Nuclear Photonics: Gamma Rays Search For Concealed Nuclear Threats

These gamma rays, called MEGa-rays (for mono-energetic gamma rays), are made by using a beam of fast-moving electrons to convert laser photons (light at a lesser energy) into the gamma ray part of the spectrum.

The incoherent gamma rays can be tuned to a specific energy so that they predominantly interact with only one kind of material. A beam of MEGa-rays, for example, might be absorbed by the nuclear fuel uranium-235 while passing through other substances including the more common (but less dangerous) isotope uranium-238. That sort of precision opens the door to “nuclear photonics,” the study of nuclei with light.

“It is kind of like tunable laser absorption spectroscopy but with gamma-rays,” says Chris Barty of Lawrence Livermore National Laboratory, who will present on MEGa-rays at this year's Conference on Lasers and Electro Optics (CLEO: 2011, May 1- 6 in Baltimore) .

In the last couple of years, MEGa-ray prototypes have identified elements like lithium and lead hidden behind metal barriers. The next-generation of MEGa-ray machines, which should come on-line in a couple of years, will be a million times brighter, allowing them to see through thick materials to locate specific targets in less than a second.

Barty will present several MEGa-ray applications in use today and will describe the attributes of next-generation devices. Work is under way on a MEGa-ray technology that could be placed on a truck trailer and carried out into the field to check containers suspected of having bomb material in them. At nuclear reactors, MEGa-rays could be used to quickly identify how enriched a spent fuel rod is in uranium-235. They could also examine nuclear waste containers to assess their contents without ever opening them up. MEGa-ray technology might also be employed in medicine to track drugs that carry specific isotope markers.

Presentation ATuF2, “Mono-Energetic Gamma-rays (MEGa-rays) and the Dawn of Nuclear Photonics,” by Chris Barty is at 4:30 p.m. Tuesday, May 3.

CLEO: 2011 Program Information
CLEO: 2011 unites the fields of lasers and optoelectronics by bringing together all aspects of laser technology, from basic research to industry applications. The main broad topics areas at the meeting are fundamental science, science and innovations, applications and technology, and market focus. An exposition featuring 300 participating companies will be held concurrently with the scientific presentations.

Plenary Session keynote speakers include Donald Keck, retired vice president of Corning, talking about making the first low-loss optical fibers; James Fujimoto of MIT, talking about medical imaging using optical coherence tomography (OCT); Mordechai (Moti) Segev of the Technion-Israel Institute of Technology, speaking about the localization of light; and Susumu Noda of Kyoto University, talking about the control of photons in photonic crystals.

Online resources:

• Conference program: http://www.cleoconference.org/Conference_Program
• CLEO: Expo: http://www.cleoconference.org/exhibit_hall
• Press Center: http://www.cleoconference.org/media_center
• Plenary Session: http://www.cleoconference.org/Conference_Program
• Special Symposia: http://www.cleoconference.org/Conference_Program/symposia.aspx

• Conference Registration: http://www.cleoconference.org/registration

Press Registration
A Press Room for credentialed press and analysts will be located on-site in the Baltimore Convention Center, Sunday, May 1 – Thursday, May 5. Media interested in attending the conference should register online at http://www.cleoconference.org/media_center/mediaregistrationform.aspx or contact Angela Stark at 202.416.1443, astark@osa.org.
About CLEO
With a distinguished history as the industry's leading event on laser science, the Conference on Lasers and Electro-Optics (CLEO) and the Quantum Electronics Laser Science Conference (QELS) is where laser technology was first introduced. CLEO: 2011 will unite the field of lasers and electro-optics by bringing together all aspects of laser technology, with content stemming from basic research to industry application. Sponsored by the American Physical Society's (APS) Laser Science Division, the Institute of Electronic Engineers (IEEE) Photonics Society and the Optical Society (OSA), CLEO: 2011 provides the full range of critical developments in the field, showcasing the most significant milestones from laboratory to marketplace. With an unparalleled breadth and depth of coverage, CLEO: 2011 connects all of the critical vertical markets in lasers and electro-optics. For more information, visit the conference's website at www.cleoconference.org.