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The main tasks performed for the automation of the Gas-Dynamic Trap Facility are described. The principles for the installation of the facility's existing and future control systems are considered. The design of the data-acquisition system, which is based on PC-compatible computers and supported by devices made to different technological standards, is reviewed. The construction of the control system for atom injection, which is based on the existing data-acquisition system, is described. [ABSTRACT FROM AUTHOR]

The ITER thermonuclear reactor is being built in France near the Cadarache nuclear center jointly by the countries participating in the project—Russia, the European Union, China, India, Korea, Japan, and the United States. The project plans the remote scientific participation in the pilot program and access to data from home agencies. The Russian Center for Remote Participation is being created in Troitsk at the Russian Domestic Agency ITER (Institution Project Center ITER) and currently the most advanced in terms of available functionality; on its basis, the joint work is carried out with the International Organization ITER (IO ITER) for developing technologies and principles of remote participation in the experiment for other participants. The article presents the results of investigations on protocols, methods, and channels for data transmission through existing networks and related information security issues including the network zoning. The elements of access to the ITER real-time data acquisition system through the EPICS facility control system gateway are described, various tools for remote participation planned for use within the ITER project, such as screen sharing and real-time data viewing, are tested. On the basis of the results of the work of the IO ITER, the requirements are formulated for remote connection of partners to the ITER resources. [ABSTRACT FROM AUTHOR]

The ([sup 6]Li, [sup 7]Be) and ([sup 6]Li, [sup 7]Li) reactions on [sup 6]Li and [sup 7]Li nuclei were investigated in the angular interval 0°–20° in the laboratory system at a [sup 6]Li energy of 93 MeV. In addition to low-lying states of the [sup 5,6]He and [sup 5,6]Li nuclei, broad structures were observed near the t([sup 3]He) + d and t([sup 3]He) + t thresholds at the excitation energies of 16.75 (3/2[sup +]) and ∼20 MeV (for [sup 5]He), 16.66 (3/2[sup +]) and ∼20 MeV ([sup 5]Li), 14.0 and 25 MeV ([sup 6]He), and ∼20 MeV ([sup 6]Li). The angular distributions measured in the [sup 7]Li([sup 6]Li, [sup 7]Be)[sup 6]He reaction for transitions to the ground state (0[sup +]) and excited states at E[sub x] = 1.8 MeV (2[sup +]) and 14.0 MeV of the [sup 6]He nucleus were analyzed by the finite-range distorted-wave method assuming the 1p- and 1s-proton pickup mechanism. The ([sup 6]Li, [sup 7]Be) and ([sup 6]Li, [sup 7]Li) reactions were shown to proceed predominantly through the one-step pickup mechanism, and the broad structures observed at high excitation energies are considered as quasimolecular states of the t([sup 3]He) + d and t([sup 3]He) + t types.© 2002 MAIK “Nauka / Interperiodica”. [ABSTRACT FROM AUTHOR]

The precise and express analysis of nanocarbon materials chemistry continues to be one of the key tasks in the study and the application of these unique structures. Despite the large variety of analytical techniques that have been commonly used for this purpose, the development of new methods that will further expand the efficiency of nanocarbon material characterization is still needed. Herein, the applicability of laser-induced breakdown spectroscopy (LIBS) towards studying the chemical composition of different types of nanocarbon structures was investigated. Graphene oxide, reduced graphene oxide (analogous of pristine graphene) and detonation nanodiamonds were chosen as the most attractive representatives of nanocarbon materials. The as-obtained results demonstrate that the functionalization parameters, such as the functionalization degree and predominant type of the functional groups, can be effectively determined on the basis of the analyzed plasma emission spectra. Furthermore, the presence of various inorganic contaminants can be identified using the LIBS technique. When compared to conventional approaches that study samples in the form of thick pellets, thin films of nanocarbon structures on various substrates were successfully analyzed using the LIBS technique. Several experimental features arise in this case, in particular, the possible ablation of wafer and formation of a thermal emission background. To overcome these challenges and to obtain reliable informative spectra, adjustment of the ablation parameters and additional spectra processing procedures were applied. As a result, the LIBS method can be a valuable and simple tool for quality control and the characterization of various nanocarbon structures. [ABSTRACT FROM AUTHOR]

Elastic and inelastic scattering of -particles at 48.1MeV and 3He at 60MeV on O nuclei has been measured with excitation of states at 6.05 (0)-6.13 (3)MeV, 6.92 (2)-7.12 (1)MeV and 8.87 (2)MeV. The center-of-mass beam momenta are the same for these two strongly absorbed particles. Analysis of angular distributions was performed in the frameworks of the optical model, the coupled channels method and the Distorted Wave Born Approximation (DWBA). A good description of experimental data was obtained over the full angular range without taking into account the spin-orbit interaction and the cluster transfer mechanism with real potentials that have volume integrals of about 400MeV fm3. Collective and microscopic models were used in the analysis of the inelastic scattering. The values of the octupole deformation lengths were extracted. It is shown that nuclear rainbow effects appear not only in the elastic, but also in the inelastic scattering with excitation of the 3 state of O. [ABSTRACT FROM AUTHOR]

