scholarly journals Features of the distribution of events by the multiple of secondary particles depending on the energy of collision and the assymetricity of collising relativistic nuclei

2021 ◽  
Vol 78 (3) ◽  
pp. 80-87
Author(s):  
A.I. Fedosimova ◽  
◽  
I.A. Lebedev ◽  
E.A. Dmitriyeva ◽  
S.A. Ibraimova ◽  
...  
Keyword(s):  
Narrow Range ◽  
Initial Conditions ◽  
Linear Increase ◽  
Light Nuclei ◽  
Photographic Emulsion ◽  
Projectile Energy ◽  
Secondary Particles ◽  
Complete Destruction ◽  
Hadronic State ◽  
Favorable Conditions

To search for signals of the phase transition of matter from the hadronic state to the quark­gluon plasma, interactions with extreme characteristics are studied. The study of the dependence of the av­erage multiplicity on the projectile energy for sulfur and silicon nuclei with energies of 3.7 AGeV, 14 AGeV, and 200 AGeV has been carried out. Experimental data on inelastic interactions with the nuclei of the NIKFI BR­2 emulsion obtained at the SPS at CERN and at the Synchrophasotron at JINR. To take into account fluctuations in the initial conditions of the nucleus­nucleus interaction, the events were divided into central and peripheral ones. A comparative analysis of the average multiplicity with heavy and light nuclei of the photographic emulsion is presented. The multiplicity increase factor has an almost linear increase in energy (on the logarithmic axis) for all events, except for the central interactions of sulfur nuclei with heavy emulsion nuclei at 200 AGeV. These events are explosive events, which give a flux of secondary particles in a narrow range of average pseudo­rapidity and significantly shifted towards low values <η>. The analysis of events of complete destruction of the projectile nucleus is presented. Such events are considered as events in which the most favorable conditions are created for the formation of a quark­gluon plasma.

On the emission of fast ∑ -hyperons from disintegrations due to the capture of K - -mesons by light nuclei

1961 ◽  
Vol 262 (1308) ◽  
pp. 73-83 ◽  
Keyword(s):  
Light Nucleus ◽  
Light Nuclei ◽  
Photographic Emulsion ◽  
K Mesons

A study has been made of those disintegrations produced in photographic emulsion by the nuclear capture at rest of K - -mesons, from which fast charged ∑ -hyperons are emitted. In a sample of 63 events, six were analyzed unambiguously as being due to absorption in carbon, nitrogen or oxygen without the emission of any neutrons. An additional eight were found to be consistent with capture by a light nucleus with the emission of one neutron only in each case. The fraction of disintegrations due to K - -meson capture in light nuclei from which a fast charged ∑ -hyperon is emitted has been estimated.

scholarly journals The Optical Model and Proton Elastic Scattering from 14N and 16O

1977 ◽  
Vol 30 (3) ◽  
pp. 287 ◽  
Author(s):  
A Gabric ◽  
K Amos
Keyword(s):  
Elastic Scattering ◽  
Optical Model ◽  
Model Potential ◽  
Light Nuclei ◽  
Projectile Energy ◽  
Strength Parameters ◽  
Proton Elastic Scattering ◽  
Doorway State ◽  
Optical Model Potential

Allowing for important doorway state effects in analyses of proton elastic scattering from the light nuclei 14N and 160 enables an average geometry optical model potential to be determined, the strength parameters of which show a smooth behaviour with projectile energy.

