H4and (n,αx) reactions on

Abstract

The cross sections for the 6Li(n, ax) and 7Li(n, ox) reactions have been measured by the detection of a particles in coincidence with other charged particles (x). Prominent structures in the coincident a-particle energy spectra have been observed only in the case of 7Li. They could be attributed to the processes involving the states of H.The four-nucleon system is the lightest few-nucleon system to exhibit resonances at low energies. The only partide stable state is the ground state of 4He. There is now enough evidence showing that 4H and 4Li have only broad particle unstable states. Ho~ever, the data on the positions and widths of these states have often been contradictory, especially in the case of 4H.

Ground-state properties of super-heavy hydrogen-7

“…One-proton transfer reactions correlate the angle and range of the target-like recoils following kinematic lines that depend on the mass of the nuclei involved, including the 7 H. Figure 2 shows this correlation for the measured data, along kinematic lines corresponding to two reference values for the 7 H mass. The accumulation of events around the kinematic lines of Q F and Q C in Fig.…”

“…In a proton-transfer event producing 7 H, the trajectory of the 8 He projectile is measured by the CATS beam-tracking detectors before entering MAYA. Once inside, the 8 He projectile interacts with either a 12 C or 19 F nucleus and transfers a proton, yielding a 13 N or 20 Ne target-like recoil and a 7 H resonance that, less than 10 −20 s after the reaction, decays into a 3 H nucleus and four neutrons.…”

“…The selection of 7 H candidate events is done with the simultaneous measurement of the reaction charged products. A measured proton-transfer reaction with 12 C or 19 F consists of a single 3 H detected in the dE-E telescope in coincidence with a single trajectory from the target-recoil product, projected on the pad plane.…”

“…7 H is expected to display unusual characteristics and open questions. Neutron pairing may render 7 H the least unstable of the chain despite being the most neutron-rich, forcing it to decay directly to 3 emitting four neutrons simultaneously [24,29]. However, other theoretical models predict the resonance to be ∼3 MeV above the 3 H+4n mass [30,31], and thus favouring a sequential neutron emission over a unique simultaneous decay.…”

H4nucleus and theHBlagus1, Miljanić2, Задро3 et al. 1991Phys. Rev. CSelf Cite19090View full textAdd to dashboardCite

“…The cross section for the sequential decay was calculated using a resonance form [5,7] It is hoped that a complete analysis of all data from the [10] [10] [3]…”