MOST SIGNIFICANT SCIENTIFIC RESULTS OF 2018
• The response of the detector subsystems was estimated using Monte Carlo models (based on the Geant4 package) of the BM@N and MPD experiments, namely, the development and implementation of algorithms, methods and software packages for:
• To install MPD was developed a block diagram of a specialized integrated circuit (SIС) of a data concentrator, was substantiated a list of required complex functional nodes, a technology was selected, and was carried out the topological planning of node placement and the framework of SIC contact pads.
• For the BM@N experiment, was developed a technology for the manufacture of diamond-based films for use in GEMs with extremely high radiation resistance, and was developed the test detector to study GEM characteristics, and was assembled a bench, tested, and put into operation for an experimental study of the characteristics of cameras on based on GEM technology, which used in the experiment track system.
The results of the detection of an excess of muons growing with energy in extensive air showers, obtained at a unique scientific facility NEVOD, which at energies of the order of 1018eV exceed the calculated value even for the pure iron composition of primary cosmic rays, were confirmed by the Pierre Auger Observatory and received wide international recognition at the international conference UHECR-2018 held in October 2018 in Paris. An excess of muons may indicate the manifestation of new physical processes of their formation at energies above 1017 eV.
As part of the development of its own material, technical and scientific base at Scientific & Educational Centre NEVOD, together with Institute for High Energy Physics (IHEP) of National Research Centre "Kurchatov Institute", has begun the creation of the world's largest coordinate-track detector on drift chambers (TREC) for recording a near-horizontal muon flux generated by ultrahigh-energy cosmic rays. This will make it possible to find a solution to a set of problems related to the energy spectrum, mass composition, and cosmic ray interactions in the region of ultrahigh energies, including the muon riddle - an excess of muons in EAS growing with energy compared to the predictions of modern models. The detector with an area of 250 m2 will consist of 264 multiwire drift chambers with dimensions of 4000×508×112 mm3, developed at IHEP. During the reporting period, as part of the work performed, a large-scale verification of drift chambers and their electronics was carried out, was developed the first prototype of a time-to-digital converter for the TREK detector recording system, its operation was ensured and its prototype (KTUDK) included in the experimental complex of the NEVOD unique scientific facility was monitored as well as a long experiment was carried out to record single and groups of muons emitted by the DECOR and CTUDK coordinate-track detector and analyzed s experimental data. Improved methods for reconstructing multiparticle events, including using neural networks.
In 2018, in the framework of decrees of the Government of the Russian Federation, federal targeted programs, various scientific foundations, government assignments and agreements with industrial partners, work was carried out in the main scientific areas and were obtained the most important scientific results:
In 2018, according to the results of the work, were registered 14 results of intellectual activity.
MOST SIGNIFICANT SCIENTIFIC RESULTS OF 2017
- Within the framework of COHERENT international cooperation, for the first time in the world, conducted experimental observations of a new type of interaction of neutrinos with substance - elastic coherent scattering of neutrinos on heavy nuclei. The first post was published in August 2017 in the high-rated journal Science.
- For the first time in the world at the ATLAS facility at CERN, with the participation of scientists from INPhE (Institute of Nuclear Physics and Engineering), conducted an investigation of the electroweak production of Z boson with a photon, with the subsequent decay constant of the Z boson into two neutrinos. As a result, the world's best constraints on the parameters of anomalous quadruple of vertices ZZZ-gamma quantum; ZZ-gamma quantum-gamma quantum, etc.
- Computed and realized the possibility of setting an additional channel in the reactor core in Obninsk Institute for Nuclear Power Engineering (OINPE) for producing molybdenum-99 which is highly needed in nuclear medicine during diagnosis of diseases.
- Created and tested new multi-layer film screens of gradient, which are 2 times better than the previous screens of symmetrical type, protect photomultipliers from magnetic fields. These screens will be used in LHCb and SHiP installations.
- Within the framework of the work carried out on the CMS experiment: the technical project of modernization of the end calorimeters of the CMS for the operation in ultra-high luminosity was completed; calibration factors for the energy scale of the hadron calorimeter of the CMS detector were obtained from the data of 2017; according to the experimental data obtained on the physical prototype of the analog hadronic calorimeter CALICE, a comparison of the parameters of hadronic showers for absorbers from steel and tungsten was made; it has been shown experimentally that the fraction of the electromagnetic component in the case of a tungsten absorber is smaller than with a steel absorber. X-ray scanners made by employees of Institute of Nuclear Physics and Engineering (INPhE), delivered and commissioned in places of assembly muon chambers for the upgrade of the ATLAS experiment in Israel, Canada, Chile and China. когерентного рассеяния нейтрино на тяжёлых ядрах. Первое сообщение опубликовано в августе 2017 года в высоко-рейтинговом журнале Science.
