ANOMALOUS HE ACCELERATION, THE PARTICLE SOURCE AND THE TRANSPORT COEFFICIENT

Anomalous He+ component acceleration at the heliospheric termination s hock is modelled numerically via a steady-state solution to the combin ed cosmic-ray transport equation and shock boundary condition via a ma trix inversion technique. This numerical solution automatically provid es a no-drift modulation solution for the He+. Consistency with experi mental data on the anomalous component is obtained for injection at 10 keV nucl(-1), at 120 AU, with a distribution function(-1) at 20 AU an d f(v) = 2.75 x 10(-24) m(-6) s(3) and a radial diffusion coefficient k = 2.24 x 10(22) cm(2) s(-1) for 100 MeV nucl(-1) particles but which varied proportional to v(gamma) r(delta) where v and r are, respectiv ely, particle velocity and solar distance, gamma = 1.3 and delta = 0.5 . However, a range of values of (gamma, delta) between (1,0) and (2.4, 1.4) were found to yield acceptable fits to the data. Pre-acceleration of ionised He at CIRs is possible as a source, although there is suff icient quiet-solar-wind-associated He+ for the required injection flux and the constraints on the injection efficiency are less at the termi nal shuck. These conclusions are insensitive to the terminal shock pos ition and to the value of the injection energy.