Synchrotron radiation was initially
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
There are many views on how synchrotrons and synchrotron
light developed. Below, I have written one of the views.
On 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
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 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)
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.
source facility (Synchrotron) is one of the few "third
generation" synchrotrons (most advanced)
and is among the five most powerful synchrotrons in the
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.