Baryonium and the four-body problem

Barbour, I.M.; Ponting, D. K.

doi:10.1016/0550-3213(79)90007-5

Cited by 30 publications

(7 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Calculations have been carried out in the area of subnuclear physics [4], nuclear physics [5,6], atomic physics [7], condensed-matter physics [8], and quantum chemistry [9,10]. Two of the more startling results were the discovery that many neutral atoms could form electronic stable states with a positron [11,12] and the recent calculations on small molecules going beyond the Born-Oppenheimer approximation [10].…”

Section: Introductionmentioning

confidence: 99%

Stochastic variational calculation of zero-energy positron scattering from H, He, andH2

Zhang

Mitroy

2011

Phys. Rev. A

View full text Add to dashboard Cite

The confined variational method is used to generate a set of energy-optimized explicitly correlated Gaussians to describe positrons interacting with H, He and the H 2 molecule. These basis functions are then used in a Kohn variational calculation of the scattering lengths and zero-energy annihilation parameters, Z eff . The results for the H and He atoms are consistent with previous high-quality variational calculations while the annihilation parameter for H 2 is consistent with experiment. An extensive tabulation of the H 2 scattering parameters as a function of internuclear distance confirm the existence of a virtual state at R ≈ 3.4a 0 . The scattering length was −2.71a 0 and Z eff was 15.7 at the mean H 2 internuclear distance of 1.45a 0 .

show abstract

Section: Introductionmentioning

confidence: 99%

Stochastic variational calculation of zero-energy positron scattering from H, He, andH2

Zhang

Mitroy

2011

Phys. Rev. A

View full text Add to dashboard Cite

show abstract

“…In recent years, the SVM and related methods have been used by many groups to perform high precision variational calculations in atomic, mesoatomic, hypernuclear and multiquark systems [7,[14][15][16]. Recently, the SVM has been modified to allow the calculation of excited states and also to permit the use of a wide variety of non-central forces [17,18].…”

mentioning

confidence: 99%

Positronic Lithium, an Electronically StableLi−e+Ground State

1997

View full text Add to dashboard Cite

Calculations of the positron-Li system were performed using the stochastic variational method, yielding a minimum energy of 27.532 08 hartree for the L 0 ground state. In contrast with previous calculations of this system, the system was found to be stable against dissociation into the Ps 1 Li 1 channel with a binding energy of 0.002 17 hartree; it is therefore electronically stable. This is the first instance of a rigorous calculation predicting that it is possible to combine a positron with a neutral atom to form an electronically stable bound state. [S0031-9007(97)04578-X] PACS numbers: 36.10. Dr, 31.15.Ar One of the most tantalizing questions of positron physics is: Is it possible for a positron to bind itself to a neutral atom and form an electronically stable state [1,2]? This question can be answered only by a sophisticated calculation (or experimentation) as the mechanisms responsible for binding the positron to the atom are polarization potentials present in the positron-atom complex. The accurate computation of the polarization potential for a positron-atom (or electron-atom) system is of course a challenging exercise in many-body physics.While the question of whether it is possible to bind a positron to a neutral atom is an open question, the ability of positronium to attach itself to atoms has been known for a long time. A number of previous works have demonstrated that the positronium-hydride (PsH) species [3][4][5][6][7][8] is stable against dissociation into the Ps 1 H or the e 1 1 H 2 channels. In this case, binding is more likely since the positron is binding itself to a species with an overall negative charge.The question of whether a positron can form an electronically stable bound state with a neutral atom is more vexing. Dzuba et al. [9] have made calculations suggesting that it is possible to bind a positron to atomic species with two valence electrons such as Mg, Zn, Cd, and Hg. These calculations were performed in the framework of the many-body perturbation theory, and their results, while suggestive, cannot be regarded as providing proof to the existence of electronically stable positronic atoms.In their work, Dzuba et al. [9] did not consider the possibility of positrons forming bound states with alkali atoms such as Li, Na, K, . . . even though the polarization potential for these species should be stronger than for the alkaline and alkaline earth atoms and therefore the possibility of binding should be improved. One difficulty in binding positrons to alkali atoms is that the ionization energy of the alkali atoms is smaller than the binding energy of positronium. Therefore the binding energy of the positron to the neutral atom must exceed a particular value for the species to be stable against dissociation into positronium 1 ion. For example, for the Li-e 1 species to be stable against dissociation into positronium plus Li 1 requires that the binding energy of the e 1 with respect to the Li ground state be greater than ͑0.25 0.198 15͒ hartree. In this respect, it is more appropriate...

show abstract

“…Four-quark models were initially considered only with light flavors, but soon models with heavy quarks emerged [4,5]. These exotic states may have two constitutional structures, tetraquark and meson 'molecule' [6,7]. The tetraquark includes a di-quark and a di-antiquark, while, the meson 'molecule' is made of two meson clusters and it was expected that these structures give the same results in the same flavor, color, and spin representation [7].…”

Section: Introductionmentioning

confidence: 99%

Exotic states with QQQ′¯Q′¯ configuration

Aghbolaghi

Boroun

2023

Commun. Theor. Phys.

View full text Add to dashboard Cite

In the framework of a non-relativistic quark model, we have calculated the masses of the \textcolor{red}{$QQ\bar{Q'}\bar{Q'}$} ($Q = c,b,s$ and $ \textcolor{red}{\bar Q'= \bar c, \bar b,\bar s}$) tetraquark states. Using the linear and quadratic confinement potentials inside a Cornell-type potential along with all possible spin and color configurations, the Schroedinger equation masses of these tetraquark states have been calculated. Based on our numerical analysis, linear confinement and quadratic confinement produce acceptable results. Models that use linear confinement estimated charmonium-like tetraquark mass close to experimental data, as well as bottomonium-like tetraquark mass below the threshold of their meson-meson channels.

show abstract

Baryonium and the four-body problem

Cited by 30 publications

References 12 publications

Stochastic variational calculation of zero-energy positron scattering from H, He, andH2

Stochastic variational calculation of zero-energy positron scattering from H, He, andH2

Positronic Lithium, an Electronically StableLi−e+Ground State

Exotic states with QQQ′¯Q′¯ configuration

Contact Info

Product

Resources

About