High energy-density plasma dynamics in plasma-filled rod-pinch diodes

High energy-density plasma (HEDP) is created using a plasma-filled rod pinch diode (PFRP) [1] on the Gamble II generator. HEDP is produced by a 1-2 MeV, 500 kA electron beam that deposits energy at the end of a tungsten rod. When the rod is tapered to a point, the energy density is estimated to reach 2.4 MJ/cm³ in about 10 ns, before rapid expansion decreases the energy density. Recent measurements show that the temperature peaks at about 30 eV at the time of maximum energy density, and that the time-averaged ionization is about +17, similar to MHD model predictions [2]. The plasma mass distribution is inferred from X-ray distribution measurements. The time-dependent mass distribution is used to calculate the mass density and plasma pressure. These measurements indicate the HEDP is strongly coupled (Γ = 35) with peak pressure (16 Mb) about 7 times greater than n_ekT.High energy-density plasma (HEDP) is created using a plasma-filled rod pinch diode (PFRP) [1] on the Gamble II generator. HEDP is produced by a 1-2 MeV, 500 kA electron beam that deposits energy at the end of a tungsten rod. When the rod is tapered to a point, the energy density is estimated to reach 2.4 MJ/cm³ in about 10 ns, before rapid expansion decreases the energy density. Recent measurements show that the temperature peaks at about 30 eV at the time of maximum energy density, and that the time-averaged ionization is about +17, similar to MHD model predictions [2]. The plasma mass distribution is inferred from x-ray distribution measurements. The time-dependent mass distribution is used to calculate the mass density and plasma pressure. These measurements indicate the HEDP is strongly coupled (Γ = 35) with peak pressure (16 Mb) about 7 times greater than n_ekT.