Precise Values for Critical Fields in Quantum Electrodynamics

A careful investigation of different corrections to binding energies of electrons in almost critical fields is performed. We investigate quantitatively the influence of the nuclear charge parameters, nuclear mass, degree of ionization on the value of the critical charge of the nucleus. Rather qualitative arguments are given to establish the contribution of the quantumelectrodynamic corrections, which are found to be small. Some phenomenological modifications of QED are quantitatively investigated and found to be of negligible influence on the value of the critical field. For heavy ion collisions with Z1+Z2>Zcr the critical separations between ions are given as results of precise solutions of the relativistic two coulomb center problem. Corrections due to electron-electron interaction are considered. We find (with present theoretical accuracy) Zcr=173±2, in the heavy ion collisions Rcr(U-U) = 34.7±2 fm and Rcr (U-Cf)=47.7±2 fm. We shortly consider the possibility of spontaneous muon production in muonic supercritical fields.

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New calculations for heavy-ion collisions with super-critical fields

Journal of Physics Conference Series ◽

10.1088/1742-6596/88/1/012017 ◽

2007 ◽

Vol 88 ◽

pp. 012017 ◽

Cited By ~ 5

Author(s):

E Ackad ◽

M Horbatsch

Keyword(s):

Heavy Ion Collisions ◽

Heavy Ion ◽

Critical Fields ◽

Ion Collisions

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The influence of electron-electron interaction on inner-shell excitation processes in heavy-ion collisions

Journal of Physics B Atomic and Molecular Physics ◽

10.1088/0022-3700/17/4/017 ◽

1984 ◽

Vol 17 (4) ◽

pp. 615-640 ◽

Cited By ~ 32

Author(s):

T H J de Reus ◽

J Reinhardt ◽

B Muller ◽

W Greiner ◽

G Soff ◽

...

Keyword(s):

Heavy Ion Collisions ◽

Heavy Ion ◽

Electron Interaction ◽

Ion Collisions ◽

Excitation Processes

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Production of light nuclei in heavy ion collisions via hagedorn resonances

The European Physical Journal A ◽

10.1140/epja/s10050-020-00329-z ◽

2021 ◽

Vol 57 (2) ◽

Author(s):

K. Gallmeister ◽

C. Greiner

Keyword(s):

Experimental Data ◽

Heavy Ion Collisions ◽

Heavy Ion ◽

Decay Rates ◽

Binding Energies ◽

Light Nuclei ◽

Saha Equation ◽

Ion Collisions ◽

Chemical Freeze ◽

Freeze Out

AbstractThe physical processes behind the production of light nuclei in heavy ion collisions are unclear. The successful theoretical description of experimental yields by thermal models conflicts with the very small binding energies of the observed states, being fragile in such a hot and dense environment. Other available ideas are delayed production via coalescence, or a cooling of the system after the chemical freeze-out according to a Saha equation, or a ‘quench’ instead of a thermal freeze-out. A recently derived prescription of an (interacting) Hagedorn gas is applied to consolidate the above pictures. The tabulation of decay rates of Hagedorn states into light nuclei allows to calculate yields usually inaccessible due to very poor Monte Carlo statistics. Decay yields of stable hadrons and light nuclei are calculated. While the scale-free decays of Hagedorn states alone are not compatible with the experimental data, a thermalized hadron and Hagedorn state gas is able to describe the experimental data. Applying a cooling of the system according to a Saha-equation with conservation of nucleon and anti-nucleon numbers leads to (nearly) temperature independent yields, thus a production of the light nuclei at temperatures much lower than the chemical freeze-out temperature is compatible with experimental data and with the statistical hadronization model.

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Selected highlights of the production of light (anti-)(hyper-)nuclei in ultra-relativistic heavy-ion collisions

The European Physical Journal A ◽

10.1140/epja/s10050-020-00275-w ◽

2020 ◽

Vol 56 (11) ◽

Author(s):

Benjamin Dönigus

Keyword(s):

Heavy Ion Collisions ◽

Heavy Ion ◽

Binding Energies ◽

Relativistic Heavy Ion Collisions ◽

Current Status ◽

Separation Energy ◽

Proton Proton ◽

Thermal Models ◽

Ion Collisions ◽

Production Models

AbstractThe production of light (anti-)nuclei and (anti-)hypernuclei in ultra-relativistic heavy-ion collisions, but also in more elementary collisions as proton–proton and proton–nucleus collisions, became recently a focus of interest. In particular, the fact that these objects are all loosely bound compared to the temperature and energies, e.g. the kinetic energies involved, is often stressed out to be special for their production. The binding energies of these (anti-)nuclei is between 130 keV ($${\mathrm {\Lambda }}$$ Λ separation energy in the hypertriton) and about 8 MeV per nucleon. Whereas the connected temperatures are of the order of 100 to 160 MeV. This lead to some difficulties in the interpretation of the usually discussed production models, i.e. coalescence and statistical-thermal models, as will be discussed here. In this brief review we discuss selected highlights of the production of light (anti-)nuclei, such as (anti-)deuteron, (anti-)helium and (anti-)alpha nuclei. In addition, we will discuss the current status of the highly debated lifetime of the (anti-)hypertriton and connected measurements and model results.

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