ORNL's research reactor revamps veteran neutron scattering tool

October 19, 2010
The Cold Triple Axis spectrometer, now in commissioning at Oak Ridge National Laboratory's High Flux Isotope Reactor, moves by way of air pads on an epoxy surface known as the "dance floor."

The Cold Triple Axis spectrometer, a new addition to Oak Ridge National Laboratory's High Flux Isotope Reactor and a complementary tool to other neutron scattering instruments at ORNL, has entered its commissioning phase.

The CTAX uses "cold" neutrons from the HFIR cold source to study low-energy magnetic excitations in materials. Cold neutrons are slower than their "thermal" neutron counterparts, and thus perfect for probing low-energy dynamics.

The instrument, which moves by way of air pads on an epoxy surface known as the "dance floor," is one of only two of its kind in the United States. Following commissioning, it will be available for users this coming spring.

"Neutrons have unique properties that make them ideally suited to study the complex atomic-scale interactions that govern the macroscopic physical and chemical properties of materials," said Jaime Fernandez-Baca, leader of the Triple Axis group.

The types of materials studied by instruments like CTAX and the new Cold Neutron Chopper Spectrometer (CNCS) at ORNL's Spallation Neutron Source (SNS) include energy and electronic technology-related materials such as those used in solar cells, data storage, batteries, superconductors and materials with potential applications in electronic devices.

"While the CNCS at SNS provides snapshots of broad ranges of energy and wave vector space, the CTAX at HFIR allows for a very detailed and focused view of small regions of this space," Fernandez-Baca said. "With the information provided by these two types of instruments, we get a more thorough view of the materials being studied, enabling us to design and make novel materials to meet technological challenges."

The original CTAX instrumentation was developed at Brookhaven National Laboratory by a Japanese team as part of the U.S.-Japan Cooperative Neutron Scattering program. DOE's Office of Science funded its relocation and modification for use at ORNL.

CTAX offers better energy and momentum resolution than most of the other neutron scattering instruments, as well as the flexibility to observe materials under a variety of sample environmental conditions like high and low temperatures, high pressures and magnetic and electric fields. The use of polarizing neutrons to study magnetic excitations will also be implemented at CTAX.

As part of the U.S.-Japan agreement 25 percent of time on CTAX will be used by ORNL and Japanese researchers for experiments performed under this collaboration. The greater 75 percent of use will be allocated to general users from university and research institutions.

Explore further: 'Cold linac' commissioning major step for ORNL's Spallation Neutron Source

Related Stories

Recommended for you

Algorithm ensures that random numbers are truly random

June 24, 2016

(Phys.org)—Generating a sequence of random numbers may be more difficult than it sounds. Although the numbers may appear random, how do you know for sure that they don't actually follow some complex, underlying pattern? ...

Possibility of new particle discovery at LHC fading

June 24, 2016

The physics community is apparently starting to lose its buzz over the possibility of the discovery of a new particle by researchers working at the CERN LHC facility near Geneva. As more data is studied, it appears more and ...

Probing giant planets' dark hydrogen

June 23, 2016

Hydrogen is the most-abundant element in the universe. It's also the simplest—sporting only a single electron in each atom. But that simplicity is deceptive, because there is still so much we have to learn about hydrogen.

Important milestone reached on road to a redefined kilogram

June 21, 2016

In a secure vault in the suburbs of Paris, an egg-sized cylinder of metal sits in a climate-controlled room under three glass bell jars. It is the mass against which all other masses in the world are measured - by definition ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.