TESLA Brochure - ACFA Joint Linear Collider Physics and Detector ...

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“To see something new, you must
make something new”
G. C. Lichtenberg
1 Wilhelm Conrad Röntgen
discovered and gave
X-rays their name in 1895.
In 1901,he was honored
for his discovery with the
award of the first Nobel
prize for Physics.
2 Hand of history:
One of the first radiographs
made by Röntgen.
The image,from November
1895,shows his wife
Bertha’s hand.
3 Building the X-ray laser:
The structure being assembled
is an undulator—an
arrangement
consisting of many magnets.The
undulator will
be used to produce laserlike
X-ray radiation.
Even calculating a simple property of a material—its melting point, for example—is
highly complex and has only proved possible in a few, very basic cases.
Factors like temperature and pressure make things even more complicated. So
too does the fact that different substances are mixed to imbue materials with
desirable properties,such as low weight,hardness,resistance to high temperatures,transparency,low
electrical resistance or a low-abrasion surface.
Take a “simple” process such as friction. What actually happens here at the
atomic level? As is so often the case, new experiments make it necessary to rethink
the known theory.The phenomenon of superconductivity,which was discovered
in 1911 and theoretically explained in 1957, is a prime example. Superconductivity
seemed under control until the discovery of high-temperature
superconductors forced physicists back to the drawing-board:the existing theory
did not predict the loss of electrical resistance at such high temperatures.
Experience shows that new experiments are required in order to describe
known phenomena more exactly and discover new ones. Proceeding upon this
basis will help us secure a long-term answer to a crucial question: How can we
use the world’s resources in the most appropriate manner?
Discovered over 100 years ago, X-rays enable us to penetrate the secrets of
matter and molecular structure. This is because the wavelengths of X-rays approximate
to the distance between atoms in solid bodies. In fact, the use of
X-rays has produced many a breakthrough in the natural sciences in the 20th
century. And this powerful tool continues to play a key role in research and
medical and industrial applications. Over the last 20 years, the intense X-rays
produced by particle accelerators in the form of synchrotron radiation have advanced
research substantially. By the same token, development of a free electron
laser would open up a completely new dimension in our understanding.
Using the extremely short and intense beams of X-ray light such a laser generates,it
would even be possible to “film”atomic processes.
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