Kelvin-Helmholtz driven propeller in AE Aquarii: A unified model for thermal and non-thermal flares

Fireball Models for Flares in AE Aquarii

We examine the flaring behaviour of the cataclysmic variable AE Aqr in the context of the ‘magnetic propeller’ model for this system. The flares are thought to arise from collisions between high density regions in the material expelled from the system after interaction with the rapidly rotating magnetosphere of the white dwarf. We calculate the first quantitative models for the flaring and calc...

Thermal and non-thermal energies of solar flares

The energy of the thermal flare plasma and the kinetic energy of the non-thermal electrons in 14 hard X-ray peaks from 9 medium-sized solar flares have been determined from RHESSI observations. The emissions have been carefully separated in the spectrum. The turnover or cutoff in the low-energy distribution of electrons has been studied by simulation and fitting, yielding a reliable lower limit...

Distinguishing Between Thermal and Non-Thermal Electrons in Solar Flares Using X-Ray Observations

1. Science Summary A large variety of astrophysical objects are sites of powerful particle acceleration and impulsive energy release. The Sun provides us with an excellent nearby opportunity to study the physical mechanisms that drive these processes. Rapid changes in the highly-stressed magnetic fields of solar flares lead to large-scale energy release of up to ~10 ergs per second. These explo...

Interplay between Kelvin-Helmholtz and urrent-driven instabilities in jets

A search for TeV emission from AE Aquarii

We have observed the cataclysmic variable AE Aqr for a total of 68.7 hours over the epoch 1991-95 using the Whipple Observatory 10 m gamma-ray telescope. An analysis of these data has revealed no evidence for any steady, pulsed or episodic TeV emission. We have calculated an upper limit for steady emission of 4.0 x lo-‘* photons cm-‘s-l at an energy threshold of 900 GeV. This is three orders of...