Publications by authors named "A Gumberidze"

Stable ^{205}Tl ions have the lowest known energy threshold for capturing electron neutrinos (ν_{e}) of E_{ν_{e}}≥50.6  keV. The Lorandite Experiment (LOREX), proposed in the 1980s, aims at obtaining the longtime averaged solar neutrino flux by utilizing natural deposits of Tl-bearing lorandite ores.

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Article Synopsis
  • Radioactive nuclei that live for millions of years help us understand the Sun's formation and the nucleosynthesis happening when it was born, with lead (Pb) being a key example.
  • Recent measurements of the weak decay of ionized thallium (Tl) provided a more accurate half-life, which was found to be 4.7 times longer than previously thought, thus reducing uncertainty in our calculations.
  • Using these improved decay rates, researchers calculated lead yields in asymptotic giant branch (AGB) stars, confirmed isolation times for solar material, and validated the theory that the Sun formed in a long-lived molecular cloud.
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The nuclear two-photon or double-gamma (2γ) decay is a second-order electromagnetic process whereby a nucleus in an excited state emits two gamma rays simultaneously. To be able to directly measure the 2γ decay rate in the low-energy regime below the electron-positron pair-creation threshold, we combined the isochronous mode of a storage ring with Schottky resonant cavities. The newly developed technique can be applied to isomers with excitation energies down to ∼100  keV and half-lives as short as ∼10  ms.

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Article Synopsis
  • * Experiments on highly charged ions, particularly uranium, are complicated but critical for studying the effects of strong electromagnetic fields on QED calculations, which behave differently under these conditions.
  • * The research presented achieved precise measurements of electron interactions in uranium ions, allowing for tests of both individual electron effects and interactions between multiple electrons, contributing valuable data for theoretical models in strong-field QED.
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