A systematic investigation has been made of ion-acoustic solitary waves in plasma consisting of cold positively and negatively charged ions, as well as nonthermal electrons. The basic features of the solitary waves are investigated by using the reductive perturbation method, which is valid for the small but finite amplitude waves. Computational investigations have been performed to examine the ...

We study both dissipative and nondissipative quantum transport in discrete Brownian rectifiers being driven by nonthermal noise that is unbiased on average. In the absence of dissipation the current is always zero and the ballistic diffusion changes into normal diffusion. The dissipative quantum dynamics exhibits current (with distinctive reversals) as a result of the cooperative interplay betw...

The pion production by sigma decay and its relation with chiral symmetry restoration in a hot and dense matter are investigated in the framework of the Nambu-Jona-Lasinio model. The decay rate for the process σ → 2π to the lowest order in a 1/Nc expansion is calculated as a function of temperature T and chemical potential μ. The thermal and nonthermal enhancements of pions generated by the deca...

I present a review of nonthermal processes in the large scale structure of the universe. After examining the properties of cosmological shock waves and their role as particle accelerators, I discuss the main observational facts, from radio to γ-ray and describe the processes that are thought be responsible for the observed nonthermal emissions. Finally, I emphasize the important role of γ-ray a...

It is shown that, for Broad Line Radio Galaxies the strength of the nonthermal beamed radiation, when present, is always smaller than the accretion flow by a factor < 0.7 in the 2-10 keV band. The result has been obtained using the procedure adopted for disentangling the Flat Spectrum Radio Quasar 3C 273 (Grandi & Palumbo 2004) Although this implies a significantly smaller nonthermal flux in Ra...

The inner couple hundred pcs of our Galaxy is characterized by significant amount of synchrotron-emitting gas, which appears to co-exist with a large reservoir of molecular gas. Many of the best studied sources in this region exhibit a mixture of 6.4 keV Fe Kα emission, molecular line emission and nonthermal radio continuum radiation. The spatial correlation between fluorescent Fe K-α line emis...