scholarly journals Shower and Slow Particle Productions in Nucleus-Nucleus Collisions at High Energy

2014 ◽  
Vol 2014 ◽  
pp. 1-12 ◽  
Author(s):  
S. Fakhraddin ◽  
Magda A. Rahim ◽  
Hamdy M. M. Zayd
Keyword(s):  
Experimental Data ◽  
Thermal Model ◽  
Theoretical Calculations ◽  
High Energy ◽  
Experimental Results ◽  
Angular Distributions ◽  
Target Groups ◽  
Slow Particle ◽  
Multiplicity Distributions

The multiplicity distributions of shower, grey, and black particles produced in interactions of4He,12C,16O,22Ne, and28Si with emulsion (Em) at 4.1–4.5 A GeV/c beam energies, and their dependence on target groups (H, CNO, and AgBr) is presented and has been reproduced by multisource thermal model. The multiplicity and the angular distributions of the three types of particles have been investigated. The experimental results are compared with the corresponding ones from the model. We found that the experimental data agrees with theoretical calculations using multisource thermal model.

ANGULAR DISTRIBUTIONS OF TARGET BLACK FRAGMENTS IN NUCLEUS–NUCLEUS COLLISIONS AT HIGH ENERGY

2003 ◽  
Vol 12 (05) ◽  
pp. 713-723 ◽  
Author(s):  
FU-HU LIU ◽  
NABIL N. ABD ALLAH ◽  
DONG-HAI ZHANG ◽  
MAI-YING DUAN
Keyword(s):  
Experimental Data ◽  
Monte Carlo ◽  
High Energy ◽  
Ideal Gas ◽  
Experimental Results ◽  
Angular Distributions ◽  
Ideal Gas Model

The experimental results of space, azimuthal, and projected angular distributions of target black fragments produced in silicon-emulsion collisions at 4.5A GeV/c (the Dubna energy) are reported. A multi-source ideal gas model is suggested to describe the experimental angular distributions. The Monte Carlo calculated results are in agreement with the experimental data.

SOME CHARACTERISTICS OF THE COMPOUND MULTIPLICITY IN HIGH-ENERGY NUCLEUS–NUCLEUS INTERACTIONS

2011 ◽  
Vol 20 (08) ◽  
pp. 1735-1754 ◽  
Author(s):  
M. MOHERY ◽  
M. ARAFA
Keyword(s):  
Experimental Data ◽  
Impact Parameter ◽  
Mass Number ◽  
Multiplicity Distribution ◽  
High Energy ◽  
Projectile Nucleus ◽  
Target Mass ◽  
Compound Multiplicity ◽  
Multiplicity Distributions ◽  
The Impact

The present paper deals with the interactions of 22 Ne and 28 Si nuclei at (4.1–4.5)A GeV /c with emulsion. Some characteristics of the compound multiplicity nc given by the sum of the number of shower particles ns and grey particles ng have been investigated. The present experimental data are compared with the corresponding ones calculated according to modified cascade evaporation model (MCEM). The results reveal that the compound multiplicity distributions for these two reactions are consistent with the corresponding ones of MCEM data. It can also be seen that the peak of these distributions shifts towards a higher value of nc with increasing projectile mass. It may further be seen that the compound multiplicity distributions becomes broader with increasing target size and its width increases with the size of the projectile nucleus. In addition, it has been found that the MCEM can describe the compound multiplicity characteristics of the different projectile, target and the correlation between different emitted particles. The values of average compound multiplicity increase with increasing mass of the projectile. Furthermore, it is observed that while the value of 〈nc〉 depends on the mass number of the projectile Ap and the target mass number At, the value of the ratio 〈nc〉/D(nc) seems to be independent of Ap and At. The impact parameter is found to affect the shape of the compound multiplicity distribution. Finally, the dependence of the average compound multiplicity on the numbers of grey and black particles, and the sum of them, is obvious. The values of the slope have been found to be independent of the projectile nucleus.

SYSTEMATIC COMPARISON OF THE EXPERIMENTAL DATA WITH THE FRITIOF MODEL IN NUCLEUS–NUCLEUS INTERACTIONS WITH LIGHT AND HEAVY TARGET NUCLEI IN NUCLEAR EMULSION AT 4.5A Gev/c

2002 ◽  
Vol 11 (02) ◽  
pp. 161-175 ◽  
Author(s):  
M. MOHERY ◽  
N. N. ABD-ALLAH
Keyword(s):  
Experimental Data ◽  
Nuclear Emulsion ◽  
Multiplicity Distribution ◽  
Angular Distributions ◽  
Target Groups ◽  
Systematic Comparison ◽  
Secondary Particles ◽  
Heavy Target ◽  
Light Target ◽  
Fritiof Model

