Study of D-D Reaction at the Plasma Focus Device

Abstract

Abstract. The plasma focus device PF-1000 at IPPLM Warsaw with neutron yields of 10 9 -10 11 neutrons per shot is convenient for the determination of the axial neutron energy distribution in the fusion D-D reaction due to the horizontal position of a discharge axis and the distance of scintillation detectors up to 85 m from the neutron source in both axial (downstream and upstream) directions. In this paper the determination of the axial energy component of the fast deuterons producing neutrons is presented for the shot with a relative small neutron yield and nearly isotropic neutron energy distribution and the total energy of fast deuterons producing neutrons is estimated. We calculated, if the dense structure with the length of 2 cm and the density of 2x10 25 m -3 could be the source of neutrons. We estimated the upper limit of energy of deuterons producing neutrons as 10-20 keV and their total number as 10 18 . The deuterons with energies below 10-20 keV can't produce high number of neutrons due to the small cross-section of D-D reaction but they can be principally confined by magnetic field. We discuss the influence of magnetic field on the motion of deuterons.

Research on soft x-rays in high-current plasma-focus discharges and estimation of plasma electron temperature

“…It has been proved that the development of a PF discharge depends substantially on parameters of the coaxial electrodes and solid insulator as well as on the initial gas pressure [8][9][10][11][12]. The emission of intense x-ray pulses and fusion-produced neutrons (from PF discharges performed with the deuterium filling) have been investigated in details, and many efforts have concerned the optimisation of the x-ray and neutron yields [12][13][14]. Many measurements have shown that the neutron yield maximum appears at a slightly higher gas pressure than the x-ray yield peak [1,10,11].…”

“…Many theoretical and experimental efforts were devoted to the determination of scaling laws for the fusion-neutron production and to measurements of the basic plasma parameters, i.e. electron density and temperature [6,[14][15][16][17]. To investigate the electron density distribution the use was made of optical emission spectroscopy (OES) and laser interferometry (LI) methods.…”

On the representation of dense plasma focus as a circuit element

“…Because of dynamo activities, current streamlines may condense into local quasi-closed formations like balls of wool with free ends, that can transport the current from the anode to the cathode even after plasma breakup. Such "balls of current streamlines" would be visible as plasma structures in VUV [18] and interferometry images [17] and be manifested as ball-like fast ion traps in reaction product images [20,21].…”