Research Capabilities

Nuclear reactors are unique in their ability to deliver a large amount of neutrons to a sample. The most common use of these neutrons is to transmutate a stable isotope into a radioactive isotope either for research, trace elemental analysis, or isotope production purposes.

Another unique property of nuclear reactors is the intense gamma radiation emitted from the core, which is unmatched by most other sources. Many things from the sterilization of medical tools to the study of radiation effects on electronic components can be accomplished with gamma radiation.

The nuclear science center is a large source of gamma radiation and neutrons but there are many different options to deliver these types of radiation to a sample.

Neutron Irradiations

Beam port

Mixed Field

Near the reactor, there is a huge gamma flux in addition to the neutron flux. Some of these gammas come directly from fission, while others come from decay products of fission. This mixed field is the most common form of irradiation we do. This means most of the samples we irradiate are resistant to damage from gamma radiation and the heat they generate when they interact with matter.

Some researchers wish to expose material to neutrons while minimizing the gamma radiation. Placing a gamma shield (lead) between the reactor and the sample stops most of the gamma radiation with little effect on the neutrons. We have a large irradiation cell to accept almost any size sample for this purpose.

Past users include the Texas A&M Cyclotron Institute, which used the fields for radiation-testing components.

Beam Port

 

Mixed neutrons for activation

Mixed Neutrons for activation - diagram

Fission provides neutrons of various energies. Often these energies have different uses. For example, thermal (slow or low-energy) neutrons are best for activation since most elements prefer absorbing slow neutrons. In the reactor flux, there are more thermal neutrons than fast, so we can use this flux for most activations.

The primary users for mixed neutron activation are

  • Industrial tracer companies
  • Oilfield services companies
  • Private research companies that use radioactive metallic parts to test for wear
  • Radioactive medical isotopes users


Pure thermal field

The NSC has a heavy water box that will provide a highly thermalized neutron spectrum.

Fast neutron flux

For some jobs such as argon dating and gemstone irradiation, fast neutrons are preferable to slow neutrons. For these jobs, the NSC has devices that filter out the thermal neutrons leaving just the fast neutrons. Users include geophysics departments at New Mexico Tech, the University of Minnesota and the University of Nevada-Las Vegas.

Gamma Irradiations

Reactor Gammas

The NSC can use the shutdown reactor to provide intense gamma radiation up to many MRad/hr, neutron-free, in the irradiation cell. If the reactor is operating, neutron absorbing material can be used to reduce the neutrons without adversely affecting the gamma radiation.

Users include

  • Texas A&M College of Veterinary Medicine
  • Texas A&M Department of Horticulture
  • Texas A&M Department of Soil and Crop Sciences


Lanthanum Source

The NSC has a large lanthanum (La) source that can provide a different energy spectrum than the reactor at lower levels.

Other Services

The NSC provides a place where researchers and industry partners can conduct a variety of experiments with radioactive materials -- ideal for organizations without the expertise or licenses necessary to handle and posses these materials. Previous users include various departments at Texas A&M and several private research institutions.

Neutron Activation Analysis

The NSC, individually or with the Center for Chemical Characterization and Analysis, uses neutron activation analysis to identify trace metals in various materials.

Previous users include:

  • Oil field services for quality control
  • Semiconductor manufacturers
  • Texas A&M Department of Entomology
  • Texas A&M Department of Animal Science
  • Texas A&M Department of Soil and Crop Sciences
  • Texas A&M Department of Oceanography

Motor
Neutron Radiography

Neutron Radiography has key advantages over other on-destructive testing methods because metals appear transparent and light element materials are opaque, and thus, is able to reveal the internal structure of an object, where x-rays are either scattered or absorbed. The simplest of neutron collimation devices is the pinhole aperture, and this consists of a pinhole in a strong neutron absorbing material. These include the Sӧller, straw, and honeycomb collimators. These advanced designs provide for enhanced beam parameters that result in higher beam luminosity, low beam divergence, and thus sharper images and quicker acquisition times.

Radioassay

The NSC houses a multi-million dollar counting lab with four high-purity germanium detectors. This lab gives us the ability to detect and identify extremely small amounts of radioactive material, ideal for various applications.