History of Synchrotron Light


Synchrotron radiation was initially a nuisance, sapping energy from circulating electron beams and upsetting calculations. Fortunately physicists learned that the fan of synchrotron radiation "waste" from high energy electron rings could be used to probe the structure of a wide range of samples.

There are many views on how synchrotrons and synchrotron light developed. Below, I have written one of the views.

The first seen Synchrotron radiationOn April 24, 1947, Herb Pollock, Robert Langmuir, Frank Elder, and Anatole Gurewitsch saw a gleam of bluish-white light emerging from the transparent vacuum  tube of their new 70MeV  electron synchrotron at General Electric's Research Laboratory, Schenectady, New York: Synchrotron radiation had been seen. Here is a picture of the first synchrotron radiation seen. The first seen synchrotron radiation is indicated by arrow in the picture on the left.

(The first seen Synchrotron radiation)

But the idea of synchrotron light goes  as far back as the 19th century. A French physicist Alfred Lienard of the Ecole des Mines in Paris described the concept of retarded potentials  in the calculation of the effects due to the motion of charged particles, and worked out a basic theory of what is now known as synchrotron radiation. Lienard's theory is still followed in modern physics text books today. This work was supplemented by Emil Wiechert, so the formalism is generally known as the Lienard-Wiechert potentials. Lienard's paper appeared just after the discovery of the electron by J. J. Thomson exactly one hundred years ago at Cambridge. However an embryonic idea of synchrotron radiation can be traced farther back than Lienard's paper to 1867, to Ludwig Lorenz.

The brightness of light beam produced by first, second, and third generation Synchrotrons
(The brightness of light beam produced by first, second, and third generation Synchrotrons)


The next major development of synchrotron radiation theory came in 1908 from G. A. Schott, first as an student of Cambridge, then at Aberystwyth, Wales in a prizewinning paper about mechanical reactions of electromagnetic radiation. The idea of synchrotron radiation lay dormant for a few decades before synchrotron radiation was seen April 24, 1947. From there, continuous advancement of synchrotrons  occurred and the brightness of the light produced also kept increasing. Third generations synchrotrons are the most advanced ones today and the radiation produced by them is  exceptionally brighter than the first seen radiation (see picture below). 

Today's Synchrotron radiation beam
(Today's Synchrotron radiation beam)

Canadian light source building, Saskatoon, SK

(Canadian light source building, Saskatoon, SK)


Today, there are more than fifty synchrotrons worldwide but the facilities vary in their capacity and the brightness of the light they produce. Canadian light  source facility (Synchrotron) is one of the few "third generation" synchrotrons (most advanced)  and is among the five most powerful synchrotrons in the world. 


The top three world's most powerful synchrotrons are "Advanced Photon Source (APS)" in the United States of America, "European Synchrotron Radiation Facility (ESRF)" and the "SPring-8" facility in Japan. The SPring-8 synchrotron is the most powerful and the biggest synchrotron in the world.



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