Parameters of terahertz (THz) emission in two-dimensional (2D) tungsten diselenide (WSe
2
) film grown by chemical vapor deposition from the gas phase have been studied for the first time. The main ...mechanism of THz radiation generation in this system is established. Dependence of the THz signal amplitude on azimuthal angle in a 2D WSe
2
film has been studied. The distribution of the electric field of laser pumping in the WSe
2
/SiO
2
/Si structure has been calculated as dependent on the thickness of silicon dioxide layer. The choice of optimum structure geometry for effective generation of THz radiation by a WSe
2
monolayer is theoretically substantiated.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
A new Time-of-Flight (ToF) detector of the NA61/SHINE hadron spectrometer at CERN SPS based on Multigap Resistive Plate Chambers (MRPCs) technology is offered as a substitution of the scintillation ...ToF detector developed in 1990s. In 2019–2020, a prototype module of the new ToF system was tested on the 280 MeV/c positron beam to determine its characteristics. The analogue front-end electronics and DRS4-based waveform digitizer were used as a readout chain. This article presents the results of the MRPC test with analogue readout obtained in 2019–2020.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
—The results of developments of materials and structures used for generation and detection of terahertz radiation having applied photoconductive antennas are presented. The developments were carried ...out in three directions: optimization of parameters of nanoplasmonic antennas, formation of superlattice heterostructures based on InGaAs, and use of layered and two-dimensional semiconductors. The necessity and ways for further improvement in characteristics of the terahertz antennas for expanding the field of application of this radiation in spectroscopy of materials, biomedical diagnostics, metrology, spintronics, wireless communications, etc., are shown.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
A detector for adjusting the convergence of beams at the point of interaction of the MPD (multi-purpose detector) installation at the NICA collider (nuclotron-based ion collider facility) is ...discussed. Simulation of the detector operation for Au
Au collisions at
GeV is calculated. It is shown that background events from scattering on residual gas give a negligible contribution to the detector’s samples. It is discussed how to use a detector to adjust beam alignment. The calibration procedure for obtaining absolute luminosity in the MPD interaction zone with the help of this detector is considered.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
New NICA accelerator complex at JINR (Dubna), based on the existing upgraded Nuclotron accelerator, will allow conducting all types of research in the field of high-energy physics. The main tasks of ...this project are study of the properties of the deconfinement phase transition, experimental investigation on medium modification of vector mesons, and search for the QCD critical end point. Thus, two interaction points are foreseen in the NICA collider: one for studying the collision of heavy ions on the Multipurpose detector MPD, the other for polarized beams for the experiment on the SPD installation. The ambitious physical goals of MPD require excellent particle identification at the maximum possible range of phase space. Identification of charged hadrons is achieved by combining time-of-flight measurements and
energy loss measurements from the time-projection camera TPC. The Time-of-Flight system is based on multigap resistive plate chambers (MRPC), which are successfully used to identify particles in similar experiments around the world. A production site has been organized at the Laboratory of High Energy Physics of JINR for serial production of TOF MPD modules including 10 MRPCs. This site includes the entire cycle of work from preparing materials for the assembly of detectors to testing the assembled modules on cosmic radiation. This report presents the structure of the TOF system, its main parameters, the current state and the results of decoding and processing data obtained at the module testing facility.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Estimated counting rate in the collisions of heavy ions in the NICA/MPD are presented for collisions of main bunches (bunch-bunch scattering), satellite bunches (satellite-satellite scattering), and ...the collision of a main bunch with a satellite bunch (bunch-satellite scattering). The distribution of vertices in the MPD interaction area is presented. The main conclusion is that the contributions of satellite-satellite and satellite-bunch scattering do not exceed two percent of the bunch-bunch scattering.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
—
A new time-of-flight (ToF) system of the NA61/SHINE hadron spectrometer at the extracted beam of the Super Hadron Synchrotron in CERN has been developed in 2019–2022 by the staff of the Laboratory ...of High-Energy Physics of the Joint Institute for Nuclear Research. The new ToF system is based on Multigap Resistive Plate Chambers (MRPCs) technology. The previous system consisting of scintillation counters was substituted with the new ToF system. This paper presents the overview of the new NA61/SHINE ToF system.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
8.
Cold nuclear fusion Tsyganov, E.N.; Bavizhev, M.D.; Buryakov, M.G. ...
Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms,
07/2015, Volume:
355
Journal Article
Peer reviewed
If target deuterium atoms were implanted in a metal crystal in accelerator experiments, a sharp increase in the probability of DD-fusion reaction was clearly observed when compared with the ...reaction’s theoretical value. The electronic screening potential, which for a collision of free deuterium atoms is about 27eV, reached 300–700eV in the case of the DD-fusion in metallic crystals. These data leads to the conclusion that a ban must exist for deuterium atoms to be in the ground state 1s in a niche filled with free conduction electrons. At the same time, the state 2p whose energy level is only 10eV above that of state 1s is allowed in these conditions. With anisotropy of 2p, 3p or above orbitals, their spatial positions are strictly determined in the lattice coordinate system. When filling out the same potential niches with two deuterium atoms in the states 2p, 3p or higher, the nuclei of these atoms can be permanently positioned without creating much Coulomb repulsion at a very short distance from each other. In this case, the transparency of the potential barrier increases dramatically compared to the ground state 1s for these atoms. The probability of the deuterium nuclei penetrating the Coulomb barrier by zero quantum vibration of the DD-system also increases dramatically. The so-called cold nuclear DD-fusion for a number of years was registered in many experiments, however, was still rejected by mainstream science for allegedly having no consistent scientific explanation. Finally, it received the validation. Below, we outline the concept of this explanation and give the necessary calculations. This paper also considers the further destiny of the formed intermediate state of 4He∗.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Temperature dependences of electric field-induced and magnetic field-induced optical second harmonic generation (SHG) were used to study La
0.7
Ca
0.25
MnO
3
/BaTiO
3
(LCMO/BTO) superlattice. Ferroic ...properties of the superlattice are reveal by magnetic field-induced and electric field-induced SHG hysteresis loops ("magnetic" and "electric" SHG loops). However, direct modifications of the SHG hysteresis loops by the other field (electric field for the "magnetic loop" and vice versa) were not found. Strong modifications of the "electric" SHG hysteresis loops occur at temperatures close to the paramagnetic-ferromagnetic and the insulator-metal phase transitions in LCMO. In this way, the magnetoelectric interaction in an LCMO/BTO superlattice was established indirectly.
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BFBNIB, GIS, IJS, KISLJ, NUK, PNG, UL, UM, UPUK
