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 alpha 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 pi/2. The range of thermonuclear alpha particles as a function of the velocity angle with respect to the magnetic field is also given. (C)2005 American Institute of Physics.