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RAP opportunity at National Institute of Standards and Technology     NIST

Absolute radioactive gas measurements spanning 9 orders of magnitude in activity


Physical Measurement Laboratory, Radiation Physics Division

opportunity location
50.68.21.C0345 Gaithersburg, MD

NIST only participates in the February and August reviews.


name email phone
Ryan P Fitzgerald 301-975-5597


Measurements of radioactive gases are critical in environmental monitoring, nonproliferation testing, and medical applications. NIST has been asked by multiple stakeholders to provide measurement traceability to the SI (unit Bq) by expanding on traditional gas counting capabilities and developing new methods to meet outstanding challenges. In particular, we seek to develop absolute assay the activity of radioactive gases (Kr, Xe, H) not only at the traditionally high levels (~ MBq) normally done by metrology institutes, but also at low levels (< mBq) needed to provide metrological traceability for environmental and nonproliferation measurements. Gas handling and dilution techniques will need to be developed to make measurements possible over the necessary activity ranges for the disparate applications, while maintaining traceability to the SI with low overall uncertainty (~ 0.1 %).

Longer-term plans include development of complementary absolute activity methods, such as coincidence counting and defined solid angle counting, as well as atom counting methods such as cavity ringdown spectroscopy. A potential scientific impact would be to combine atom counting with decay counting on the same sample to produce a novel measurement of half-lives, e.g. for radioactive dating.

key words
Radioactivity; Radiation; Gas counting; Radiation detection; Instrumentation


Citizenship:  Open to U.S. citizens
Level:  Open to Postdoctoral applicants


Base Stipend Travel Allotment Supplementation
$82,764.00 $3,000.00
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