Bertbrockhouse&Spectrometer

Bert Brockhouse adjusting his triple-axis spectrometer at the NRU reactor of AECL, Chalk River, Ontario

CHIN

© 2001, CHIN. All Rights Reserved.


An innovative spectrometer was developed by Dr. Bertram N. Brockhouse at the Atomic Energy of Canada Laboratory in 1958. As a result of his research on the structure and forces acting on atoms in solids, Brockhouse won the Nobel Prize for Physics in 1994.

Access to the newly-opened NRU reactor at Atomic Energy of Canada allowed Brockhouse to study the properties of solids using a neutron beam coming from the reactor. With this apparatus, Brockhouse was able to measure:

• the forces between atoms in solids,
• magnetic forces on the atomic scale, and
• the motions of individual atoms in liquids.

The spectrometer consists of:

1. monochromator which selects neutrons of specific energy characteristics (axis
2. sample crystal mounted on a rotating base (an anti-aircraft gun bearing!) (axis
3. detector and recording apparatus (axis 3).
An innovative spectrometer was developed by Dr. Bertram N. Brockhouse at the Atomic Energy of Canada Laboratory in 1958. As a result of his research on the structure and forces acting on atoms in solids, Brockhouse won the Nobel Prize for Physics in 1994.

Access to the newly-opened NRU reactor at Atomic Energy of Canada allowed Brockhouse to study the properties of solids using a neutron beam coming from the reactor. With this apparatus, Brockhouse was able to measure:

• the forces between atoms in solids,
• magnetic forces on the atomic scale, and
• the motions of individual atoms in liquids.

The spectrometer consists of:

1. monochromator which selects neutrons of specific energy characteristics (axis
2. sample crystal mounted on a rotating base (an anti-aircraft gun bearing!) (axis
3. detector and recording apparatus (axis 3).

© 2001, CHIN. All Rights Reserved.

Brockhouse’s triple-axis spectrometer, mounted at one of the "windows" of the NRU nuclear reactor, allowed him to study crystals or condensed matter fluids in a new way. Experimenters could "select" neutrons of similar energy or "colour" (monochromatic) which then collide with the sample, for example, a "grown" aluminum crystal. By scattering neutrons (sub-atomic particles of high energy) off the nuclei of atoms held in the sample’s crystal structure, the direction of scatter and the speed with which the atoms move after a collision with a neutron can be measured.

This was the first of many such instruments used at research reactors around the world. The techniques developed by Brockhouse are used to study such topics as ceramic superconductors, catalytic exhaust cleaning, elastic properties of polymers and structures of viruses.
Brockhouse’s triple-axis spectrometer, mounted at one of the "windows" of the NRU nuclear reactor, allowed him to study crystals or condensed matter fluids in a new way. Experimenters could "select" neutrons of similar energy or "colour" (monochromatic) which then collide with the sample, for example, a "grown" aluminum crystal. By scattering neutrons (sub-atomic particles of high energy) off the nuclei of atoms held in the sample’s crystal structure, the direction of scatter and the speed with which the atoms move after a collision with a neutron can be measured.

This was the first of many such instruments used at research reactors around the world. The techniques developed by Brockhouse are used to study such topics as ceramic superconductors, catalytic exhaust cleaning, elastic properties of polymers and structures of viruses.

© 2001, CHIN. All Rights Reserved.

TripleAxisSpectrometer

The sample being studied is seen here on the rotating table of the spectrometer. To measure the characteristics of materials like crystals or metals by using a neutron beam source.

Made by Atomic Energy of Canada Ltd., Chalk River, ON,
Canada Science and Technology Museum
c. 1957-1961
951561
© 2001, CHIN. All Rights Reserved.


Learning Objectives

The learner will:
  • Identify and appreciate the way history and culture shape a society’s science and technology
  • Describe scientific and technological developments, past and present, and appreciate their impact on individuals and societies
  • Describe how Canadians have contributed to science and technology on the global stage

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