t-quarkonian energy levels and the strong-interaction coupling constant

1986 ◽  
Vol 33 (1) ◽  
pp. 284-286 ◽  
Author(s):  
L. Clavelli ◽  
D. B. Lichtenberg ◽  
J. G. Wills
1977 ◽  
Vol 55 (10) ◽  
pp. 937-942 ◽  
Author(s):  
A. F. Leung ◽  
Ying-Ming Poon

The absorption spectra of UCl5 single crystal were observed in the region between 0.6 and 2.4 μm at room, 77, and 4.2 K temperatures. Five pure electronic transitions were assigned at 11 665, 9772, 8950, 6643, and 4300 cm−1. The energy levels associated with these transitions were identified as the splittings of the 5f1 ground configuration under the influence of the spin–orbit coupling and a crystal field of C2v symmetry. The number of crystal field parameters was reduced by assuming the point-charge model where the positions of the ions were determined by X-ray crystallography. Then, the crystal field parameters and the spin–orbit coupling constant were calculated to be [Formula: see text],[Formula: see text], [Formula: see text], and ξ = 1760 cm−1. The vibronic analysis showed that the 90, 200, and 320 cm−1 modes were similar to the T2u(v6), T1u(v4), and T1u(v3) of an UCl6− octahedron, respectively.


The study of collisions between nuclear particles has developed to a remarkable extent with the discovery of the neutron and the introduction of artificial methods for effecting nuclear disintegration. It has been found in the last few years that the interpretation of the observed results is by no means as simple as was first expected. This situation is most apparent when the explanation of the variation of probability of capture of slow neutrons by different nuclei is considered. This probability varies in a very irregular manner from element to element and pronounced selective effects occur in certain cases. Attempts to explain (Elsasser and Perrin 1935; Bethe 1935) these resonance phenomena in terms of the usual approximations of quantum collision theory were soon found to be inadequate, All such attempts were based on the assumption that the Chance of a nuclear collision being elastic is high compared with that of its resulting in capture or excitation. A high probability of capture (with emission of radiation) or excitation could then only appear together with a high probability of elastic collision and this is frequently contradicted by the experimental results. The sharpness of the observed resonance phenomena was also difficult to under­stand on this basis. It was first pointed out by Bohr (1936) that the initial assumptions concerning the probability of elastic collisions, virtually involving the treatment of the elastic scattering as a one-body problem in the first approximation, cannot be valid for nuclei in which the particles, even is existing separately in the nuclei at all, are so closely packed. On making a close collision with a nucleus a particle, such as an α -particle, neutron or proton, comes into close and strong interaction with a number of nuclear particles and its incident energy becomes distributed among them. It is only when a particular particle receives sufficient energy to leave the quasi-stable complex formed that a disintegration particle is emitted. (This may of course be the original incident particle, in which case the collision would be an elastic or excitation one.) Otherwise the surplus energy is emitted as radiation. The resonance phenomena arise from the energy levels of the quasi-stable complex. If the incident energy is such that the total energy is equal or nearly equal to that of one of these energy levels, the range of interaction and hence the collision cross-section is quite large. This point of view must be adopted not only when dealing with neutron collisions but in all cases in which the impinging particle does not possess an energy greatly in excess of the minimum necessary for the process to occur. Disintegrations produced by charged particles, in which resonance effects have been observed for some time (Feather 1937, P. 154), must therefore be capable of description in this way.


1996 ◽  
Vol 03 (01) ◽  
pp. 489-492 ◽  
Author(s):  
JIJUN ZHAO ◽  
XIAOSHUANG CHEN ◽  
FENGQI LIU ◽  
GUANGHOU WANG

The Su–Schrieffer–Heeger (SSH) Hamiltonian has been extended to study the electron–phonon interaction and the electronic structures of the alkali-like metal clusters. The eigen-energy levels of s valence electrons are obtained from a Hückel-like Hamiltonian including the correction of the electron–phonon interaction in the hopping integral, which is proportional to the variable of bond length. The self-consistent equations for electrons and phonons are solved adiabatically through an iteration process. The energy-level structures of an octahedral Cu6 cluster are calculated with variable electron–phonon coupling constant λ to investigate the influence of electron–phonon interaction on the lattice distortion and electronic structures of metal clusters. The size-dependent ionization potential for small Cun clusters are calculated and compared with the experimental results.


