University of North Texas

By Alyssa Yancey, News Promotions

If you were walking past the Physics Building last December, you might have noticed a strange scene: a 15,000 pound cylindrically-shaped, tan-colored can being lowered into the building’s basement by a 50 foot high crane.

The scene was the realization of the Ion Beam Modification and Analysis Laboratory’s (IBMAL) long-standing desire to relocate a National Electrostatic Corporation 9SH Linear particle accelerator. The IBMAL is one of the most sophisticated ion beam facilities in the country, and the recent installation of the 3 million volt particle accelerator will further expand laboratory capabilities.

The was originally given to UNT by Texas Instruments, when TI downsized Central Research Laboratories in Dallas. The six foot diameter by 14 foot long cylindrical tank of the accelerator was moved to the Physics Building basement from the Hickory Hall basement Dec. 9. The accelerator should resume operations by March.

The current configuration of IBMAL, which was established in 1986, makes it one of top ion beam labs at any university in the country. Floyd “Del” McDaniel, Regents Professor of physics, is director.

Above, from left, Duncan Weathers, associate professor of physics, Gary Glass, professor of physics, McDaniel and Bibhudutta Rout, assistant professor of physics.

So how does this work?

Protons, which are positively charged nuclei of hydrogen atoms, are produced and accelerated by the particle accelerator to a high rate of speed of about eight percent of the speed of light. A number of different ions can be produced and accelerated by this particle accelerator. The ions can then be used to characterize many different materials using atomic and nuclear reactions to determine the elemental composition or chemistry of the original sample.

The researchers also can implant ions into existing materials to alter the structure, and subsequently the properties, of the materials.

These tools can be used for a variety of purposes.

For instance, IBMAL has worked with the National Institutes of Health to analyze the elemental composition of cancer cells. The research team also measures the composition of the silicon wafers used in semiconductors to identify ways to produce more pure materials. The team is using the penetrating capabilities of the ions produced by their accelerators to study how to create materials that can absorb and emit light for use in renewable energy applications.

The Ion Beam Modification and Analysis Laboratory currently has four active linear particle accelerators, including the model 9SH 3 million volt linear Pelletron accelerator and a model 9SDH-2 Tandem Pelletron accelerator. The Tandem Pelletron can create ions from either a gas or solid state source; whereas, the 9SH produces ions from gas sources.

The 9SH Linear accelerator is a valuable addition to the lab because of the improved ability to produce a stable and controlled flow of positive ions from the device. This ability will allow researchers to focus the ion beams to 100 nanometer spot sizes or less, which makes both characterization and implantation into materials much more precise.

• Learn more: Ion Beam Modification and Analysis Laboratory.

(Photo by Gary Payne)