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Reactor-Based Experiments

Samples

The research reactor provides a mixed-field environment composed of neutrons and photons.  We have several facilities that can be used for testing.  The size of your samples and the desired fluence will be used to determine which facility would best meet your needs.

When samples are irradiated in the reactor (as opposed to the cobalt facility), they have the potential to become radioactive.  It may be necessary to leave the sample at the Reactor Laboratory for some period following the irradiation before it can be returned to you.  If you have a license to possess radioactive materials, we would be able to return the sample to you earlier than if you do not.

Lead Time

Lead time will depend heavily upon the requested neutron fluence.  If it turns out to be a one-hour test, the lead time would be a couple of weeks.  We would have to do a safety analysis where we consider the makeup of the sample and what activity we expect to produce.  If it turns out to be a much longer test, the lead time could be a few weeks longer.  It would of course depend upon what we already had on our calendar.

Cost

The cost of the experiment will depend upon the desired total fluence, the amount of staff involvement, and the disposition of the samples following the experiment.  There are hourly usage rates for the reactor and for staff time, and charges for rad waste.  Staff time is used for completing the safety analysis, reactor pre-start and post-shutdown checkouts, experiment installation and removal, rad waste disposal, etc.

The reactor is operated on demand during normal business hours. The maximum operation time is seven hours in a day.

Short irradiations

We are unable to perform short exposures (i.e. a few minutes) in any of the facilities other than the pneumatic tube. The reactor takes ~25 minutes to start up from zero power and it takes ~4 minutes to shut down. We try to keep irradiations to at least 20 minutes so this ramp up and ramp down time doesn't become a significant portion of the fluence delivered. Short irradiations could consider using the pneumatic tube where a vacuum system inserts and extracts samples in sample carriers that have a 1.1-inch opening for precisely-timed irradiations.

As an alternative, we can reduce reactor power. The fluxes that are posted on the website are for a reactor power of 450 kW.  The lowest reactor power at which we can operate is 20 W, and the flux scales linearly with power. So a fluence of 1E11 could be delivered in the PIF at a reactor power of 25 W for 25 minutes. A fluence of 1E12 could be delivered in the PIF at 250 W for 25 minutes, and so on.

Multiple irradiations in any facility other than the pneumatic tube would need to be done on a separate days.  There are short-lived nuclides that are created in the samples and in the baskets that need to be allowed to decay before the basket and sample could be removed from the reactor.