The production of radioisotopes for use in biomedical procedures such as diagnostic imaging and/or therapeutic treatments is achieved through nuclear reactions in reactors or from charged particle bombardment in accelerators. In reactors the nuclear reactions are initiated with neutrons while in accelerators the typical charged particle reactions utilize protons although deuterons and α−particl...

We point out that in certain four-dimensional extensions of general relativity constructed within the Palatini formalism stable self-gravitating objects with a discrete mass and charge spectrum may exist. The incorporation of nonlinearities in the electromagnetic field may effectively reduce their mass spectrum by many orders of magnitude. As a consequence, these objects could be within (or nea...

The optimization of the performance of any particle accelerator critically depends on an in-depth understanding of the beam dynamics, powerful simulation tools and beam diagnostics, as well as a control and data acquisition system that links all the above. The oPAC consortium has carried out collaborative research into these areas, with the aim to optimize the performance of present and future ...

We present the theoretical arguments and describe the accumulating experimental evidence that jets, powered by supermassive black holes, are true cosmic accelerators. They produce photons of TeV energy, possible higher, and may be the enigmatic source of the highest energy cosmic rays. The features of the multiwavelength emission spectrum are dictated by the interactions of electrons and proton...