Nova is accelerating at the theoretical limit

The RS-Ophiuchi white dwarf turns out to be one of the most efficient particle accelerators in the universe. A team led by Alison Mitchell of the University of Erlangen-Nuremberg also determined that a new remnant supernova is accelerating protons and heavier atomic nuclei to their highest theoretically possible energies. The high-energy radiations emitted by novas, combined with computer models, show that the particles accelerated by the explosion have energies hundreds of times higher than in previous novas, The team reports in “Science”.. The finding highlights why some novae emit gamma rays and suggests that such frequent supernovae are an important source of high-energy cosmic rays.