Search for superheavy hydrogen isotopes 6H and 7H in stopped π-absorption reactions

Search forH7inH2+Nikolskii1, Korsheninnikov2, Otsu3 et al. 2010Phys. Rev. C230150View full textAdd to dashboardCite

“…A primary 18 O beam with energy 100 A MeV and intensity of ∼500 particle nA bombarded a 9 Be target with a thickness of 12 mm. The secondary beam consisted of a cocktail of 8 He and 12 Be with average energies of 42 and 71 A MeV, and intensities of 1.4 × 10 5 and 2.6 × 10 5 pps, respectively. A cryogenic target cell was used, supplied with 6.5-µm Havar windows, and filled with deuterium gas at 30 K and a pressure of 0.5 atm.…”

“…The beam energy and parameters of the detection system were optimized by utilizing the results obtained in complete Monte-Carlo simulations preceding the experiment. The presence of 12 Be nuclei in the beam enabled us to study the 2 H( 12 Be, 3 He) 11 Li reaction, as discussed later in this article.…”

“…Stopped π − -meson absorption in 9 Be and 11 B targets was recently studied in Ref. [12] where some peculiarity in the spectrum near the threshold was found in the 11 B(π − , p 3 He) 7 H reaction, but no evidence for the low-lying 7 H state was observed in the 9 Be(π − , pp) 7 H channel. Very recently, the question of the 7 H existence was investigated via the use of the transfer reaction 12 C( 8 He, 13 N) 7 H [13].…”

The $^{6}$H states studied in the $^2\text{He}(^8\text{He},^4\text{He})$ reaction and evidence of extremely correlated character of the $^{5}$H ground state

“…Recently, reliable spectroscopic information was obtained on the extreme neutron-rich system 7 H produced in the 2 He( 8 He, 3 He) 7 H reaction [ 1,2,3]. The 6 H population in the 2 He( 8 He, 4 He) 6 H reaction, making the subject of the present work, is a natural "satellite" channel for the aforementioned experiment.…”

“…The authors of Ref. [ 4] reported a value E T = 2.7(4) MeV (energy above the 3 H+3n decay threshold) for the 6 H state produced in the 7 Li( 7 Li, 8 B) 6 H reaction. A bit later this result was somehow confirmed in Ref.…”