarbon reserves. The involvement of field operators in the development of expensive imported technologies leads to a significant increase in the cost of oil produced. In this regard, there is a need for testing and introducing similar domestic technologies into the offshore field development process to optimize the hydrocarbon production process.

Experiments with reactor antineutrino provide a wide range of physics opportunities. Solid state scintillator detector DANSS is placed just below the core of 3.1 GW th industrial reactor of Kalininskaya Nuclear Power Plant. The detector features the world highest counting rate of 5000 neutrino events per day with the cosmic rays induced background as low as 130 events per day. The talk covers detector performance of a year and a half operation, reactor power measurements via neutrino flux and effects of fuel burning over the reactor campaign.

The method of thermodynamic simulation is used to determine the thermal diffusivity and the thermal conductivity of the melt 42 mass.% Bi-40.6 masses.% Pb-10 Macc.% Sn-7.4 mass % Cd depending on temperature. It was found that the thermal conductivity and thermal diffusivity of melts Bi-Pb-Sn-Cd, Bi-Pb-Sn, Bi-Pb differ by no more than 15%. The obtained values indicate the prospects of using this melt as a coolant.

In this paper, the thermophysical characteristics of the fullerene-argon (C32-Ar) system at atmospheric pressure are studied by thermodynamic modeling using the TERRA software system. Two groups of processes occurring in the system under consideration are determined: sublimation reactions with thermal dissociation and thermal dissociation reactions in the gas phase. The thermal physics of carbon vaporization in the gas phase is studied, the graphs of the dependence of the thermal characteristics of the C32-Ar system on temperature are constructed; the regularities in the inflection points of the graphs and changes in the compositions of the gas and condensed phases are revealed.

The behavior of some radionuclides (U, Eu, Pu) in the utilization of radioactive graphite by the combustion method in oxygen is considered. The study was carried out by thermodynamic modeling in the temperature range 300-3300 K. The main physicochemical processes occurring during oxidation were established.

Deep plasma fueling by the injection of high-speed high-density hydrogen plasma jet has been observed on Globus-M injection of unmagnetized hydrogen jet by a plasma gun led to a twofold increase of plasma core density. Presented here are the results of measurement of plasma jet velocities during the movement in the tokamak plasma. It is demonstrated that the deceleration times of the hydrogen and helium jets are in accordance with the predictions of the plasma jet penetration models based on consideration of the Alfven conductivity of the plasma and inhomogeneity and curvature of the magnetic field. It is confirmed that the main mechanism governing the penetration depth of the jets in the tokamak plasma for considered conditions is the Alfven conductivity.

The reflection of light from walls will result in parasitic signals for various optical diagnostics and can be a serious issue in ITER. In this study, we show recent progress in the assessment of the effects of wall reflections in ITER based on ray tracing simulation results. Four different diagnostics in ITER were chosen for the simulation, i.e. visible spectroscopy, infrared thermography, edge laser Thomson scattering, and charge exchange recombination spectroscopy.

The DANSS project is aimed at creating a relatively compact neutrino spectrometer which does not contain any flammable or other dangerous liquids and may therefore be located very close to the core of an industrial power reactor. As a result, it is expected that high neutrino flux would provide about 15,000 IBD interactions per day in the detector with a sensitive volume of 1 m3. High segmentation of the plastic scintillator will allow to suppress a background down to a ~1% level. Numerous tests performed with a simplified pilot prototype DANSSino under a 3 GWth reactor of the Kalinin NPP have demonstrated operability of the chosen design. The DANSS detector surrounded with a composite shield is movable by means of a special lifting gear, varying the distance to the reactor core in a range from 10 m to 12 m. Due to this feature, it could be used not only for the reactor monitoring, but also for fundamental research including short-range neutrino oscillations to the sterile state. Supposing one-year measurement, the sensitivity to the oscillation parameters is expected to reach a level of sin2(2θnew) ~ 5 × 10−3 with Δ m2 ⊂ (0.02–5.0) eV2.

A method is suggested for interpreting the data from the Balmer-alpha high- resolution spectroscopy diagnostics of the edge plasma in the tokamak main chamber, which additionally uses the data from direct observation of the divertor. Such an extension of the diagnostics is motivated by the fact that in a tokamak-reactor with the metal first wall, like ITER tokamak, a significant role of the divertor stray light (DSL), which is emitted by the plasma in the divertor in the same spectral line and reflected from the first wall of the vacuum chamber to a spectrometer in the main chamber, is expected. The results of the first applications of the developed model to interpret the data from the JET-ILW tokamak experiments, which simulate the conditions of occurrence of the DSL in ITER, are discussed.

