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Mark Birkinshaw made the first detections of the Sunyaev-Zel'dovich effect, the change in brightness of the microwave background radiation caused by inverse-Compton scatterings on hot electrons in the X-ray emitting atmospheres of clusters of galaxies, and has continued to work on this topic, most recently by using combined radio and optical data to measure absolute distances, matter, and energy contents of high-redshift clusters.
He also works on the X-ray properties of the jets of radio galaxies and quasars. He was one of the team that reported the first detection of a quasar jet with the Chandra satellite, and has worked on the detections and interpretation of many other jets, with a particular interest in determining the energy spectrum of jet electrons as a function of postion, and hence of discovering new information about particle acceleration processes.
An infra-red image of NGC 6251 from the Spitzer satellite, with a superimposed radio contour. The jet is detected in the infra-red in several Spitzer bands, ad the combination of the radio, infra-red, optical, and X-ray data for this jet provides exceptional information on the spectrum of the radiating electrons.
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| Updated: 28-Sep-2005 | Mark Birkinshaw |
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