scholarly journals Collective Oscillations in Many Electron Atoms. II. Scattering and Slowing Down

1974 ◽  
Vol 27 (2) ◽  
pp. 169
Author(s):  
JJ Monaghan
Keyword(s):  
Charged Particle ◽  
Charged Particles ◽  
Fermi Model ◽  
Thomas Fermi ◽  
Slowing Down ◽  
Wide Range ◽  
Collective Oscillations

The slowing down of fast charged particles by their interaction with many electron atoms is considered using the hydrodynamic version of the Thomas-Fermi model. The agreement obtained with experiment is excellent over a wide range of parameters but worsens as the velocity of the charged particle decreases.

scholarly journals Collective Oscillations in Many Electron Atoms. I. Eigenvalues and Polarization

1973 ◽  
Vol 26 (5) ◽  
pp. 597 ◽  
Author(s):  
JJ Monaghan
Keyword(s):  
Oscillator Strengths ◽  
Neutral Atoms ◽  
Fermi Model ◽  
Thomas Fermi ◽  
Classical Oscillator ◽  
Static Polarization ◽  
Collective Oscillations

Following the work of Bloch, the Thomas-Fermi model is extended to collective oscillations. The eigenfunctions and frequencies for radial and nonradial I = 1 modes are found. The calculated static polarization is compared with experiment, both for ions and neutral atoms, and the classical oscillator strengths are computed.

CONSTANT-PHASE-INDUCED CONTROL OF CHAOTIC CHARGED PARTICLES IN THE FIELD OF A WAVE PACKET

2013 ◽  
Vol 23 (06) ◽  
pp. 1330022
Author(s):  
RICARDO CHACÓN
Keyword(s):  
Charged Particle ◽  
Wave Packet ◽  
Finite Number ◽  
Lyapunov Exponents ◽  
Chaotic Dynamics ◽  
Chaotic Behavior ◽  
Charged Particles ◽  
Melnikov Method ◽  
Wide Range ◽  
Range Of Values

It is shown that the dissipative chaotic dynamics of a charged particle in the field of a wave packet with an arbitrary but finite number of harmonics can be reliably suppressed by judiciously varying the constant phase of the main harmonic, ϕ0, while keeping null the corresponding constant phases of the remaining harmonics. The dependence of the chaotic threshold on the wave packet parameters is predicted theoretically (Melnikov method) and confirmed numerically (Lyapunov exponents). In particular, it is shown that ϕ0 is effective at suppressing the chaotic behavior existing when ϕ0 = 0 over a wide range of values of the wave packet width, while the remaining parameters are kept constant.

The Thomas-Fermi model in the theory of systems of charged particles above the surface of liquid dielectrics

2012 ◽  
Vol 53 (10) ◽  
pp. 103302 ◽  
Author(s):  
D. M. Lytvtnenko ◽  
Yu. V. Slyusarenko ◽  
A. I. Kirdin
Keyword(s):  
Charged Particles ◽  
Fermi Model ◽  
Thomas Fermi ◽  
Liquid Dielectrics

scholarly journals Multiplicity dependence of (multi-)strange hadron production in proton-proton collisions at $$\sqrt{s}$$ = 13 TeV

2020 ◽  
Vol 80 (2) ◽  
Author(s):  
S. Acharya ◽  
◽  
D. Adamová ◽  
S. P. Adhya ◽  
A. Adler ◽  
...  
Keyword(s):  
Charged Particle ◽  
Charged Particles ◽  
General Purpose ◽  
Particle Multiplicity ◽  
Charged Particle Multiplicity ◽  
Production Rates ◽  
Proton Proton ◽  
Proton Collisions ◽  
Strange Hadron ◽  
Proton Proton Collisions

Abstract The production rates and the transverse momentum distribution of strange hadrons at mid-rapidity ($$\left| y\right| < 0.5$$y<0.5) are measured in proton-proton collisions at $$\sqrt{s}$$s = 13 TeV as a function of the charged particle multiplicity, using the ALICE detector at the LHC. The production rates of $$\mathrm{K}^{0}_{S}$$KS0, $$\Lambda $$Λ, $$\Xi $$Ξ, and $$\Omega $$Ω increase with the multiplicity faster than what is reported for inclusive charged particles. The increase is found to be more pronounced for hadrons with a larger strangeness content. Possible auto-correlations between the charged particles and the strange hadrons are evaluated by measuring the event-activity with charged particle multiplicity estimators covering different pseudorapidity regions. When comparing to lower energy results, the yields of strange hadrons are found to depend only on the mid-rapidity charged particle multiplicity. Several features of the data are reproduced qualitatively by general purpose QCD Monte Carlo models that take into account the effect of densely-packed QCD strings in high multiplicity collisions. However, none of the tested models reproduce the data quantitatively. This work corroborates and extends the ALICE findings on strangeness production in proton-proton collisions at 7 TeV.

