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A joint spectral analysis of some Chandra ACIS X-ray data and MolongloObservatory Synthesis Telescope radio data was performed for 13 small regionsalong the bright northeastern rim of the supernova remnant SN 1006. These datawere fitted with a synchrotron radiation model. The nonthermal electronspectrum used to compute the photon emission spectra is the traditionalexponentially cut off power law, with one notable difference: The power-lawindex is not a constant. It is a linear function of the logarithm of themomentum. This functional form enables us to show, for the first time, that thesynchrotron spectrum of SN 1006 seems to flatten with increasing energy. Theeffective power-law index of the electron spectrum is 2.2 at 1 GeV (i.e., radiosynchrotron-emitting momenta) and 2.0 at about 10 TeV (i.e., X-raysynchrotron-emitting momenta). This amount of change in the index isqualitatively consistent with theoretical models of the amount of curvature inthe proton spectrum of the remnant. The evidence of spectral curvature impliesthat cosmic rays are dynamically important instead of being "test" particles.The spectral analysis also provides a means of determining the criticalfrequency of the synchrotron spectrum associated with the highest-energyelectrons. The critical frequency seems to vary along the northeastern rim,with a maximum value of 1.1e17 (0.6e17 - 2.1e17) Hz. This value implies thatthe electron diffusion coefficient can be no larger than a factor of ~4.5-21times the Bohm diffusion coefficient if the velocity of the forward shock is inthe range 2300-5000 km/s. Since the coefficient is close to the Bohm limit,electrons are accelerated nearly as fast as possible in the regions where thecritical frequency is about 1.0e17 Hz.

Evidence of a Curved Synchrotron Spectrum in the Supernova Remnant SN 1006