Measurements of d+d(yields)(sup 3)He+n cross section at ultralow energies using Z-pinch

摘要

Direct experimental estimates of the upper limit of the d+d(yields)(sup 3)He+n cross section at deuteron energies below the keV region is obtained for the first time. The experiment was performed at the Pulsed Ion Beam Accelerator of the High-Current Electronics Institute in Tomsk, using high intensity, radially converging deuteron beams, generated during implosion of linear plasma. The parameters of the accelerator are: maximum current - 750 kF; voltage - 700 kV; rise time of current up to maximum value - 60 ns. A two-jet liner made of 17%D(sub 2) + 83%N(sub 2) gas, was used, with the inner jet serving as a target. The dd-fusion neutrons were registered by time-of-flight scintillator spectrometers and BF(sub 3) detectors of thermal neutrons placed in polyethylene moderator. The upper limit obtained for the d+d(yields)(sup 3)He+n cross-section for a deuteron energy of 400 eV is (sigma)<10(sup -33) cm(sup 2) at a 90% confidence level. The result demonstrates that liner implosion technique can be used in the investigations of nuclear reactions between light nuclei at infra low energies, previously not accessible in experiments with classical beam accelerators. 14 refs., 3 figs., 2 tabs. (Atomindex citation 27:060951)