Genesis of Tropical Storm Eugene (2005) from Merging Vortices Associated with ITCZ Breakdowns. Part III: Sensitivity to Various Genesis Parameters

2010 ◽  
Vol 67 (6) ◽  
pp. 1745-1758 ◽  
Author(s):  
Chanh Q. Kieu ◽  
Da-Lin Zhang
Keyword(s):  
Boundary Layer ◽  
Potential Vorticity ◽  
Initial Conditions ◽  
Tropical Storm ◽  
Cyclonic Vorticity ◽  
Merging Process ◽  
Continuous Potential ◽  
Frictional Convergence ◽  
Favorable Conditions ◽  
Vortex Merger

Abstract In this study, a series of sensitivity simulations is performed to examine the processes leading to the genesis of Tropical Storm Eugene (2005) from merging vortices associated with the breakdowns of the intertropical convergence zone (ITCZ) over the eastern Pacific. This is achieved by removing or modifying one of the two vortices in the model initial conditions or one physical process during the model integration using the results presented in Parts I and II as a control run. Results reveal that while the ITCZ breakdowns and subsequent poleward rollup (through a continuous potential vorticity supply) provide favorable conditions for the genesis of Eugene, the vortex merger is the most effective process in transforming weak tropical disturbances into a tropical storm. The sensitivity experiments confirm the authors’ previous conclusions that Eugene would not reach its observed tropical storm intensity in the absence of the merger and would become much shorter lived without the potential vorticity supply from the ITCZ. It is found that the merging process is sensitive not only to larger-scale steering flows but also to the intensity of their associated cyclonic circulations and frictional convergence. When one of the vortices is initialized at a weaker intensity, the two vortices bifurcate in track and fail to merge. The frictional convergence in the boundary layer appears to play an important role in accelerating the mutual attraction of the two vortices leading to their final merger. It is also found from simulations with different storm realizations that the storm-scale cyclonic vorticity grows at the fastest rate in the lowest layers, regardless of the merger, because of the important contribution of the convergence associated with the boundary layer friction and latent heating.

The angular distribution of secondary particles in high energy nuclear collisions with heavy nuclei of photographic emulsion

1960 ◽  
Vol 15 (1) ◽  
pp. 18-24 ◽  
Author(s):  
J. Bartke ◽  
P. Ciok ◽  
J. Gierula ◽  
R. Hołyński ◽  
M. Mięsowicz ◽  
...  
Keyword(s):  
Angular Distribution ◽  
High Energy ◽  
Photographic Emulsion ◽  
Heavy Nuclei ◽  
Nuclear Collisions ◽  
Secondary Particles

Characteristics of particle production in the interaction of 22.8 GeV/c protons with light nuclei in emulsion

1968 ◽  
Vol 46 (22) ◽  
pp. 2527-2532 ◽  
Author(s):  
B. Bhowmik ◽  
R. K. Shivpuri
Keyword(s):  
Angular Distribution ◽  
Transverse Momentum ◽  
Particle Production ◽  
Center Of Mass ◽  
Light Nuclei ◽  
High Multiplicity ◽  
Secondary Particles ◽  
Nucleon Interactions

The present work is aimed at the study of the characteristics of particle production in interactions between proton and light nuclei. The features studied are angular distribution, inelasticity, transverse momentum, and center-of-mass momentum of the secondary particles. In order to determine the contribution of multinucleon collisions, the results have been compared with those of proton–nucleon interactions. It has been found that, whereas the features of low-multiplicity events closely resemble the similar events from p–N collisions, those of high-multiplicity events are somewhat modified by the occurrence of intranuclear interactions.

Spin excitations in light nuclei: Effect of projectile energy

1989 ◽  
Vol 40 (1) ◽  
pp. 453-455 ◽  
Author(s):  
P. M. Boucher ◽  
B. Castel ◽  
Y. Okuhara
Keyword(s):  
Light Nuclei ◽  
Projectile Energy ◽  
Spin Excitations

scholarly journals Increasing the Quality of Transient Processes in the Vehicle Transmission

2019 ◽  
Vol 18 (6) ◽  
pp. 509-518
Author(s):  
A. Taratorkin ◽  
V. Derzhankii ◽  
I. Taratorkin
Keyword(s):  
Dynamic Loading ◽  
Response Rate ◽  
Initial Conditions ◽  
Simulation Models ◽  
Linear Increase ◽  
Transient Processes ◽  
Kinematic Alignment ◽  
Control Input ◽  
Single Node