1999 ◽  
Vol 14 (32) ◽  
pp. 5137-5157 ◽  
Author(s):  
ROMAN TOMASCHITZ

A new interaction mechanism of superluminal particles with matter is suggested. Tachyons are described by a real Proca field with negative mass square, coupled to a current of subluminal matter. The potential of a static point source in this field theory is a damped periodic function with 1/r-decay. We treat this potential as a perturbation of the Coulomb potential, and study its effects on cross-sections and energy levels. In the limit of large impact parameter, the periodicity of the potential has a pronounced effect on the classical cross-section, which gets singular at the accumulating extrema of the scattering angle. In this limit we define the cross-section wave mechanically, by semiclassical rainbow scattering. The impact of the tachyon potential on the energy levels of hydrogen and hydrogenic ions is calculated by means of Bohr–Sommerfeld quantization. Estimates for the tachyon mass (3 keV) and the coupling constant of the tachyon potential are derived on the basis of high-precision Lamb shift measurements.


Author(s):  
U.V.S Seshavatharam ◽  
S. Lakshminarayana

As there exist no repulsive forces in strong interaction, in a hypothetical approach, strong interaction can be assumed to be equivalent to a large gravitational coupling. Based on this concept, strong coupling constant can be defined as a ratio of the electromagnetic force and the gravitational force associated with proton, neutron, up quark and down quark. With respect to the product of strong coupling constant and fine structure ratio, we review our recently proposed two semi empirical relations and coefficients 0.00189 and 0.00642 connected with nuclear stability and binding energy. We wish to emphasize that- by classifying nucleons as ‘free nucleons’ and ‘active nucleons’, nuclear binding energy can be fitted with a new class of ‘three term’ formula having one unique energy coefficient. Based on the geometry and quantum nature, currently believed harmonic oscillator and spin orbit magic numbers can be considered as the lower and upper “mass limits” of quark clusters.


2017 ◽  
Vol 57 (6) ◽  
pp. 385 ◽  
Author(s):  
Silvestro Fassari ◽  
Manuel Gadella ◽  
Luis Miguel Nieto ◽  
Fabio Rinaldi

<p>We propose a new approach to the problem of finding the eigenvalues (energy levels) in the discrete spectrum of the one-dimensional Hamiltonian with an attractive Gaussian potential by using the well-known Birman-Schwinger technique. However, in place of the Birman-Schwinger integral operator we consider an isospectral operator in momentum space, taking advantage of the unique feature of this potential, that is to say its invariance under Fourier transform. <br />Given that such integral operators are trace class, it is possible to determine the energy levels in the discrete spectrum of the Hamiltonian as functions of <span>the coupling constant with great accuracy by solving a finite number of transcendental equations. We also address the important issue of the coupling constant thresholds of the Hamiltonian, that is to say the critical values of λ for which we have the emergence of an additional bound state out of the absolutely continuous spectrum. </span></p>


Author(s):  
U. V. S. Seshavatharam ◽  
S. Lakshminarayana

To understand the mystery of final unification, in our earlier publications, we proposed that, 1) There exist three atomic gravitational constants associated with electroweak, strong and electromagnetic interactions; 2) There exists a strong interaction elementary charge in such a way that, it's squared ratio with normal elementary charge is close to inverse of the strong coupling constant; and 3) Considering a fermion-boson mass ratio of 2.27, quarks can be split into quark fermions and quark bosons. Further, we noticed that, electroweak field seems to be operated by a primordial massive fermion of rest energy 584.725 GeV and hadron masses seem to be generated by a new hadronic fermion of rest energy 103.4 GeV. In this context, starting from lepton rest masses to stellar masses, we have developed many interesting and workable relations. With further study, a workable model of final unification can be developed.


The thermal conductivity of crystals of concentrated cerium ethylsulphate has been measured in the range 1 to 4·58°K and in magnetic fields of up to 53 kG. In zero field there is a marked anomaly at 2·5°K in the variation of conductivity with temperature. Owing to the anisotropy of the g -values the magnetic field dependence of the thermal resistivity at constant temperature depends on the field direction; with the field parallel to the hexagonal axis, a maximum occurs in the resistivity which moves roughly linearly with temperature, and in very high fields it is always less than in zero field; with the field applied in the perpendicular direction a resistivity maximum is only observed above 2°K, and in the highest available field it is always much greater than in zero field. These results are explained by assuming that direct process phonon-spin interactions scatter certain bands of phonons whose frequency depends on the separation of the energy levels produced by the applied magnetic field. A statistical theory is used to determine the relative populations of the energy levels in the calculation of the thermal resistivity. It is assumed that the spin-phonon absorption lineshape is Gaussian. By fitting the theory to the experimental data, approximate values of the spin-lattice coupling constant, the linewidth of the transitions and the mean free paths for boundary and point-defect scattering are obtained.


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