HAL : in2p3-00269906, version 1
 arXiv : 0804.0310
 The $^{8}$He and $^{10}$He spectra studied in the $(t$,$p)$ reaction
 (2008)
 The low-lying spectra of $^8$He and $^{10}$He nuclei were studied in the $^3$H($^6$He,$p$)$^8$He and $^3$H($^8$He,$p$)$^{10}$He transfer reactions. The $0^+$ ground state (g.s.) of $^8$He and excited states, $2^+$ at $3.6-3.9$ MeV and $(1^+)$ at $5.3-5.5$ MeV, were populated with cross sections of 200, 100-250, and 90-125 $\mu$b/sr, respectively. Some evidence for $^8$He state at about 7.5 MeV is obtained. We discuss a possible nature of the near-threshold anomaly above 2.14 MeV in $^8$He and relate it to the population of a $1^-$ continuum (soft dipole excitation) with peak value at about 3 MeV. The lowest energy group of events in the $^{10}$He spectrum was observed at $\sim 3$ MeV with a cross section of $\sim 140$ $\mu$b/sr. We argue that this result is possibly consistent with the previously reported observation of $^{10}$He, in that case providing a new g.s. position for $^{10}$He at about 3 MeV.
 Thème(s) : Physique/Physique Nucléaire Expérimentale
 Lien vers le texte intégral : http://fr.arXiv.org/abs/0804.0310
 in2p3-00269906, version 1 http://hal.in2p3.fr/in2p3-00269906 oai:hal.in2p3.fr:in2p3-00269906 Contributeur : Michel Lion <> Soumis le : Jeudi 3 Avril 2008, 11:16:02 Dernière modification le : Jeudi 3 Avril 2008, 14:17:13