A microscopic study of spin-polarized 6Li atoms in highly elongated traps using the static fluctuation approximation (SFA)

2019 ◽  
Vol 571 ◽  
pp. 18-25
Author(s):  
Hyam Abdallah Al-Khzon ◽  
Mohamed Khaled Al-Sugheir
Keyword(s):  
Microscopic Study ◽  
Spin Polarized ◽  
Static Fluctuation Approximation ◽  
Static Fluctuation

SPIN-POLARIZED ATOMIC DEUTERIUM (↓D) IN THE STATIC FLUCTUATION APPROXIMATION (SFA)

2008 ◽  
Vol 22 (03) ◽  
pp. 257-266 ◽  
Author(s):  
A. S. SANDOUQA ◽  
B. R. JOUDEH ◽  
M. K. AL-SUGHEIR ◽  
H. B. GHASSIB
Keyword(s):  
Ground State Energy ◽  
Ground State ◽  
State Energy ◽  
Ideal Gas ◽  
Hard Sphere Model ◽  
Spin Polarized ◽  
Static Fluctuation Approximation ◽  
Static Fluctuation ◽  
Type Potential ◽  
The Ideal

Spin-polarized atomic deuterium (↓D) is investigated in the static fluctuation approximation with a Morse-type potential. The thermodynamic properties of the system are computed as functions of temperature. In addition, the ground-state energy per atom is calculated for the three species of ↓D : ↓D 1, ↓D 2, and ↓D 3. This is then compared to the corresponding ground-state energy per atom for the ideal gas, and to that obtained by the perturbation theory of the hard sphere model. It is deduced that ↓D is nearly ideal.

A microscopic study of neon and argon gases within the static fluctuation approximation (SFA)

2018 ◽  
Vol 32 (16) ◽  
pp. 1850203
Author(s):  
H. B. Ghassib ◽  
A. S. Sandouqa ◽  
B. R. Joudeh ◽  
I. F. Al-Maaitah ◽  
A. N. Akour ◽  
...  
Keyword(s):  
Experimental Data ◽  
Monte Carlo ◽  
Thermodynamic Properties ◽  
Specific Heat ◽  
Internal Energy ◽  
Microscopic Study ◽  
Ideal Gas ◽  
Static Fluctuation Approximation ◽  
Static Fluctuation ◽  
The Ideal

The thermodynamic properties of neon and argon gases are studied within the static fluctuation approximation (SFA). These properties include the total internal energy, pressure, entropy, compressibility and specific heat. The results are compared with those recently obtained within the Galitskii–Migdal–Feynman (GMF) formalism. The overall agreement is very good. An exception, however, is the specific-heat results for neon. While SFA gives results rather similar to those of the ideal gas, the corresponding GMF results are quite different. It is argued that the discrepancy seems to have arisen from quantum effects in conformity with very recent Monte Carlo computations. Whenever possible, our SFA results are compared to experimental data.

SPIN-POLARIZED ATOMIC HYDROGEN IN THE STATIC FLUCTUATION APPROXIMATION

2005 ◽  
Vol 19 (26) ◽  
pp. 3985-4008 ◽  
Author(s):  
B. R. JOUDEH ◽  
M. K. AL-SUGHEIR ◽  
H. B. GHASSIB
Keyword(s):  
Low Temperature ◽  
Spin Polarization ◽  
Temperature Region ◽  
Atomic Hydrogen ◽  
Unit Volume ◽  
Field Operator ◽  
Closed Set ◽  
Spin Polarized ◽  
Static Fluctuation Approximation ◽  
Static Fluctuation

In this paper we use the so-called static fluctuation approximation (SFA) to calculate the thermodynamic properties of spin-polarized atomic hydrogen. This approximation is based on the replacement of the square of the local-field operator with its mean value. A closed set of nonlinear integral equations is derived for neutral many-bosonic systems. This set is solved numerically by an iteration method for two triplet-state potentials: a Morse- and Silvera-type potentials. It is found that the mean internal energy per unit volume, the pressure, the entropy per unit volume, and the specific heat per unit volume increase with temperature and decrease with spin polarization in the low-temperature region (<8 mK ); whereas the condensate fraction increases with an applied magnetic field. It is also found that these quantities are nearly independent of spin polarization for high temperatures (>0.1 K ), and that they are independent of the number density up to 10-3Å-3 in the low-temperature region.

scholarly journals Влияние деформации на энергетический спектр и спектр оптического поглощения фуллерена C-=SUB=-20-=/SUB=- в модели Хаббарда

2019 ◽  
Vol 61 (2) ◽  
pp. 395
Author(s):  
А.В. Силантьев
Keyword(s):  
Group Theory ◽  
Hubbard Model ◽  
Symmetry Group ◽  
Energy Levels ◽  
Analytical Form ◽  
Symmetry Reduction ◽  
Energy Spectra ◽  
Symmetry Groups ◽  
Static Fluctuation Approximation ◽  
Static Fluctuation

Abstract —Anticommutator Green’s functions and energy spectra of fullerene C_20 with the I _ h , D _5 d , and D _3 d symmetry groups have been obtained in an analytical form within the Hubbard model and static fluctuation approximation. The energy states have been classified using the methods of group theory, and the allowed transitions in the energy spectra of fullerene C_20 with the I _ h , D _5 d , and D _3 d symmetry groups have been determined. It is also shown how the energy levels of fullerene C_20 with the I _ h symmetry group are split with the symmetry reduction.

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