Creation of a homogeneous plasma column by means of hohlraum radiation for ion-stopping measurements

In this work, we present the results of two-dimensional radiation-hydrodynamics simulations of a hohlraum target whose outgoing radiation is used to produce a homogeneously ionized carbon plasma for ion-beam stopping measurements. The cylindrical hohlraum with gold walls is heated by a frequency-doubled (λl = 526.5 μm) 1.4 ns long laser pulse with the total energy of El = 180  J. At the laser spot, the peak matter and radiation temperatures of, respectively, T ≈ 380 eV and Tr ≈ 120 eV are observed. X-rays from the hohlraum heat the attached carbon foam with a mean density of ρC = 2 mg/cm3 to a temperature of T ≈ 25 eV. The simulation shows that the carbon ionization degree (Z ≈ 3.75) and its column density stay relatively stable (within variations of about ±7%) long enough to conduct the ion-stopping measurements. Also, it is found that a special attention should be paid to the shock wave, emerging from the X-ray heated copper support plate, which at later times may significantly distort the carbon column density traversed by the fast ions.