- The track characteristics of the transient radiation detector (TRT) were studied in the ATLAS experiment at high loads. It is shown that the detector makes a significant contribution to the measurement accuracy of particle pulses up to loads up to 90%.
- A prototype of the pre-amplification subsystem for the signals of the DSNF fission chambers was developed.
- As part of the development of a new FIT detector for the modernization of the ALICE experiment: - a study of the parameters of a new (upgraded to our requirements) photomultiplier XP85012/XP85112 in the laboratory and on the accelerator; - a study of the aging of the photomultiplier XP85012, which showed the possibility of using it in future experiments on ALICE; - The Cherenkov detectors were tested on the basis of the modernized photomultipliers XP85112 and XP85012, obtained a temporary resolution for the registration of single-charge relativistic particles of 10 pc.
- In the framework of the T2K experiment, a new result was obtained for the direct search for the violation of CP symmetry in neutrino oscillations, 89 electron neutrinos and 7 electron antineutrinos were registered in The long-range Super-Kamiokande detector, as a result of the analysis of the CP, the preservation is excluded at the level 2σ and an indication is given for the maximum CP violation and the CP value of the odd phase about - π/2.
- Within the framework of the Baby-MIND (NP05) project and the CERN Neutrino platform: in 2017, the creation of a magnetic detector for the neutrino Baby-MIND for measuring neutrino cross sections in the energy region of about 1 GeV, a magnetic field of about 1.5 T allows reliable identification of the particle charge, with Participation of employees and students of the Institute of Nuclear Physics and Engineering (INPhE) has developed and created active detector elements (more than 2000 scintillation detectors) that detect particle tracks.
- Proposed and developed a prototype 3D segmented scintillation detector for neutrino oscillation experiments. The detector prototype, consisting of 125 individual scintillation detectors, each with a volume of 1 cm³, was studied on the T10 channel (CERN). The parameters of the detector (light yield, temporal resolution) are obtained.
- Calibration of track solid-state detectors at the accelerator was carried out and the parameters of light ion tracks were measured. The results of the research are used in experiments on the study of cosmic radiation onboard the ISS (International Space Station). Analysis and comparison of different methods of scanning and measuring tracks in solid-state detectors using different sets of measured parameters is carried out; optimal approaches have been identified that make it possible to measure the absorbed energy along the tracks of secondary particles of cosmic radiation.
- The anisotropy of cosmic rays of ultrahigh energies was measured for the first time in groups of muons recorded by the coordinate track detector DECOR; the upper limits on the amplitudes of the dipole anisotropy are obtained: 1,6×10-3 for E > 1015 eV and 2.0×10-2 for E > 1016eV.
- A method for reconstructing the trajectories of primary cosmic rays for muons recorded on the Earth's surface has been developed. Trajectories for three locations of muon detectors are calculated: Apatity, Khabarovsk and Moscow for positive and negative polarity of the Sun.
- A complementary method of multicomponent studies of inclined broad atmospheric showers in the energy range 1015-1019 eV was developed. Using the PAMELA satellite experiment, Forbush studies of the decrease in the intensity of cosmic rays (the effect associated with the release of coronal mass during the development of active processes in the Sun) in a wide range of stiffness (0.4-20 GV) and for various components of the PCR (protons, helium nuclei and electrons); - it is shown that the recovery times for proton and helium nuclei of PCL in the Forbush effect coincide (6-10 days, depending on the rigidity of the particles) and are in good agreement with the theoretical models, while for the electronic component of the PCL, a significantly faster recovery time flow to steady mode (2-3 days at rigidity less than 2 GV); - the result does not fit into existing models and requires the creation of new models for describing the behavior of the electronic component of the PCL during Forbush depressions.
- Based on the analysis of regularities in the formation of the structure and texture of thin-walled pipes and repousse cells made of zirconium alloy, as well as the modeling of the stamping process, recommendations for optimizing the technology of manufacturing the cells of the distancing gratings of the fuel assemblies of the VVER-1000 reactor.
- As a result of the study of the layer-by-layer irregularity of hot-rolled sheets of ferritic steel used for the manufacture of pipes of main gas pipelines, the mechanism of deceleration of radial cracks in the pipes is revealed by creating a test gradient that promotes the branching of cracks.
- Experimentally demonstrated the possibility of using the modernized alloy-solder STEMET 1101M for the manufacture of divertor modules of European design for the thermonuclear facility of ITER by creating permanent tungsten-bronze compounds.
- A physical model of compacting of dispersed-strengthened ferritic-martensitic steels was developed, considering the mutual influence of the strengthening effect of Y2O3 nanoparticles on the matrix material, and softening effect in consequence of nanoparticles influence on amplification of heating of compact individual areas because of deformed of the distribution of electric current by the particles.
