The semi-classical approach to the calculating electromagnetic fields formed by interaction between hard radiation and matter is used to consider the passage of high-energy positrons through a gas ...medium. Results from calculating changes in electromagnetic fields in the optical range for air when high-energy positrons pass through it are presented.
We study one-dimensional flows of an ideal (inviscid and non-heat-conducting) perfect gas with an adiabatic exponent γ behind a shock wave moving toward the center (ν = 3) or axis (ν = 2) of symmetry ...in a cold gas at rest. Flows with a reflected shock wave and flows terminating with simultaneous arrival of a shock wave and a piston, which has compressed the gas into a point or line, to the center of symmetry are admitted.
Calculations are made for the angular distributions of changes in the energy of an electromagnetic field in the optical range formed by the interaction between high-energy electrons and a gas medium. ...The calculated values of the angular distributions are consistent with ones observed experimentally.
A way of calculating the angular distribution of changes in the energy of optical radiation generated by high-energy electrons passing through a solid transparent body is proposed that allows for the ...contribution from secondary electrons. The values are found of the angles at which peaks in optical radiation are observed when electrons pass through mica and glass.
Evaluation of the impact parameter in a single event of relativistic heavy ion collision is crucial for correct and efficient data processing and analysis. In this work we have studied the ...possibility of estimating the impact parameter in heavy ion collisions by using artificial neural networks applied to the charged particle data from fast microchannel plate (MCP) detectors. Charged particles’ multiplicity, their spatial distribution and time-of-flight data were used as event features to be analyzed by the artificial neural network algorithms. We investigated two different configurations of microchannel plate detector layout, that have different data and computational requirements. We have shown that the developed artificial neural networks technique is capable of providing sufficiently good and fast results on the impact parameter determination in a single heavy ion collision event for both configurations of MCP detectors layout. In our first exercises, the proposed algorithm has successfully identified more than 90
of Au
Au collision events with the impact parameter less than 5 fm or less than 1 fm, which suggests its use as a fast trigger.
Estimating the impact parameter in a single high-energy ion collision event is an important problem in data analysis in particle physics, because knowledge of the impact parameter is crucial for ...extracting information about the properties of nuclear matter. In this study, we present the use of a neural network approach for estimating the impact parameter and determining the collision class (head-on or peripheral collisions). We have modeled the data sourced from microchannel plate detectors in two geometries based on the
collision dataset at energies
GeV obtained by the QGSM MC event generator. We utilized the spatial distribution of particles and their time-of-flight data as event features. The addition of time-of-flight information improves the quality of impact parameter estimation. By comparing two detector geometries with different pseudorapidity acceptances (
and
), we demonstrated that a wider interval significantly enhances the results. The proposed algorithm was able to successfully classify more than 98
of
head-on collision events with an impact parameter of less than 5 fm and can be further useful as a fast trigger system. We also discuss further developments and improvements for possible applications of this technique in future experimental setups.
Based on the requisition for an ideal precise power source for a hybrid electric emergency rescue vehicle (HE-ERV), we present an optimistic parameter matching and optimization schemes for the ...selection of a HE-ERV. Then, given a set of optimized power source components, they are classified into different types of HE-ERV. In this study, due to the different design objectives of different types of emergency rescue vehicles and the problems of hybrid electric vehicle parameter matching, a multi-island genetic algorithm (MIGA) and non-linear programming quadratic Lagrangian (NLPQL) is proposed for the matched parameters. The vehicle dynamic model is established based on the AVL Cruise simulation platform. The power source performance parameters are matched by theoretical analysis and coupled to the simulation platform. Finally, the optimized matched parameters are classified based on the support vector machines classification model to determine the category of the HE-ERV. The classification results showed that there is an unprecedented level for categorizing several factors of the power source parameters. This research showed that its more logical and reasonable to match HE-ERVs with medium motor/engine power output and battery capacity, as these can attain dynamic performance, extended driving range, and reduced energy consumption.
A way of calculating the electromagnetic field generated by a narrow beam of gamma quanta passing through a gas medium is used to describe the field produced by the interaction between water and ...gamma radiation with an energy of 1 MeV. Variations in the electromagnetic field energy generated by secondary electrons are obtained as a function of the angle of observation.
The solutions of initial and boundary value problems of the outflow of an ideal (inviscid and non-heat-conducting) gas from cylindrical and spherical sources into a vacuum are obtained. Time is ...measured from the moment, when the source is turned on; at this moment the source is surrounded by a vacuum. The entropy, flow rate, and the Mach number of the gas outflowing from the source are given, together with the source radius; the Mach number can be greater of or equal to unity. If the source radius is greater than zero, then the flow domain in the “radial coordinate–time” plane consists of the stationary source flow and adjoining non-self-similar centered expansion wave consisting of
C
−
-characteristics. The stationary flow is described by the known formulas, while the expansion wave is calculated by the method of characteristics. The calculations by this method confirm the earlier obtained laws for large values of the radial coordinate. The interface between the vacuum and the expansion wave is the straight trajectory of particles and, at the same time, a unique rectilinear
C
−
-characteristic. For the source of zero radius (“pointwise” source) the velocity, density, and speed of sound of the outflowing gas are infinite. The gas velocity remains infinite everywhere, while the density and speed of sound become zero for any non-zero values of the radial coordinate. For the pointwise source the problem of outflow into a vacuum is self-similar. In the plane of the “self-similar” velocity and speed of sound its solution is given by three singular points of a differential equation in these variables. At one of these points the self-similar velocity is infinite, the self-similar speed of sound is zero, and the self-similar independent variable varies from zero to infinity, with the exception of the extreme values.
This paper presents multiplicity measurements of $K^0_S$, Λ, and $\bar{Λ}$ produced in 120 GeV/c proton-carbon interactions. The measurements were made using data collected at the NA61/SHINE ...experiment during two different periods. Decays of these neutral hadrons impact the measured π+, π-, p and $\bar{p}$ multiplicities in the 120 GeV/c proton-carbon reaction, which are crucial inputs for long-baseline neutrino experiment predictions of neutrino beam flux. The double-differential multiplicities presented here will be used to more precisely measure charged-hadron multiplicities in this reaction, and to reweight neutral hadron production in neutrino beam Monte Carlo simulations.
