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Hyperon dynamics and production of multi-strangeness hypernuclei in heavy-ion collisions at 3A GeV

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 نشر من قبل Zhaoqing Feng
 تاريخ النشر 2021
  مجال البحث
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Within the microscopic transport, systematic investigation of the many facets of hyperons and hypernuclei up to strangeness $S = -2$ are carried out for $^{197}$Au + $^{197}$Au and $^{40}$Ca + $^{40}$Ca at the incident energy of $3A$ GeV. The spatial, temporal and density distributions of hyperon production, absorption and freeze-out are thoroughly investigated. The rapidity and kinetic energy spectra of $Xi$ hyperons and double $Lambda$ hypernuclei are analyzed. It is revealed that the chemical balance of hyperon production is established in baryon-baryon channels while the opposite is found in baryon-meson channels. It turns out that the rapidity spectra of $^{4,5}_{LambdaLambda}$X are single-peak and more than two orders of magnitude lower than that of $^{3}_{Lambda}$H. Formation of double $Lambda$ hypernuclei through $Xi$ hypernuclei as intermediate states is also discussed in kinematics.

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