ORNL's High Flux Isotope Reactor prepares to make 'cold' neutrons

Oct 05, 2006
The Cold Neutron Source at ORNL's High Flux Isotope Reactor
The Cold Neutron Source at ORNL's High Flux Isotope Reactor has passed a major milestone with successful testing of its cooling system. Once fully operational, chilled neutrons will travel down the large tubes shown here to provide scientific analysis of various materials.

The High Flux Isotope Reactor at the Department of Energy's Oak Ridge National Laboratory has passed a major milestone in its quest to become one of the world's leading sources of "cold" neutrons for advanced scientific research.

Once fully operational, the reactor will combine with the laboratory's Spallation Neutron Source to make Oak Ridge the world's center for neutron sciences.

In tests this week, powerful refrigeration systems designed to cool the reactor's neutron beams to 20 K (minus 425° Fahrenheit) operated "just as we expected," said Kelly Beierschmitt, HFIR Executive Director.

"We now have a working cryogenic system to cool the neutrons at HFIR," Beierschmitt said. "This is a huge step toward completion of a truly world-class research facility, extending ORNL's leadership in the study of materials with neutron sciences.

"We will do systems testing and safety reviews over the next couple of months to prepare the reactor to resume routine operations. This is a very exciting time here at our reactor."

Neutrons are vital to research in physics, chemistry, engineering and other materials-related fields. At room temperature, they are ideal for use in special instruments to illuminate the atomic structure and dynamics of hard, dense materials.

Cooling them -- in this case to temperatures about 10 times colder than the South Pole -- slows their speed and lengthens their wavelength, which works better for studying the larger structural components of "soft" materials such as proteins and polymers or to analyze materials with certain magnetic properties.

HFIR's cold source will complement the capabilities of the recently completed Spallation Neutron Source, the world's premier neutron science facility.

While SNS also has cold-neutron capabilities, the continuous neutron flow from a reactor such as HFIR, as opposed to pulsed beams from accelerators like SNS, offers advantages for certain types of neutron experiments.

"ORNL will be unique in the world in having both high-intensity pulsed and continuous cold neutron sources," Steve Nagler, interim director of ORNL's Center for Neutron Scattering, said. "The neutron science community is eager to utilize these extraordinary capabilities, and we will soon be ready to provide them."

HFIR's continuous cold neutron source will rival the reactor at France's Institut Laue Langevin, generally considered as a world leader in the field, Nagler said.

Built in 1966, HFIR continues to be one of the nation's leading producers of isotopes for medical uses and other applications. The new cold neutron source is part of a $65 million DOE Office of Science-funded renovation that represents a major new direction for the reactor and revitalizes its role to the nation's science and research community.

"This is a significant milestone that allows the Office of Science to enhance our national laboratory system's infrastructure, enabling researchers to have additional capabilities to conduct experiments and produce world-class science," said Pat Dehmer, associate director of Basic Energy Sciences for DOE's Office of Science.

The fully instrumented HFIR will include 15 state-of-the-art neutron-scattering instruments, seven designed exclusively for cold neutron experiments; new computer control systems; and a new guide hall facility. Particularly prominent in the guide hall are the two new small-angle neutron scattering instruments, each terminating in a 70-foot long evacuated cylinder containing a large moveable neutron detector.

Source: Oak Ridge National Laboratory

Explore further: The unifying framework of symmetry reveals properties of a broad range of physical systems

add to favorites email to friend print save as pdf

Related Stories

Toward new precision in measuring the neutron lifetime

Feb 05, 2014

(Phys.org) —A team of PML scientists, with collaborators elsewhere, has achieved a five-fold reduction in the dominant uncertainty in an experiment that measured the mean lifetime of the free neutron (exceptionally ...

Newly invented shielding for stopping neutrons cold

Dec 09, 2013

When faced with the challenge of protecting sensitive scientific equipment and computers from radiation, engineers at the U.S. Department of Energy's Thomas Jefferson National Accelerator Facility decided ...

US teen designs compact nuclear reactor

Mar 01, 2013

Eighteen-year-old Taylor Wilson has designed a compact nuclear reactor that could one day burn waste from old atomic weapons to power anything from homes and factories to space colonies.

The nuclear reactor in your basement

Feb 19, 2013

How would you like to replace your water heater with a nuclear reactor? That's what Joseph Zawodny, a senior scientist at NASA's Langley Research Center, hopes to help bring about. It would tap the enormous ...

Industry and neutron science: Working to make a match

Sep 22, 2011

Industrial users are starting to eye the potential of neutron science for solving problems that can't be solved in any other way. At the same time, the Spallation Neutron Source and High Flux Isotope Reactor ...

Recommended for you

What time is it in the universe?

Aug 29, 2014

Flavor Flav knows what time it is. At least he does for Flavor Flav. Even with all his moving and accelerating, with the planet, the solar system, getting on planes, taking elevators, and perhaps even some ...

Watching the structure of glass under pressure

Aug 28, 2014

Glass has many applications that call for different properties, such as resistance to thermal shock or to chemically harsh environments. Glassmakers commonly use additives such as boron oxide to tweak these ...

Inter-dependent networks stress test

Aug 28, 2014

Energy production systems are good examples of complex systems. Their infrastructure equipment requires ancillary sub-systems structured like a network—including water for cooling, transport to supply fuel, and ICT systems ...

Explainer: How does our sun shine?

Aug 28, 2014

What makes our sun shine has been a mystery for most of human history. Given our sun is a star and stars are suns, explaining the source of the sun's energy would help us understand why stars shine. ...

User comments : 0