The low-lying spectra of 8He and 10He nuclei were studied in the 3H(6He,p)8He and 3H(8He,p)10He transfer reactions. The 0+ ground state (g.s.) of 8He 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 μb/sr, respectively. Some evidence for 8He state at about 7.5 MeV is obtained. We discuss a possible nature of the near-threshold anomaly above 2.14 MeV in 8He 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 10He spectrum was observed at ∼3 MeV with a cross section of ∼140μb/sr. We argue that this result is possibly consistent with the previously reported observation of 10He, in that case providing a new g.s. position for 10He at about 3 MeV.
@article{arxiv.0804.0310,
title = {The $^{8}$He and $^{10}$He spectra studied in the $(t$,$p)$ reaction},
author = {M. S. Golovkov and L. V. Grigorenko and G. M. Ter-Akopian and A. S. Fomichev and Yu. Ts. Oganessian and V. A. Gorshkov and S. A. Krupko and A. M. Rodin and S. I. Sidorchuk and R. S. Slepnev and S. V. Stepantsov and R. Wolski and D. Y. Pang and V. Chudoba and A. A. Korsheninnikov and E. A. Kuzmin and E. Yu. Nikolskii and B. G. Novatskii and D. N. Stepanov and P. Roussel-Chomaz and W. Mittig and A. Ninane and F. Hanappe and L. Stuttge and A. A. Yukhimchuk and V. V. Perevozchikov and Yu. I. Vinogradov and S. K. Grishechkin and S. V. Zlatoustovskiy},
journal= {arXiv preprint arXiv:0804.0310},
year = {2009}
}