Due to the development of the ITER project, the requirements of the technical parameters of the ITER systems were more precisely and practically determined to be at higher levels. The essential increase of the ITER system characteristics happened recently. A number of prototypes were manufactured and tests were carried out. The results of the development and manufacture of 25 ITER systems, subject to the Russian Federation's obligations in the ITER project, are described.

Since ITER will be a full metallic wall machine, scattered photons from the strong emission in the divertor may distort the emission from the scrape-off layer (SOL). The influence of stray light for visible spectroscopy of H? and Be?I emissions in ITER was investigated with a ray-tracing simulation. It was found that the stray light would be always more than one order of magnitude greater than the real signal intensity for H? emission from the SOL. For Be?I emission, although the situation was better than the cases of H? measurement, the stray light could be much larger than the real signal from the SOL. In ITER, it will inevitably reduce the stray light somehow for visible spectroscopy. The effect of optical dumps embedded on first walls was investigated with the ray-tracing analysis.

This paper presents a review of the last T-11M and T-10 tokamak activity in the field of Li plasma facing component (PFC) investigation. Attention is mainly paid to the realization of the concept of closed loop lithium circulation as a solution of the PFC problem of a steady-state DT volumetric neutron source on a tokamak basis. Realization of the Li PFC concept demands the decision of three main tasks: lithium injection into the plasma, Li collection before its deposition on the vacuum vessel and the return of Li to the injection zone from the collector. This emitter–collector concept assumes that the main heat flux from a hot plasma to the PFC (limiters and divertor plates) can be dissipated on the entire vessel wall surface by non-coronal Li radiation, which will smoothen the local heat load PFC. A rail limiter on the basis of a capillary porous system manufactured from tungsten felt and provided with W wings was successfully tested in the last T-11M experiments as a prototype of steady-state Li emitter–collector. A witness-sample analysis showed that the lateral sides of the rail and ring limiters crossing the plasma scrape-off layer can collect a significant (∼80%) part of Li, injected into the plasma during discharges. This can be used in the future for closing Li loop circulation. As was shown by Li pellet injection in T-10, the probability of Li penetration into the hot plasma core from its boundary is lower than that of deuterium by a factor of 5–10. This result can explain the effect of plasma cleaning (Z eff (0) ∼ 1) during T-10 Li experiments. Some different schemes of future lithium circulation loops are discussed.

We present new measurements of the analyzing power AN in proton-proton elastic scattering in the Coulomb-Nuclear Interference region at ?s = 7.7 and 21.7 GeV obtained with the polarized atomic hydrogen jet target at RHIC. These measurements complement our earlier results at ?s = 6.8 and 13.7 GeV confirming the presence of a hadronic helicity flip amplitude contribution in proton-proton elastic scattering at lower energies (?s 13 GeV) are consistent with no hadronic helicity flip contribution.

The Siberian snakes are powerful tools in preserving polarization in high energy accelerators has been demonstrated at the Brookhaven Relativistic Heavy Ion Collider (RHIC). Equipped with two full Siberian snakes in each ring, polarization is preserved during acceleration from injection to 100 GeV. However, the Siberian snakes also introduce a new set of depolarization resonances, i.e. snake resonances as first discoverd by Lee and Tepikian [1]. The intrinsic spin resonances above 100 GeV are about a factor of two stronger than those below 100 GeV which raises the challenge to preserve the polarization up to 250 GeV. In 2009, polarized protons collided for the first time at the RHIC design store energy of 250 GeV. This paper presents the experimental measurements of snake resonances at RHIC. The plan for avoiding these resonanances is also presented.

The RHIC polarized proton complex utilizes polarimeters in each of the Blue and Yellow beams that measure the beam polarization through the p-Carbon elastic scattering process in the Coulomb Nuclear Interference kinematic region. This along with a Polarized Hydrogen Jet Target that utilizes the proton-proton elastic scattering process to first measure the analyzing power of the reaction and using the reverse process to measure the beam polarization. The latter is used to calibrate the p-Carbon polarimeters at the desired beam energy. In Run 9 RHIC ran with beams at center-of-mass energies of 200 and 500 GeV respectively. The higher beam intensities as well as the fact that the 250 GeV beam size is much smaller than that at 100 GeV resulted in significantly higher rates seen by the polarimeters and led to observed instability. In this paper, we will discuss the problems encountered and the tests that were carried out using the AGS as a proxy in an attempt to solve the problems and the path forward we took towards the upcoming polarized proton Run11.