The McMaster Nuclear Reactor industrial hotcell houses a 10 kCi (370 TBq) Cobalt-60 source. Work is conducted via manipulators (mechanical arms) behind a one meter thick lead and oiled lined glass window. The facility includes a small air-lock system providing passage to the reactor pool. In addition, a large access door at the rear of the facility allows for movement of large pieces of equipment; access ports for instruments are also available. A variety of work is done in the hot cell, ranging from sterilization to nuclear dating to instrument calibration.

At McMaster University’s Nuclear Operations and Facilities, our unique combination of infrastructure, knowledge, and people enables us to offer our customers far more than simply access to facilities. We have the skills and experience to evaluate, implement, and actualize solutions to complex research problems, while maintaining the high standards of quality that our customers have come to rely upon. We have strength and experience in numerous research areas including: radiochemistry development, process chemistry, manufacturing development, separation science, project planning, etc. Please contact reactor@mcmaster for more information.

Delayed Neutron Counting (DNC), is most commonly used for determining uranium content in soil samples for the uranium mining industry. A non-destructive technique, it therefore can be used for expensive or irreplaceable samples such as archaeological artifacts.

Unlike of the lighter elements in the Periodic Table, when uranium absorbs a neutron, the neutron capture event is followed immediately by nuclear fission. As the uranium atom splits, it ejects an average of 2.8 neutrons per fission; by quantifying (counting) the ejected neutrons, the amount of uranium initially present in the sample can be determined.

To access this service, please submit an Access Request Form or contact reactor@mcmaster.ca.

The short half-life of ²⁰F (11s) makes for problematic analysis using traditional techniques. By using the rabbit pneumatic system, a short activation and decay time is used in order to analyze short-lived isotopes without interference. Fluorine analysis is often used to determine the fluorine content in polymers and other materials.

To access this service, please submit an Access Request Form or contact reactor@mcmaster.ca.

Nuclear Operations & Facilities houses a wide variety of high-purity germanium (HPGe) detectors used to measure gamma radiation emitted by radionuclides. Germanium detectors are semiconductor diodes having a p-i-n structure in which the intrinsic (I) region is sensitive to ionizing radiation, particularly x-rays and gamma rays.

These detectors can be used in conjunction with the various neutron activation analyses or as a stand-alone service.

For more information about HPGe detectors or gamma counting services, please contact reactor@mcmaster.ca.

There are 3 distinct hotcell facilities at Nuclear Operations and Facilities:

1. Centre for Advanced Nuclear Systems
   • A suite of custom designed, fabricated and installed hot cells with 5 separate workstations for receiving, machining and waste handling, sample preparation, mechanical testing and optical microscopy examination of irradiated material samples.
2. Large Application Industrial Hotcell
   • Contains the 10kCi Cobalt-60 source for applications, ranging from sterilization to nuclear dating to instrument calibration.
3.  Pharmaceutical Grade Hotcell
   • Located in the HLLF, access to a pharmaceutical grade hot cell is available for small-scale radioactive work.

The McMaster Alignment Diffractometer (MAD) is a general purpose triple-axis instrument that can be used to measure large angle neutron diffraction from samples in single crystal, polycrystalline, and powder form. It is primarily used for sample alignment and the evaluation of crystal quality. However, more advanced characterization measurements (determination of crystal structure, studies of phase transitions, inelastic neutron scattering) may be available upon request.

The McMaster Small Angle Neutron Scattering beamline (MacSANS) is a state-of-the-art instrument that will be used to measure neutron diffraction in the small angle regime (< 4 degrees). This low angle scattering provides detailed information about the nanoscale structure of materials, for lengthscales ranging from ~0.5 to 125 nm. MacSANS will be used to study a broad range of nanostructured materials, including polymers, biological membranes, metals and alloys, exotic magnets, and high temperature superconductors. This instrument is currently under construction.

Neutron radiography is a non-destructive technique for photographing the interior structure of solid objects. While radiography conceptually similar to conventional X-ray radiography, neutrons are attenuated by many light elements including hydrogen, boron and lithium but penetrate heavier materials such as metals: this is a direct contrast to X-rays, which are absorbed by heavier elements but cannot detect many lighter elements. Neutron and X-ray radiography are therefore considered complementary techniques for the visualization of the interior structures.

For commercial Neutron Radiography services please contact N-Ray Services Inc..

Argon-39/Argon-40 Method  

Argon-39/Argon-40 dating is the most widely used variant of nuclear dating due to its accuracy, the small sample size required and the wide sample age range for which it is valid. The initial step in the dating process is the irradiation of the geological sample in a neutron flux to convert a portion of the the naturally occurring stable isotope K-39 to Ar-39, a radioisotope with a moderate half-life of 269 years. Another isotope of argon, Ar-40, will also be present in the sample as the decay product of the naturally occurring long-lived radioisotope K-40 with a half life of 1,280,000,000 years. The age of the sample can be determined indirectly by measuring the ratio of Ar-39:Ar-40 via mass spectrometry.

