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Transition from Thermal to Rapid Expansion in Multifragmentation of Gold Induced by Light Relativistic Projectiles

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 نشر من قبل Helmut Oeschler
 تاريخ النشر 2001
  مجال البحث
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Multiple emission of intermediate-mass fragments has been studied for the collisions of p, $^4$He and $^{12}$C on Au with the $4pi$ setup FASA. In the case of $^{12}$C(22.4 GeV)+Au and $^4$He(14.6 GeV)+Au collisions, the deviations from a pure thermal break-up are seen in the energy spectra of the emitted fragments: the spectra are harder than calculated and than measured in p-induced collisions. This difference is attributed to a collective flow with the expansion velocity on the surface about 0.1 $c$ (for $^{12}$C+Au collisions).



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