Carlo Cereceda

Stopping power for arbitrary angle between test particle velocity and magnetic field

Using the longitudinal dielectric function derived previously for charged test particles in helical movement around magnetic field lines, the numerical convergence of the series involved is found and the double numerical integrations on wave vector components are performed yielding the stopping power for arbitrary angle between the test particle velocity and magnetic field. Calculations are performed for particle Larmor radius larger and shorter than Debye length, i.e., for protons in a cold magnetized plasma and for thermonuclear α particles in a dense, hot, and strongly magnetized plasma. A strong decrease is found for the energy loss as the angle varies from 0 to π∕2. The range of thermonuclear α particles as a function of the velocity angle with respect to the magnetic field is also given.

Kinetic theory of alpha particles production in a dense and strongly magnetized plasma

In connection with fundamental issues relevant to magnetized target fusion, the distribution function of thermonuclear alpha particles produced in situ in a dense, hot, and strongly magnetized hydrogenic plasma considered fully ionized in a cylindrical geometry is investigated. The latter is assumed in local thermodynamic equilibrium with Maxwellian charged particles. The approach is based on the Fokker–Planck equation with isotropic source S and loss s terms, which may be taken arbitrarily under the proviso that they remain compatible with a steady state. A novel and general expression is then proposed for the isotropic and stationary distribution f(v). Its time-dependent extension is worked out numerically. The solutions are valid for any particle velocity v and plasma temperature T. Higher order magnetic and collisional corrections are also obtained for electron gyroradius larger than Debye length. f(v) moments provide particle diffusion coefficient and heat thermal conductivity. Their scaling on colli...

Heavy ion–plasma interaction of IFE concern: Where do we stand now?

Two distinct issues of recent concern for ion-plasma interactions are investigated. First, the subtle connection between quantum and classical ion stopping is clarified by varying the space dimension. Then we evaluate the range of thermonuclear αs in dense plasmas simultaneously magnetized and compressed.

Magnetized Inhomogeneous Dusty Plasma Unstable Modes

The propagation of waves in unmagnetized dusty plasmas has been extensively studied in last years, describing DAW and DIAW modes. For magnetized, inhomogeneous dusty plasmas exists a series of works describing the theory of wave propagation, mainly fluid like description. However, there is a lack of detailed calculation and description of modes, being limited the recent works to magnetized electrons and neglecting the magnetization of ions and dust particles. In this work, we perform a detailed description of the whole magnetized system from full kinetic treatment and show detailed calculation of the unstable modes associated to ion and dust grains. High precision four pole approximations for the Z dispersion function are used. Comparison with previous results in the limiting cases are provided.

Distribution Function of Charged Particles in a Plasma of Fusion Interest

The non-Maxwellian distribution function of charged particles injected into a deuterium– tritium plasma has been found by Cozzani and Horton, and by Liberman and Velikovich,. They use an approximation of the collision integral in the Landau form which is valid for charged particle velocities much smaller than the plasma electron thermal velocity and much larger than plasma ion thermal velocity. If the charged particles are alpha particles generated by deuterium–tritium fusion of a plasma at temperatures in the range from 5 to 30 keV, the previous assumptions are no longer valid. In this work, the Fokker–Planck coefficients are used following the idea suggested by Gus’kov et al., but without neglecting the diffusion coefficient. A second order differential equation for the distribution function is obtained instead of a first order one of previous works. By this way, a general solution of this equation has been found which is valid for all the range of temperatures of fusion interest.