The characteristics of the interactions of 4.5 A GeV/c 28 Si nuclei with emulsion have been investigated. The method of separating interactions into those with hydrogen, light and heavy target nuclei has been discussed. The multiplicity distribution, average multiplicities, multiplicity correlation and the angular distributions of the secondary particles emitted in 28 Si -emulsion are calculated according to the Modified Fritiof Model and compared with the experimental data and with other available data for p, 12 C , 24 Mg at the same energy. It has been found that the modified Fritiof model can describe the multiplicity characteristics of the different emitted particles in the above-mentioned interaction with different target groups. The comparison of the experimental data with the modified Fritiof model shows no clear preference for the case of the light target while it seems to be nearer to the experimental data in the case of the heavy target and the emulsion

Young’s Experiment on Slits with an Angle Between Them

2014 ◽  
Vol 9 (2) ◽  
pp. 173-179
Author(s):  
Anton Bogomyagkov ◽  
Viktor Dorokhov ◽  
Oleg Meshkov ◽  
Aleksandr Polygalov ◽  
Alexey Shcheglov
Keyword(s):  
Experimental Data ◽  
Interference Pattern ◽  
Intensity Distribution ◽  
Mathematical Analysis ◽  
Theoretical Calculations ◽  
Experimental Results ◽  
Digital Data ◽  
Hyperbolic Function ◽  
Standard Laboratory ◽  
Arbitrary Angle

Here are proposed a modified version of Young’s experiment on slits with an arbitrary angle between them. Also here performed mathematical analysis of the proposed scheme, showing that the intensity distribution can be approximated by a hyperbolic function. Experimental data confirm theoretical calculations. Analysis of the experimental results has conducted using two different methods of processing the digital data of the interference pattern. Theoretical calculations and experimental results established a nontrivial fact, that the interference patterns for slits with different, but symmetrical respect to 90° angles have the same intensity distribution. This experiment may be used as a standard laboratory work in University on optics workshop

Tsallis nonextensive entropy and the multiplicity distributions in high energy leptonic collisions

2016 ◽  
Vol 25 (06) ◽  
pp. 1650041 ◽  
Author(s):  
S. Sharma ◽  
M. Kaur ◽  
Sandeep Kaur
Keyword(s):  
Experimental Data ◽  
Multiplicity Distribution ◽  
High Energy ◽  
New Approach ◽  
High Energies ◽  
Nonextensive Entropy ◽  
Tsallis Distribution ◽  
Multiplicity Distributions ◽  
Better Than

The nonextensive behavior of entropy is exploited to explain the regularity in multiplicity distributions in [Formula: see text] collisions at high energies. The experimental data are analyzed by using Tsallis [Formula: see text]-statistics. We propose a new approach of applying Tsallis [Formula: see text]-statistics, wherein the multiplicity distribution is divided into two components; two-jet and multijet components. A convoluted Tsallis distribution is fitted to the data. It is shown that this method gives the best fits which are several orders better than the conventional fit of Tsallis distribution.

scholarly journals Laboratory radiative accretion shocks on GEKKO XII laser facility for POLAR project

2018 ◽  
Vol 6 ◽  
Author(s):  
L. Van Box Som ◽  
É. Falize ◽  
M. Koenig ◽  
Y. Sakawa ◽  
B. Albertazzi ◽  
...  
Keyword(s):  
Experimental Data ◽  
Laser Energy ◽  
High Energy ◽  
Experimental Results ◽  
Material Structure ◽  
Reverse Shock ◽  
Before And After ◽  
Laser Facility ◽  
Post Shock ◽  
Accretion Shocks

A new target design is presented to model high-energy radiative accretion shocks in polars. In this paper, we present the experimental results obtained on the GEKKO XII laser facility for the POLAR project. The experimental results are compared with 2D FCI2 simulations to characterize the dynamics and the structure of plasma flow before and after the collision. The good agreement between simulations and experimental data confirms the formation of a reverse shock where cooling losses start modifying the post-shock region. With the multi-material structure of the target, a hydrodynamic collimation is exhibited and a radiative structure coupled with the reverse shock is highlighted in both experimental data and simulations. The flexibility of the laser energy produced on GEKKO XII allowed us to produce high-velocity flows and study new and interesting radiation hydrodynamic regimes between those obtained on the LULI2000 and Orion laser facilities.