Comparison of Variational Solutions of the Thomas-Fermi Model in Terms of the Corrected Ionization Energy

1987 ◽  
Vol 42 (9) ◽  
pp. 943-947
Author(s):  
I. Agil ◽  
A. Alharkan ◽  
H . Alhendi ◽  
A. Alnaghmoosh
Keyword(s):  
Ionization Energy ◽  
Trial Function ◽  
Binding Energies ◽  
Initial Slope ◽  
Fermi Model ◽  
Thomas Fermi ◽  
Variational Solutions ◽  
Comparison Of The Results

It is shown that leading corrections, to the ionization energy, of many-electrons atom, can be expressed as leading corrections of initial slope of trial variational solutions of the Thomas-Fermi equation. Some variational solutions with different initial slopes are compared. A comparison of the results shows, that as far as the binding energies are concerned a trial function with its slope not close to the (negative) Baker’s constant may not be suited.

On sodium clusters in C60 fullerides

1997 ◽  
Vol 75 (1) ◽  
pp. 77-82 ◽  
Author(s):  
M. Apostol ◽  
F. Rachdi ◽  
C. Goze ◽  
L. Hajji
Keyword(s):  
Electric Charge ◽  
The Body ◽  
Electron Charge ◽  
Body Centered Cubic ◽  
Fermi Theory ◽  
Fermi Model ◽  
Thomas Fermi ◽  
Sodium Clusters ◽  
Alkali Fullerides

Sodium (Na) clusters in octahedral cages of Na-intercalated fullerides Na6C60 and Na11C60 are studied within a Thomas–Fermi model. It is shown that the tetrahedral Na4 cluster in Na6C60 has an electric charge ~ +2.7 (in electron charge units), while the body-centered cubic Na9 cluster in Na11C60 is almost electrically neutral. Keywords: sodium clusters, alkali fullerides, Thomas–Fermi theory, ionization charge.

EFFECT OF NEGATIVELY-CHARGED MASSIVE PARTICLES ON BIG-BANG NUCLEOSYNTHESIS AND A SOLUTION TO THE LITHIUM PROBLEMS

2008 ◽  
Vol 23 (17n20) ◽  
pp. 1668-1674
Author(s):  
MOTOHIKO KUSAKABE ◽  
TOSHITAKA KAJINO ◽  
RICHARD N. BOYD ◽  
TAKASHI YOSHIDA ◽  
GRANT J. MATHEWS
Keyword(s):  
Charged Particle ◽  
Nuclear Reactions ◽  
Charged Particles ◽  
Big Bang ◽  
Light Nuclei ◽  
Big Bang Nucleosynthesis ◽  
Spectroscopic Observations ◽  
Halo Stars ◽  
Wmap Data ◽  
Ionization Processes

Spectroscopic observations of metal poor halo stars give an indication of a possible primordial plateau of 6 Li abundance as a function of metallicity similar to that for 7 Li . The inferred abundance of 6 Li is ~1000 times larger than that predicted by standard big bang nucleosynthesis (BBN) for the baryon-to-photon ratio inferred from the WMAP data, and that of 7 Li is about 3 times smaller than the prediction. We study a possible solution to both the problems of underproduction of 6 Li and overproduction of 7 Li in BBN. This solution involves a hypothetical massive, negatively-charged particle that would bind to the light nuclei produced in BBN. The particle gets bound to the existing nuclei after the usual BBN, and a second epoch of nucleosynthesis can occur among nuclei bound to the particles. We numerically carry out a fully dynamical BBN calculation, simultaneously solving the recombination and ionization processes of negatively-charged particles by normal and particle-bound nuclei as well as many possible nuclear reactions among them. It is confirmed that BBN in the presence of these hypothetical particles can solve the two Li abundance problems simultaneously.

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