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Observation of the $^7$H excited state

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 نشر من قبل Vratislav Chudoba
 تاريخ النشر 2019
  مجال البحث
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The $^7$H system was populated in the $^2$H($^8$He,$^3$He)$^7$H reaction with a 26 AMeV $^8$He beam. The $^{7}$H missing mass energy spectrum, the $^{3}$H energy and angular distributions in the $^7$H decay frame were reconstructed. The $^7$H missing mass spectrum shows a peak which can be interpreted either as unresolved $5/2^+$ and $3/2^+$ doublet or one of these states at 6.5(5) MeV. The data also provide indications on the $1/2^+$ ground state of $^7$H located at 2.0(5) MeV with quite a low population cross section of $sim 10$ $mu$b/sr within angular range $theta_{text{cm}} simeq 6^{circ} - 30^{circ}$.



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