McMaster Nuclear Reactor is well-suited for use as a neutron source for the 39-Argon/40-Argon dating technique because of its near-optimal fast neutron flux, the convenience and flexibility of the irradiation facility, and the relatively low sample heating resulting from its water-cooled design. Since the optimum irradiation period depends on the age of the samples, it is more convenient and cost-effective to use a number of small capsules irradiated for differing lengths of time than to use the large capsules required in many other facilities.

EPR Method

EPR dating is an alternative to nuclear dating that combines a type of molecular spectroscopy with MNR’s Cobalt-60 source. Electron Paramagnetic Resonance (EPR) spectroscopy is a method of monitoring the electronic configuration or spin state of a paramagnetic molecule or lattice. A sample is placed in an external magnetic field that aligns the electron spins, and a microwave radiation source is applied over a range of frequencies. Absorption of microwaves will occur when the energy of the radiation matches the energy required to induce a spin transition (“spin flip”) in the sample. This resonance absorption is directly proportional to the population of unpaired electrons in that particular energy state.

Exposure of materials to naturally occurring ionizing radiation (e.g. uranium, thorium, plutonium) over geological time causes the formation of paramagnetic defects in the crystal lattice that can be observed by EPR spectroscopy. Using an “additive dose” method of dating, a sample is deliberately exposed to gamma radiation using, for example, the Co-60 source housed at MNR, to examine the dose-response relationship between the applied radiation field and the extent of the paramagnetic defects. From this information, it is possible to extrapolate the dose a particular sample has received over time due to naturally occurring radiation, and therefore the age of the sample.

Materials suitable for EPR dating analysis include those containing apatite, aragonite, calcite, hydroxyapatite or silicate-based minerals. This method of dating has been applied extensively for samples of bones and teeth, fossilized organisms, volcanic and sedimentary rocks and geological deposits of ages ranging from 5,000 to 1,000,000 years.

For post-irradiation analysis, various facilities and equipment can be used spanning multiple locations serviced and maintained by Nuclear Operations & Facilities.

To access this service, please submit an Access Request Form or contact reactor@mcmaster.ca.

Prompt Gamma Neutron Activation Analysis, which uses the “prompt” gamma rays emitted during neutron capture, rather than the gamma rays that are emitted as the resulting radioisotope undergoes decay, is used in order to determine elemental composition; PGNAA is particularly useful for quantifying boron, cadmium, and certain lanthanoids (Eu, Gd, Sm).

To access this service, please submit an Access Request Form or contact reactor@mcmaster.ca.

Due to intrinsic nature of radioactive isotopes always emitting gamma rays at specific energies and intensities, the radioisotopes present, and hence the parent chemical element(s) present in a sample can be determined quantitatively using “Short-Lived Neutron Activation Analysis” (SLNAA).

To access this service, please submit an Access Request Form or contact reactor@mcmaster.ca.

The Taylor Source is a unique large volume, high dose-rate Cs-137 source, commonly used to examine the effects γ-radiation on living systems. The source can provide a variety of doses and dose rate irradiations. In recent years, approximately two dozen researchers have primarily used the Taylor source to study the effects of low doses of radiation at the cellular and molecular level.

The Taylor Source has been used increasingly over the past 5 years, support various research groups in radiation protection regulations, environmental science, cancer biology, healthcare practices, and nutrition.

The Technical Services team provides essential engineering support for ancillary groups within Nuclear Operations & Facilities including Iodine-125 production, radioisotope development, quality assurance, and reactor operations.  Major projects have included the installation, set-up and maintenance of data collection systems for the Centre for Neutron Activation Analysis and the design, construction and commissioning of the apparatus for the large-scale production of Iodine-125. Smaller initiatives include the design and fabrication of customized research equipment and handling tools for individual researchers.

With access to a considerable number of resources, including a high vacuum system, residual gas analyzer, bake-out equipment, an orbital welding system and various electronic test instruments, the Technical Services team is able to provide the following services:

Design & Fabrication of items including:

• Glove boxes, ventilated enclosures
• Electrical/Electronic interfaces
• Software (control & acquisition)
• Filtration Systems (housings, cartridges)
• Handling tools
• Gas Handling/Vacuum Systems

Testing & Calibration

• Pneumatic (Pressure) Testing
• Helium Leak Testing
• Residual Gas Analysis
• General Conformance (visual inspections)
• Calibration (torque wrenches, vacuum gauges, temperature probes)

Materials Preparation & Conditioning:

• Degreasing (Solvent based)
• Critical Cleaning (Ultrasonic w/ low residue agents)
• Sterilization (MNR Hot Cell using 60Co source)
• Temperature Cycling
• Electro-polishing (stainless steel)

General Repairs

• Vacuum Equipment (Diffusion, Rotary vane & diaphragm pumps)
• Radiation Detectors (HPGe Detectors & associated electronics)
• Electrical/Electronic Equipment

Commissioning (according to established procedures and/or guidelines):

• Isotope production equipment
• Irradiation facilities
• Electronic control and acquisition systems

The Technical Support team has expertise in the following areas:

• Electrical/Electronic Design (analog & digital)
• Data Acquisition (computer hardware & software)
• Fluid/Pneumatic Systems
• Ventilation & Filtration
• Cryogenics
• High Vacuum
• Orbital Welding (300 Series Stainless)
• Beam port experience

For questions regarding contract technical services please contact us at reactor@mcmaster.ca