| Description: | It has been long known that supernova remnants (SNRs) emit synchrotron radiation in the radio, but only since 15 years do we know that the youngest SNRs also emit synchrotron radiation in X-rays. The diagnostic power of the X-ray synchrotron radiation is large, as the emitting electron lose their energy fast unless the magnetic field is weak. Therefore, if we detect X-ray synchrotron radiation we know that the electron have recently been accelerated, or the magnetic field must be low. In this talks I will review the latest results on X-ray synchrotron radiation from SNRs, which has enabled us to estimate magnetic fields, and also suggest that SNR reverse shocks, heating supernova material, can accelerate electrons. I will conclude the talk by also discussing H-alpha emission from shock fronts, which offers the opportunity to measure the proton temperature. Combining this with shock velocity measurements and X-ray synchrotron emission leads to a better understanding of overall particle acceleration properties, including ion acceleration.
Image above: The combined image from the Chandra and XMM-Newton X-ray observatories of RCW 86 shows the expanding ring of debris that was created after a massive star in the Milky Way collapsed onto itself and exploded. Both the Chandra and XMM images show low energy X-rays in red, medium energies in green and high energies in blue. The Chandra observations focused on the northeast (left-hand) side of RCW 86, and show that X-ray radiation is produced both by high-energy electrons accelerated in a magnetic field (blue) as well as heat from the blast itself (red). More information can be found here: http://chandra.harvard.edu/photo/2006/rcw86/
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