University of Illinois at Urbana-Champaign

Department of Astronomy

Three wavelength image of the supernova remnant Cassiopeia A, the remains of a star that exploded about 1680. The x-ray image (shown in green) represents very hot gas at about 10 million Kelvin heated by the shock waves accompanying the supersonic expansion of exploding star moving out into its surroundings at about 20 million miles per hour. The red represents optical emission from cooler, denser clumps of gas at about 10 thousand Kelvin immersed in the hotter gas under pressure balance. The blue is radio synchrotron emission from relativistic electrons accelerated by the strong magnetism of this supernova remnant. By studying all three together we can learn in detail how the material expands and interacts with its surroundings.


John R. Dickel


Professor
Ph.D., University of Michigan, 1964
johnd@astro.uiuc.edu


I study supernova remnants both observationally and theoretically to detail the interaction of the expanding blast with the surrounding interstellar medium. By using radio, optical, infrared, and x-ray wavelengths, my colleagues and I can investigate all the various components of the surroundings to see how clumping and irregularities affect the expansion. 

Selected Publications:

Klinger, R. J., Dickel, J. R., Fields, B. D., and Milne, D. K. 2002, 
``A Peculiar Linear Radio Feature in the Supernova Remnant N206,'' 
AJ, 124, 2135

Dickel, J. R. and Wang, S. 2004, ``Peculiar Synchrotron Spectra in 
Pulsar Wind Nebulae,'' in Young Neutron Stars and their Environment, 
IAU Symposium, 218, 221

Williams, R., Chu, Y.-H., Dickel, J., Gruendl, R., Shelton, R., Points, S., 
and Smith, R. C. 2004, ``Supernova Remnants in the Magellanic Clouds. IV. 
X-Ray Emission from the Largest Supernova Remnant in the Large Magellanic 
Cloud,'' ApJ, 613, 948

Dickel, J., McIntyre, V., Gruendl, R., and Milne, D. 2005, ``A 4.8 and 
8.6 GHz Survey of the Large Magellanic Cloud. I. The Images'', AJ, 129, 790

Gaensler, B. M., Haverkorn, M., Staveley-Smith, L., Dickey, J. M., 
McClure-Griffiths, N. M., Dickel, J. R., and Wolleben, M. 2005, 
``The Magnetic Field of the Large Magellanic Cloud Revealed Through 
Faraday Rotation,'' Science, 307, 1610