The paper shows results of an experimental and theoretical study of dynamic processes in the vehicle transmission after kinematic alignment of elements during gearshifts. The purpose of the research is increasing the quality of transient processes in the vehicle transmission. Applying an analysis of experimental results obtained through looking into dynamics of a 3-ton vehicle transmission and studying literature sources it was established that dynamic loading of the transmission after the kinematic stage of shifting (i. e. synchronizing speeds of driving and driven elements in the gearbox) is influenced by oscillations which are in the single-node mode. Solving the task of increasing transient processes is achieved by applying a method of control power redistribution. By employing simulation models a number of methods were used to regulate power redistribution. Results of computations made it possible to determine that the efficiency of power redistribution are closely related to initial conditions of the process under the study. In the progress of the research a method for identifying the initial conditions was developed. This method is based determining signatures of the torque and its derivatives. In accordance with the research results it turned out that it is appropriate to apply the ZVD (zero vibration derivation) algorithm of power redistribution for low gears (below 4th) from point of view achieving better overshoot and robustness characteristics and a satisfactory response rate level. For higher gears it is recommended that the Ramp algorithm (linear increase in the control input) be used for the cases when the response rate is not longer than period of the single-node mode of oscillations occurring in the dynamic system during a gear shift. Application of the proposed algorithms allows to bring down dynamic loading of the transmission and also to improve the comfort in vehicles.

scholarly journals Influence of homogenization preceding to cold-rolling on the microstructure of the AA-3003

Ingenius ◽  
2021 ◽  
pp. 99-111
Author(s):  
Gennifer Aparicio-Carrillo ◽  
Marco Ciaccia-Sortino ◽  
Ricardo Jerez G.
Keyword(s):  
Cold Working ◽  
Initial Conditions ◽  
Casting Process ◽  
Direct Chill ◽  
Secondary Phases ◽  
Minor Variation ◽  
Backscattered Electrons ◽  
Secondary Particles ◽  
Primary Particles ◽  
Mn Content

The aluminum alloy AA3003 produced by a direct chill continuous casting process has a microstructure that significantly affects its potential use in engineering applications. This work studies the effects of the homogenizing heat treatment on the microstructure of AA3003 with cold working. Six conditions were studied, combining the variables initial condition (with and without homogenizing) and amount of cold working. All conditions were evaluated by means of optical and scanning electron microscopy, in combination with backscattered electrons and energy dispersive X ray spectroscopy techniques. Results suggest that for both initial conditions, the secondary phases present are Al6(Mn,Fe) and α-Al(Mn,Fe)Si, which vary in number, size, and shape. The homogenization caused the dissolution and precipitation of dispersoids, in addition to the spheroidization of primary particles, and minor variation of the size of secondary particles during cold working. Secondary phases are composed of primary and secondary particles, which differ in their Fe and Mn content, resulting in a lower Mn/Fe ratio for the primary particles (0,57 for the as‑received condition and 0,80 for the homogenized condition), whereas the dispersoids have a higher Mn/Fe ratio (1,56 after the homogenization). Homogenization increased ductility and reduced the likelihood of cracking during cold working. This was evidenced by the results obtained for strength, hardness, and ductility.

scholarly journals Search and Measurement of P-Odd Asymmetry in the Emission of Secondary Particles Produced in Reactions of Polarized Thermal and Cold Neutrons with Light Nuclei

2021 ◽  
Vol 52 (1) ◽  
pp. 1-18
Author(s):  
V. A. Vesna ◽  
Yu. M. Gledenov ◽  
V. V. Nesvizhevsky ◽  
P. V. Sedyshev ◽  
E. V. Shulgina
Keyword(s):  
Light Nuclei ◽  
Cold Neutrons ◽  
Secondary Particles
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