Imagine the Universe!
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Spectrum Contrast - Thermal vs. Cosmic Rays

These two spectra show the difference between thermal and synchrotron emission. In the thermal spectrum (top), many narrow features, or lines, are apparent. These lines represent transitions between two distinct energy states in a particular atom. It is possible to identify what element is responsible for the emission from the energy of the line. In contrast, the spectrum from synchrotron emission does not show these narrow features, but appears as a straight line. There is more flux at lower energies.

spectral analysis of Cas A (

X-ray spectrum of Cas-A (

SN 1006 spectra (

X-ray spectrum of SN 1006 (

Return to the Cosmic Rays page

Imagine the Universe is a service of the High Energy Astrophysics Science Archive Research Center (HEASARC), Dr. Alan Smale (Director), within the Astrophysics Science Division (ASD) at NASA's Goddard Space Flight Center.

The Imagine Team
Acting Project Leader: Dr. Barbara Mattson
All material on this site has been created and updated between 1997-2012.

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