We trace the evolution of research on extreme solar and solar-terrestrial events from the
1859 Carrington event to the rapid development of the last twenty years. Our focus is on the …

Solar energetic particles, or SEPs, from suprathermal (few keV) up to relativistic (∼∼ few
GeV) energies are accelerated near the Sun in at least two ways:(1) by magnetic …

Abstract One century ago Viktor Hess carried out several balloon flights that led him to
conclude that the penetrating radiation responsible for the discharge of electroscopes was of …

Among the various acceleration mechanisms which have been suggested as responsible for
the nonthermal particle spectra and associated radiation observed in many astrophysical …

HIGH-ENERGY cosmic rays (relativistic heavy nuclei) play an important role in heating
interstellar matter in the Milky Way1, 2, and they affect chemical abundances through …

The notion that plasma shocks in astrophysical settings can and do accelerate charged
particles to high energies is not a new one. However, in recent years considerable progress …

We consider the acceleration of charged particles near ultrarelativistic shocks, with Lorentz
factor. We present simulations of the acceleration process and compare these with results …

Cosmic-ray particles with energies in excess of 1020eV have been detected. The sources as
well as the physical mechanism (s) responsible for endowing cosmic-ray particles with such …

The hard state of X-ray binaries (XRBs) is characterized by a power-law spectrum in the X-
ray band and a flat/inverted radio/IR spectrum associated with occasionally imaged compact …

The spectral energy distribution (SED) of gamma-ray (γ-ray) loud BL Lac objects typically
has a double-humped appearance usually interpreted in terms of synchrotron self-Compton …