Astronomy and Astrophysics – Astrophysics
Scientific paper
2003-01-17
Astronomy and Astrophysics
Astrophysics
14 pages, 4 figures, accepted for publication in Solar Physics
Scientific paper
An explicitly energy-conserving full orbit code CUEBIT, developed originally to describe energetic particle effects in laboratory fusion experiments, has been applied to the problem of proton acceleration in solar flares. The model fields are obtained from solutions of the linearised MHD equations for reconnecting modes at an X-type neutral point, with the additional ingredient of a longitudinal magnetic field component. To accelerate protons to the highest observed energies on flare timescales, it is necessary to invoke anomalous resistivity in the MHD solution. It is shown that the addition of a longitudinal field component greatly increases the efficiency of ion acceleration, essentially because it greatly reduces the magnitude of drift motions away from the vicinity of the X-point, where the accelerating component of the electric field is largest. Using plasma parameters consistent with flare observations, we obtain proton distributions extending up to gamma-ray-emitting energies (>1MeV). In some cases the energy distributions exhibit a bump-on-tail in the MeV range. In general, the shape of the distribution is sensitive to the model parameters.
Fletcher Lauren
Hamilton Brett
McClements K. G.
Thyagaraja Anantanarayanan
No associations
LandOfFree
Field-guided proton acceleration at reconnecting X-points in flares does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Field-guided proton acceleration at reconnecting X-points in flares, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Field-guided proton acceleration at reconnecting X-points in flares will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-585570