The NUCLEON satellite experiment is designed to directly investigate the energy spectra of cosmic-ray nuclei and the chemical composition (Z = 1–30) in the energy range of 2–500 TeV. The experimental ...results are presented, including the energy spectra of different abundant nuclei measured using the new Kinematic Lightweight Energy Meter (KLEM) technique. The primary energy is reconstructed by registration of spatial density of the secondary particles. The particles are generated by the first hadronic inelastic interaction in a carbon target. Then additional particles are produced in a thin tungsten converter, by electromagnetic and hadronic interactions. The deconvolution of spectra was performed. Statistical errors were presented.
Data from the NUCLEON space observatory give a strong indication of the existence of a new universal cosmic ray “knee”, which is observed in all groups of nuclei, including heavy nuclei, near a ...magnetic rigidity of about 10 TV. Universality means the same position of the knee in the magnetic rigidity scale for all groups of nuclei. The knee is observed by both methods of measurement of particles energy implemented in the NUCLEON observatory—the calorimetric method and the kinematic method Kinematic Lightweight Energy Meter. This new cosmic ray knee is probably connected with the limit of acceleration of cosmic rays by some generic or nearby source of cosmic rays.
The article considers an electronic circuit that, in some cases, makes it possible to significantly reduce the number of readout channels in a silicon coordinate detector based on a matrix of
p–i–n
...structures (strip- or pad-type) without a loss in the coordinate measurement accuracy. The electronic circuit is a chain of external capacitors that connect the structures of the detector. When one of the structures is hit, a signal propagates along the chain of capacitors of the capacitive divider to the nearest readout channels and it is possible to determine the original number of the hit structure by the change in the signal value. The proposed circuit was mathematically simulated for typical parameters of the detector and readout electronics. The mathematical model allowed us to optimize the circuit parameters depending on the parameters of the detector and readout electronics. The simulation results are confirmed by experimental measurements on several prototypes of the device. It is shown that, in certain application cases, when a detector signal is high enough, e.g., when nuclei with
Z
> 6 are registered, one can achieve, by using standard low-noise operational amplifiers, the accurate recovery of the number of the hit structure in the chain consisting of at least 30 structures by reading only two extreme structures.
For a singularly perturbed reaction–diffusion equation, we study the structure of the internal transition layer in the case of a balanced reaction with a weak discontinuity. The existence of ...solutions with an internal transition layer (contrast structures) is proved, the question of their stability is investigated, and asymptotic approximations to solutions of this type are obtained. It is shown that in the case of reaction balance, the presence of even a weak (asymptotically small) reaction discontinuity can lead to the formation of contrast structures of finite size, both stable and unstable.
The aim of the NUCLEON space was to measure spectra of high-energy cosmic rays. The cosmic ray acceleration and propagation processes are determined by the magnetic rigidities of the particles. Thus ...the magnetic rigidity spectra of cosmic ray carbon and oxygen nuclei obtained by the NUCLEON experiment are analyzed and compared to some other experimental results. The spectral indices calculated for different thresholds with regard to magnetic rigidity are presented. The carbon and oxygen nuclei spectra are steeper than helium nuclei spectra in the 400-10000 GV area. The spectra of carbon and oxygen nuclei are similar to the proton spectrum before the “knee”.
The NUCLEON experiment was designed to study the chemical composition and energy spectra of galactic cosmic ray nuclei from protons to zinc at energies of ∼ 10{sup 11}–10{sup 15} eV per particle. The ...research was carried out with the NUCLEON scientific equipment installed on the Russian satellite 'Resource-P' No. 2 as an additional payload. This article presents the results for the measured nuclei spectra related to the first approximately 250 days of the scientific data collection during 2015 and 2016. The all-particle spectrum and the spectra of p, He, C, O, Ne, Mg, Si and Fe are presented. Some interesting ratios of the spectra are also presented and discussed. The experiment is now in its beginning stage and the data still have a preliminary character, but they already give numerous indications of the existence of various non-canonical phenomena in the physics of cosmic rays, which are expressed in the violation of a simple universal power law of the energy spectra. These features of the data are briefly discussed.
The High Energy Cosmic Ray Observatory (HERO) is an experimental design for the direct study of cosmic rays based on the use of an ultraheavy ionization calorimeter. The effective geometric factor of ...the facility will be at least 12 m
sr for cosmic-ray protons and at least 16–20 m
sr for nuclei and electrons. During 5–7 years of exposure, this mission will allow measuring the energy spectra of all common and rare cosmic-ray nuclei in the energy range of
eV/particle with element-by-element resolution of the charge of nuclei and with sufficiently high energy resolution. It is planned to study not only the cosmic ray nuclei with charges
, but also the superheavy nuclei beyond the iron peak, as well as high-energy electrons, positrons, and gamma rays. The main objectives, design appearance, and characteristics of the space mission are discussed.
A task of autonomous underwater vehicle (AUV) navigation is considered in the paper. The images obtained from an onboard stereo camera are used to build point clouds attached to a particular AUV ...position. Quantized SIFT descriptors of points are stored in a metric tree to organize an effective search procedure using a best bin first approach. Correspondences for a new point cloud are searched in a compact group of point clouds that have the largest number of similar descriptors stored in the tree. The new point cloud can be positioned relative to the other clouds without any prior information about the AUV position and uncertainty of this position. This approach increases the reliability of the AUV navigation system and makes it insensitive to data losses, textureless seafloor regions and long passes without trajectory intersections. Several algorithms are described in the paper: an algorithm of point clouds computation, an algorithm for establishing point clouds correspondence, and an algorithm of building groups of potentially linked point clouds to speedup the global search of correspondences. The general navigation algorithm consisting of three parallel subroutines: image adding, search tree updating, and global optimization is also presented. The proposed navigation system is tested on real and synthetic data. Tests on real data showed that the trajectory can be built even for an image sequence with 60% data losses with successive images that have either small or zero overlap. Tests on synthetic data showed that the constructed trajectory is close to the true one even for long missions. The average speed of image processing by the proposed navigation system is about 3 frames per second with a middle-price desktop CPU.
The aim of the NUCLEON space experiment was to measure spectra of high-energy cosmic rays. Direct measurements of energy spectra of protons and nuclei of cosmic rays which allow separating particles ...in charge are required to solve important astrophysical problems. The satellite was launched on December 26, 2014, and operated for three years. Measured spectra of protons and alpha particles in the energy range of 2–500 TeV per particle have been presented. The results have been analyzed and compared to other experimental data for lower energies. The ratio of fluxes of protons and alpha particles is nearly constant in a wide range of magnetic rigidities (3–100 TV). Thus, the behavior of the ratio of the spectra is significantly different from a similar dependence in the region of lower magnetic rigidities measured in other experiments. One of the possible explanation of this effect can be given within a model with one close source.
The DPS-NICA project has been developed to solve the urgent problem of measuring the radiation resistance of the electronic component base (ECB) of a spacecraft (SC) in outer space. To solve this ...problem, good coordinate resolution is required, which cannot be achieved without aligning the planes of the facility detectors. This article presents a methodology that allows it to be carried out based on experimental data.
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