The RED-100 experiment Akimov, D.Yu; Alexandrov, I.S.; Alyev, R.R. ...
Journal of instrumentation,
11/2022, Letnik:
17, Številka:
11
Journal Article
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Abstract
The RED-100 two-phase xenon emission detector has been
deployed at 19-m distance from the reactor core of the Kalinin
Nuclear Power Plant (KNPP) in 2021–2022 for investigation of the
...possibility to observe reactor antineutrinos using the effect of
coherent elastic neutrino-nucleus scattering (CE
ν
NS). The
performance of the main systems of the RED-100 setup at operating
nuclear power plant is described. There is no correlation of the
radioactive background at the experimental setup site with ON and
OFF states of the reactor. The data taking run was carried out at
the beginning of the year 2022 and covered both the reactor OFF and
ON periods.
The concept of high refractive index subwavelength dielectric nanoresonators, supporting electric and magnetic optical resonance, is a promising platform for waveguiding, sensing, and nonlinear ...nanophotonic devices. However, high concentration of defects in the nanoresonators diminishes their resonant properties, which are crucially dependent on their internal losses. Therefore, it seems to be inevitable to use initially crystalline materials for fabrication of the nanoresonators. Here, we show that the fabrication of crystalline (low-loss) resonant silicon nanoparticles by femtosecond laser ablation of amorphous (high-loss) silicon thin films is possible. We apply two conceptually different approaches: recently proposed laser-induced transfer and a novel laser writing technique for large-scale fabrication of the crystalline nanoparticles. The crystallinity of the fabricated nanoparticles is proven by Raman spectroscopy and electron transmission microscopy, whereas optical resonant properties of the nanoparticles are studied using dark-field optical spectroscopy and full-wave electromagnetic simulations.
Crystalline (low-loss) resonant silicon nanoparticles have been fabricated by femtosecond laser ablation of amorphous (high-loss) silicon thin films using two conceptually different approaches.
Abstract
The RED-100 experiment with a liquid xenon target was
carried out at Kalinin Nuclear Power Plant. The goal of the
experiment is the detection and study of the coherent elastic
neutrino ...nucleus scattering process (CEνNS) for the low-energy
antineutrinos in close vicinity to a reactor core. A good
understanding of the external radioactive background is needed to
achieve this goal. This paper describes the external background
conditions for the RED-100 experiment at Kalinin Nuclear Power
Plant.
An array of cross-point memristive devices has been implemented on the basis of yttria-stabilized zirconia thin film for applications in prototypes of spiking neural networks. The resistive switching ...phenomena and the plasticity nature of such memristive devices are studied. Reproducible bipolar resistive switching and precise tuning of resistive state are demonstrated and used to implement the plasticity rule according to STDP (spike-timing-dependent plasticity) mechanism. STDP learning is found to be dependent on the memristor's initial resistive state value and discussed in terms of the finite conductance change in studied structures. Obtained results provide the foundation for autonomous neuromorphic circuits with unsupervised learning development.
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•An array of YSZ based cross-point memristors has been implemented for neuromorphic applications.•Resistive switching phenomenon and plasticity nature of YSZ based memristors are studied.•Spike-timing-dependent plasticity is shown to occur in the YSZ based memristors.
We investigate the constructive role of an external noise signal, in the form of a low-rate Poisson sequence of pulses supplied to all inputs of a spiking neural network, consisting in maintaining ...for a long time or even recovering a memory trace (engram) of the image without its direct renewal (or rewriting). In particular, this unique dynamic property is demonstrated in a single-layer spiking neural network consisting of simple integrate-and-fire neurons and memristive synaptic weights. This is carried out by preserving and even fine-tuning the conductance values of memristors in terms of dynamic plasticity, specifically spike-timing-dependent plasticity-type, driven by overlapping pre- and postsynaptic voltage spikes. It has been shown that the weights can be to a certain extent unreliable, due to such characteristics as the limited retention time of resistive state or the variation of switching voltages. Such a noise-assisted persistence of memory, on one hand, could be a prototypical mechanism in a biological nervous system and, on the other hand, brings one step closer to the possibility of building reliable spiking neural networks composed of unreliable analog elements.
The stochastic resonance phenomenon has been studied experimentally and theoretically for a state-of-art metal-oxide memristive device based on yttria-stabilized zirconium dioxide and tantalum ...pentoxide, which exhibits bipolar filamentary resistive switching of anionic type. The effect of white Gaussian noise superimposed on the sub-threshold sinusoidal driving signal is analyzed through the time series statistics of the resistive switching parameters, the spectral response to a periodic perturbation and the signal-to-noise ratio at the output of the nonlinear system. The stabilized resistive switching and the increased memristance response are revealed in the observed regularities at an optimal noise intensity corresponding to the stochastic resonance phenomenon and interpreted using a stochastic memristor model taking into account an external noise source added to the control voltage. The obtained results clearly show that noise and fluctuations can play a constructive role in nonlinear memristive systems far from equilibrium.
Magnesium alloys are commonly used to produce lightweight parts. While most magnesium alloys exhibit low thermal conductivities, high thermal conductivities are needed for electronic devices. In this ...study, we attempted to develop new magnesium casting alloys with high thermal conductivities. The MgZnSiCa alloy compositions were chosen using CALPHAD (CALculation of PHAse Diagrams) calculations, and alloy samples were prepared. The fluidity and hot-tearing resistance were measured. The results indicated that these properties were similar to those of AZ91 alloy. Tensile tests showed that high-pressure die casting could produce MgZnSiCa alloys possessing mechanical properties 1.5–3 times higher than those produced via sand casting. The alloy thermal conductivity was 126 W/mK at room temperature. The corrosion rates of the as-cast samples in NaCl/water solutions were two times higher than that of AZ91. Keywords: Magnesium alloy, Thermal conductivity, Phase composition, Corrosion rate, Sand casting, High-pressure die casting
We propose a stochastic model for a memristive system by generalizing known approaches and experimental results. We validate our theoretical model by experiments carried out on a memristive device ...based on multilayer structure. In the framework of the proposed model we obtain the exact analytic expressions for stationary and nonstationary solutions. We analyze the equilibrium and non-equilibrium steady-state distributions of the internal state variable of the memristive system and study the influence of fluctuations on the resistive switching, including the relaxation time to the steady-state. The relaxation time shows a nonmonotonic dependence, with a minimum, on the intensity of the fluctuations. This paves the way for using the intensity of fluctuations as a control parameter for switching dynamics in memristive devices.
The cross sections of J/ψ ηc and J/ψ J/ψ production in e+ e− annihilation are calculated at a one-loop accuracy near Z -boson pole and at higher energies as well. Both intermediate bosons, γ and Z ..., are included. It is found that at Z mass, the next-to-leading contribution increases the production cross sections by a factor of 3.5.
The article reports a review of the current results obtained over the past decade in the study of cosmic ray solar modulation. The analysis of modulation effects was carried out in the isotropic and ...anisotropic approximations on the data of the ground-based network of detectors and the first data from the PAMELA and AMS-02 magnetic spectrometers. In the isotropic approximation, we consider the spectrum of CR variations and its transformation, caused by the change in the polarity of the Sun general magnetic field. The latest empirical models of long-term variations are reviewed. Long-term variations in the amplitude and phase of the solar-diurnal variation of north–south cosmic rays anisotropy are considered in the anisotropic approximation. Comparison and calibration of the ground-based monitoring results with the data from magnetic spectrometers PAMELA, AMS-02 are carried out.
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