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You are here: Science» Science Goals» Life Circles of Matter and Energy» Particle Acceleration» Continued

Particle Acceleration

How are particles accelerated to extreme energies producing shocks, jets and cosmic rays?

Color-coded X-ray image of the Tycho SNR

Color-coded X-ray image of the Tycho SNR: red corresponds to Fe L emission, green to Si K emission, and blue to 4-6 keV continuum emission. This is derived from the Chandra observations after smoothing with the IXO point-spread-function. Courtesy of John P. Hughes et al. Click the image for a larger view.

« Polarized X-rays are also expected from the shock waves produced by supernovae. These regions have long been thought to be sites for acceleration of cosmic rays and also to have magnetic fields. Many supernova remnants show hard X-ray spectra that indicate synchrotron emission by TeV electrons.The radiation from these electrons will be polarized. IXO will measure the strength and direction of the polarization as a probe of the magnetic field structure and particle distribution in the supernova shocks.

IXO will allow measurements of separate temperatures for electrons and for different ions, as well as Doppler widths and shifts. From these we will quantify the extent of electron heating; constrain non-Maxwellian components of the electron distribution (the lowest-energy cosmic rays); and identify the fraction of shock energy going to accelerated particles in remnants.

Selected References

A.M.Bykov, Yu.A.Uvarov, J.B.G.M.Bloemen, J.W. den Herder, J.S.Kaastra, "A Model of Polarized X-ray Emission from Twinkling Synchrotron Supernova Shells", MNRAS (in press), 2009. Download PDF

For more information, refer to IXO Astro 2010 Decadal White Papers: Starburst Galaxies: Outflows of Metals and Energy into the IGM, D. Strickland et al.

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