Reactor Experiments

Reactor Experiments

The MIT Reactor is ideally suited to experiments conducted inside the core of the reactor, and multiple long-term experiments can be conducted simultaneously. The reactor provides an irradiation environment very similar to that of a full-sized light-water reactor in a convenient compact area; this makes it ideal for the development and testing of materials and instrumentation.

For inquiries about specific in-core experiments, please contact David Carpenter. Additional details about in-core experiments can be found in the MITR User’s Guide.


Of the 27 fuel element positions in the MITR, three are dedicated to in-core experiments. These positions offer the highest neutron and gamma fluxes available. Additional spaces in and around the core tank offer further flexibility. Details about the MITR’s in-core experimental facilities can be found here. While specific experiment designs are based on user requirements, there are two commonly-used facilities available:

  • Pressurized water loop capable of mimicking the conditions of a pressurized water reactor or boiling water reactor core (up to 300°C and 10 MPa), and
  • Inert gas facility able to irradiate up to 900°C, typically with a helium/neon mixture.

Both of these facilities can accept a variety of samples, including sealed capsules (e.g. for irradiation of reactive materials requiring controlled atmospheres). Examples of some other recent in-core experimental facilities are:

  • 1400°C high-temperature irradiation facility,
  • Fueled irradiations with typical cladding and fuel centerline temperatures, and
  • 700°C fluoride salt facility with capture of tritium and condensates.

Reactor experiment

Instrumentation and Control

Precise control, monitoring, and data acquisition are central to an experiment’s operations. One of the important advantages of the MTIR over other reactors is the ability to instrument and actively monitor every experimental position. Each facility can monitor pressure, temperature, and chemistry parameters, in addition to the data acquisition needs of the experiment. Some examples of in-core sensors that have been used at the MITR are thermocouples, miniature neutron and gamma detectors, ultrasonic transducers, fiber-optic probes, potential-drop monitors, and ECP electrodes. Our staff will work with users to determine the most suitable arrangement and composition of instrumentation for each project.