CCHPS Technical Meeting

November 2019

EXPLORING THE GAMMA LANDSCAPE: The future of low-level gamma-spectrometry

Presented by Dr Jonathan L. Burnett


Gamma-spectrometry is a powerful technique for making low-level nuclear measurements in support of research studies as varied as environmental monitoring to the nature of meteorites. Recent advancements in the functionality of detector electronics and computer performance are redefining the possibilities for radionuclide detection. Advanced multidimensional gamma-spectrometry systems capable of coincidence, anti-coincidence and delayed coincidence and coupled with other forms of radiation detection (α, β, X-ray) are becoming a viable option for modestly equipped radiometrology laboratories. Powerful multichannel analyzers (MCAs) that can provide precise nanosecond logging of detector events are enabling this transition. The simplest systems include surrounding a germanium (Ge) gamma-spectrometer with plastic scintillators to detect and reject cosmic background radiation. This can provide a mean background reduction of almost 80% and improvements in the minimum detectable activity (MDA) of 40-50%. Similar improvements are achievable using Compton suppression systems that surround the Ge with a sodium iodide (NaI) shield. More advanced systems combine detectors into arrays for radionuclide measurement based upon unique coincidence radiation signatures, and are capable of background reductions exceeding 99%. At Pacific Northwest National Laboratory (PNNL) an ultra-sensitive multidimensional gamma-spectrometer is being developed in an underground laboratory that combines these technologies to provide a world-class detection capability. Its ability to measure multiple radiation signatures will provide unprecedented detection possibilities and the opportunity for exploration of the gamma landscape.

Dr. Jonathan L. Burnett is a senior scientist at Pacific Northwest National Laboratory (PNNL) specializing in the detection of environmental radioactivity from natural, civil and military sources. Throughout his career, a focus has been on the detection of radionuclide signatures from nuclear explosive tests in support of the Comprehensive Nuclear-Test-Ban Treaty (CTBT). This has led to the development of a variety of advanced gamma-spectrometry systems for low-level radionuclide detection, including next-generation Compton suppression, cosmic veto and multi-dimensional gamma-spectrometry systems.


Thursday, November 14, 2019

Reservations are accepted until Tuesday, November 12.


5:45 – 6:30 PM Dinner & Social

6:30 - 7:15 PM Presentation


Olive Garden Catering

  • Grilled Chicken
  • Meatballs
  • Italian Sausage
  • Spaghetti & Fettuccine Pasta
  • Alfredo, Meat Sauce & Marinara
  • Salad
  • Fresh Baked Breadsticks
  • Mini-Desserts
  • Unsweetened Iced Tea, Water

$22.00 per person

NOTE: Members who do not cancel their RSVP by November 12, 2019 will be held responsible for the cost of attendance


Richland Community Center. 500 Amon Park Drive, Richland, WA 99352

Online Registration

Step 1: Fill out the online registration form

Step 2: Pay reservation fee online with a credit card, debit card, or PayPal; or at the event with a check or cash