Systematic study of rapidity dispersion parameter in high energy nucleus–nucleus interactions

2014 ◽  
Vol 23 (03) ◽  
pp. 1450012 ◽  
Author(s):  
Swarnapratim Bhattacharyya ◽  
Maria Haiduc ◽  
Alina Tania Neagu ◽  
Elena Firu
Keyword(s):  
Experimental Data ◽  
Monte Carlo ◽  
Systematic Study ◽  
Nuclear Emulsion ◽  
Quantitative Measure ◽  
High Energy ◽  
Average Multiplicity ◽  
Experimental Results ◽  
Dispersion Parameter ◽  
Parameter Values

A systematic study of rapidity dispersion parameter as a quantitative measure of clustering of particles has been carried out in the interactions of 16 O , 28 Si and 32 S projectiles at 4.5 A GeV/c with heavy ( AgBr ) and light (CNO) groups of targets present in the nuclear emulsion. For all the interactions, the total ensemble of events has been divided into four overlapping multiplicity classes depending on the number of shower particles. For all the interactions and for each multiplicity class, the rapidity dispersion parameter values indicate the occurrence of clusterization during the multiparticle production at Dubna energy. The measured rapidity dispersion parameter values are found to decrease with the increase of average multiplicity for all the interactions. The dependence of rapidity dispersion parameter on the average multiplicity can be successfully described by a relation D(η) = a + b〈ns〉 + c〈ns〉2. The experimental results have been compared with the results obtained from the analysis of Monte Carlo simulated (MC-RAND) events. MC-RAND events show weaker clusterization among the pions in comparison to the experimental data.

Target productions in forward and backward hemispheres in the interactions of 28Si-EM at 14.6A GeV

2015 ◽  
Vol 24 (11) ◽  
pp. 1550084 ◽  
Author(s):  
A. Abdelsalam ◽  
M. S. El-Nagdy ◽  
A. M. Abdalla ◽  
A. Saber
Keyword(s):  
Experimental Data ◽  
Angular Distribution ◽  
Energy Dependence ◽  
Mass Number ◽  
Particle Production ◽  
Charged Particles ◽  
Experimental Results ◽  
Anisotropy Ratio ◽  
Nuclear Emulsions ◽  
Slow Particle

This paper search for the results and properties of slow particle productions, appear as a gray and black tracks in nuclear emulsions, producing secondary charged particles which are emitted from [Formula: see text]Si interactions with emulsion nuclei at 14.6[Formula: see text] GeV. The forward particles emission of interactions, ([Formula: see text]) as well as the backward ones ([Formula: see text]), have been investigated. It includes the effect of both projectile mass number and energy on the production and multiplicities of these particles. The results compared with other experiments for the same target but with different projectiles and energies. The experimental data show that there are two different mechanisms responsible for the production of gray particles for the chosen channels of emission angles and each are energy dependence. This dependence is weakly on the projectile mass number. The same investigations are applied for black tracks producing particles. The experimental results show the production of these particles is purely target fragments independent on both projectile mass number and its energy. The anisotropy ratio of angular distribution (F/B) is applied for both kinds of particles which are found the value for gray particle production depends on the direction of emissions while it is unchanged for black particles.

Studies of Asymmetric particle Production in Different Multiplicity Zone in Azimuthal Space in High Energy Nucleus-Nucleus Interactions

2020 ◽  
Author(s):  
Swarnapratim Bhattacharyya
Keyword(s):  
Experimental Data ◽  
Monte Carlo ◽  
Particle Production ◽  
High Energy ◽  
Experimental Results ◽  
Dynamical Fluctuations ◽  
Experimental Findings

Studies of asymmetric particle production and investigation of dynamical fluctuations in different multiplicity zone in azimuthal space are performed for <sup>16</sup>O-AgBr, <sup>22</sup>Ne-AgBr, <sup>28</sup>Si-AgBr and <sup>32</sup>S-AgBr interactions at (4.1-4.5) AGeV/c. Evidence of strong dynamical fluctuations is observed for the experimental data. Comparisons of the experimental results with the results of Monte Carlo simulated events (MC-RAND) and the results obtained from the analysis of AMPT model also strengthen the experimental findings.

ELASTIC SCATTERING AS A TEST OF DENSITY DISTRIBUTIONS IN 6He AND 8He

2002 ◽  
Vol 11 (03) ◽  
pp. 249-264 ◽  
Author(s):  
M. AVRIGEANU ◽  
G. S. ANAGNOSTATOS ◽  
A. N. ANTONOV ◽  
V. AVRIGEANU
Keyword(s):  
Experimental Data ◽  
Elastic Scattering ◽  
Imaginary Part ◽  
Optical Potential ◽  
Theoretical Calculations ◽  
Scattering Data ◽  
Angular Distributions ◽  
Helium Isotopes ◽  
Density Distributions ◽  
Good Agreement

Taking elastic scattering of 6,8 He on protons as an example, it is shown that the differences between density distributions coming from different models can be evaluated when scattering data of the nuclei involved are available for comparison. Microscopic elastic-scattering angular distributions have been calculated for incident energies <100A MeV by using the Tanihata and COSMA models for the density distributions of He nuclei, the M3Y-Paris effective NN interaction, and the Bray et al. imaginary part of the optical potential. The present microscopic angular distributions based on the Tanihata densities are in good agreement with the available experimental data and also similar to results of other theoretical calculations, showing the sensitivity of scattering to the density distributions of these helium isotopes.

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