Tokamak diagnostic settings are repeatedly modified to meet the changing needs of each experiment. Enabling the remote diagnostic control has significant challenges due to security and efficiency requirements. The Operation Request Gatekeeper (ORG) is a software system that addresses the challenges of remotely but securely submitting modification requests. The ORG provides a framework for screening all the requests before they enter the secure machine zone and are executed by performing user authentication and authorization, grammar validation, and validity checks. A prototype ORG was developed for the ITER CODAC that satisfies their initial requirements for remote request submission and has been tested with remote control of the KSTAR Plasma Control System. This paper describes the software design principles and implementation of ORG as well as worldwide test results. [ABSTRACT FROM AUTHOR]

A unified description of existing experimental data on alpha-particle scattering by 6Li over the broad energy range from 18 to 166 MeV was obtained with allowance for channel-coupling effects and mechanisms involving the exchange of a deuteron cluster. Angular distributions were analyzed on the basis of the optical model and the coupled reaction channels method. It was shown that the inclusion of channel coupling and the contributions from one- and two-step exchangemechanismsmakes it possible to describe special features of the behavior of differential cross sections for both elastic and inelastic scattering in a full energy range. Optimum values found for the parameters of optical potentials agree with the parameters of the global potential proposed previously for nuclei in the mass region A > 12. [ABSTRACT FROM AUTHOR]

Low-energy spectra of the 8, 10He nuclei were investigated in the ( t, p) -type reactions at small centre-of-mass angles using ∼ 25 AMeV beams of 6He and 8He nuclei. The 0+ ground state (g.s.) of 8He and excited states, 2+ at 3.6-3.9MeV and (1+) at 5.3-5.5MeV, were populated with cross-sections of 200, 100-250, and 90-125μb/sr, respectively. To account for a near-threshold anomaly observed in the 8He spectrum the population of a 1- continuum (soft dipole excitation) was considered. The lowest-energy group of events in the 10He spectrum was observed at ∼ 3 MeV with a cross-section of ∼ 140 μb/sr. This result is consistent with the previously reported observation of 10He providing a new g.s. position for 10He at about 3MeV. [ABSTRACT FROM AUTHOR]

Missing mass spectra for 8He and 10He obtained in the reactions 3H(6He, p)8He and 3H(8He, p)10He, respectively, are presented. [ABSTRACT FROM AUTHOR]

The spectra of the 11C and 10C nuclei from the 7Li(7Li,11C)3n and 7Li(7Li,10C)4n reactions, respectively, have been measured at a 7Li energy of 82 MeV and an angle of 2° up to excitation energies of 20–30 MeV of the desired multineutrons. The experiments were carried out with a magnetic separator, which made it possible to significantly increase the intensity of a beam by removing scattered particles and to carry out small-angle measurements. The energy spectra are well described by four- and five-particle phase spaces. No evidence has been found for the existence of nuclear stable and resonance states (with Γ < 3 MeV) of multineutrons. The upper limits have been obtained for the cross sections for the formation of nuclear stable states of 3n (1.4 nb/sr) and 4n (0.1 nb/sr) in the center-of-mass system. © 2005 Pleiades Publishing, Inc. [ABSTRACT FROM AUTHOR]

Provides a corrected reprint to an article previously published in the June 1998 issue of the 'Journal of Experimental and Theoretical Physics.'

The interaction in a system of two neutrons (2n) in the reaction T(d, [sup 3]He) at energy E[sub d] =31 MeV is investigated experimentally. Nuclear-unstable [sup 2]n, with a decay width Γ=(1.1±0.2) MeV , is observed with a large transverse cross sections in the interval of angles from 6° to 13°(dσ/dΩ(6°)∼10 mb/sr in the center-of-mass system). Two wide energy peaks were observed in the [sup 3]He spectra. It is proposed that broad resonances with energies E[sup *]=(3.6±0.3) and E[sup *]∼11.8 MeV, populated in the reaction T(d, [sup 3]He), are excited in the n–n system. Their energy positions satisfy the interval rule E[sub 4]:E[sub 2]≅3.3, indicating the possible existence of a “rotational band” with the characteristics 2[sup +] and 4[sup +] . The “radius” of the dineutron is estimated from the relation ΔE=h[sup 2]l(l+1)/2μR[sup 2] to be ∼8 fm. © 1998 American Institute of Physics. [ABSTRACT FROM AUTHOR]