Centrifugal mechanism of acceleration
Centrifugal acceleration of astroparticles to relativistic energies might take place in rotating astrophysical objects (see also Fermi acceleration). It is strongly believed that AGN and Pulsars have rotating magnetospheres, therefore, they potentially can drive charged particles to high and ultra high energies.
It is well known that the magnetospheres of AGN and Pulsars are characterized by strong magnetic fields, which in turn, might force the charged particles to follow the field lines. On the other hand, if the magnetic field lines are rotating (which is the case for the above-mentioned astrophysical objects) the particles will inevitably undergo centrifugal acceleration. In the pioneering work by Machabeli & Rogava was considered a gedanken experiment: a bead moving inside a straight rotating pipe. Dynamics of a particle was analyzed as analytically as numerically and it has been shown that if the rigid rotation is maintained for a sufficiently long time energy of the bead will asymptotically increase. In particular, Rieger & Mannheim, based on the theory developed by Machabeli & Rogava have shown that the Lorentz factor of the bead behaves as
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