Science Education Home Home Teachers Students Games Videos VA SOL Programs
Reading Comprehension Passages
Select New PassageClear This Passage

Looking for Quarks Inside the Atom

In the late 1960's, three scientists ran some accelerator experiments to study the nucleus at the of the atom. They ran the experiments because they wanted to know more about the structure of the . They found that the protons and neutrons in the nucleus are made of quarks. The discovery of raised new questions about the nucleus.

The three scientists are Richard Taylor, Henry Kendall and Jerome Friedman. They did their experiments from 1967 to 1973 in California at the Stanford Linear Accelerator Center, called SLAC for short. These scientists won the 1990 Nobel Prize in Physics, one of the world's greatest honors for .

In the 1960's some scientists, like Murray Gell-Mann, were beginning to think that each nucleon might really be made up of even smaller particles. Gell-Mann even had a name for the smaller . He called them quarks.

Taylor, Kendall and Friedman used beams of high-energy electrons at SLAC to explore deep inside atoms. Inside the two mile long accelerator the electrons gained energy as they moved along in a beam almost as fast as light. At the end of the accelerator, some hydrogen was the target for the electrons. Sometimes an electron would into the proton inside of the hydrogen atoms. These crashes were far too tiny to see directly or even with a microscope. The three experimenters used spectrometers to what happened.

Each spectrometer consisted of huge electromagnets, about the of a bus, and some detectors. When electrons crash into a target nucleus, a spectrometer measures their angles and energies as they bounce away. The electrons were not striking solid protons. They were striking vibrating clusters of quarks. Each proton is a cluster or three ; each neutron is too.

This new discovery led to new questions. Experiments at Jefferson Lab will answer new about quarks and nuclei. That's how scientific research works. There is always something new to find out!

In fact, that's why Alfred B. Nobel started the Nobel in 1901. In December, 1990, Taylor, Kendall and Friedman went to Stockholm, Sweden, to receive their Nobel Prize in Physics. The three winners shared not only the honor of the Nobel, but the that comes with it: $710,000.

Check my answers!

Citation and linking information

For questions about this page, please contact Steve Gagnon.