- A method for calculating the mutual rotation function of crystals using the quaternion presentation of the symmetry elements of cubic and hexagonal crystals is developed, the region of minimal rotations in the Eulerian motion space for cubic and hexagonal crystals is determined, and preliminary calculated data about the mutual rotation function are obtained accounting the position of the main maxima of the experimental orientation distribution functions for rolled products with a texture such as copper, silver, α-Fe and brass.
- Within the framework of cooperation with the Institute for Nuclear Research of the Russian Academy of Sciences (INR RAS), the research of the neutron component of the EAS on the world's first URAN facility established in 2016, which allows registering neutrons over the entire area of EAS. In 2017, the first data on the neutron spectrum, their spacial and temporal distributions were obtained.
- In 2017, within the framework of the agreement with the Geophysical Center of the Russian Academy of Sciences in the Institute of Nuclear Physics and Engineering (INPhE), the scientific project «Creation of a method for early diagnostics of geomagnetic storms on the basis of digital processing of time ranges of supervision matrices of a muon hodoscope» which will be performed till 2019. The project will be implemented until 2019. Directed at the development of a fundamentally new approach to the recognition of precursors of geomagnetic storms and early diagnostics of the associated extreme events in the helium- and magnetosphere, based on the system analysis of observational data of the muon hodoscope URAGAN.
- Within the framework of cooperation with IZMIRAN, studies of heliospheric disturbances caused by active processes on the Sun according to muon hodoscopes and neutron monitors were started, in 2018 an agreement is planned to jointly develop new approaches to the analysis of cosmic ray variations.
MOST SIGNIFICANT SCIENTIFIC RESULTS OF 2016
● Investigation of the emission of electrons from liquid xenon through the electroluminescence of the gas phase at the unique experimental facility RED-100 created in the INPhE laboratory and aimed at the search for the effect of elastic coherent scattering of neutrino on heavy nuclei.
● Development and manufacturing by the INPhE laboratory staff of the X-ray scanners for the system of control of the quality of production of the "New small wheels" detectors for the modernization of the ATLAS facility at CERN.
● Study of variation of the positron fraction in the total electron/positron flux during the 24th solar activity cycle in the “PAMELA” experiment at the “Resurs-DK1” spacecraft.
● Start of the program proposed by the MEPhI scientists for scanning energy of the incident beam of lead nuclei at the NA61/SHINE facility of the Proton Supersynchrotron at CERN.
● Creation of a miniature installation for studying properties and behavior of zirconium components of the core of light-water reactors (on thermal neutrons) in emergency situations.
Two leading international laboratories were included in the INPhE: the Interdepartmental Laboratory of Experimental Nuclear Physics and the Interdepartmental Laboratory of Prospective Technologies for the Creation of New Materials, as well as the Scientific and Educational Center NEVOD on the basis of which a unique world-class scientific facility operates.
A new International Research Laboratory "Physics of Atmospheric Processes" was opened on the basis of Scientific and Educational Center NEVOD in cooperation with the Yerevan Physics Institute (Armenia).
In addition, two new educational and scientific laboratories were opened in the INPhE: "Computer Engineering Simulation in the Field of Nuclear Technologies" and "Detectors of High-Energy Particles".
In 2016, to ensure the systematic training of design engineers of nuclear systems and equipment, a concept and plan of measures for the creation in 2017 of the "Higher Engineering School" which will concentrate educational programs on simulating, design and prototyping of complex technical systems were developed within the framework of INPhE.
- "Creation of experimental facilities and study of properties of matter under extreme conditions at the accelerator complexes of Mega-Science class";
- "Innovative directions of NPP safety improvement (fuel, materials, monitoring)";
- "Research of predictors of damaging processes and phenomena in the near-terrestrial space caused by the solar activity".
The developed projects are aimed at solving the following global scientific and technological tasks:
- study of the properties of matter under extreme conditions on femto-scales for the implementation of which it is necessary: to create the accelerator complex NICA, detector systems and cyberinfrastructure with the use of advanced and development of new technologies; to create the scientific and educational basis for the training of world-class specialists which will enable Russia to take the lead in studying fundamental properties of matter and creation of facilities of Mega-Science class (NICA, FAIR, RHIC, LHC);
- improving of the safety of nuclear power plants with the acceptable technical and economic indicators by creating the fuel resistant to accidents, continuous nuclear-physical monitoring of the core condition and prediction of degradation of properties of the reactor equipment materials during operation;
- comprehensive monitoring and forecasting of the development of potentially hazardous processes in the Earth's magnetosphere and atmosphere in order to minimize the risks and consequences of possible catastrophic phenomena.