The application of full spectrum analysis to NaI(Tl) gamma spectrometry for the determination of burial dose rates

Minqiang Bu, Andrew S. Murray, Myungho Kook, Jan Pieter Buylaert, Kristina J. Thomsen

Research output: Chapter in Book/Report/Conference proceedingArticle in proceedingsResearchpeer-review

39 Downloads (Pure)

Abstract

In this study, we explored the potential of a NaI(Tl) scintillator-based gamma spectrometer for the accurate determination of burial dose rates in natural geological samples using a full spectrum analysis (FSA) approach. In this method, an iterative reweighted least-square regression is used to fit calibration standard spectra (40K, and 238U and 232Th series in equilibrium) to the sample spectrum, after subtraction of an appropriate background. The resulting minimum detection limits for 40K, 238U, and 232Th are 4.8, 0.4 and 0.3 Bq·kg-1, respectively (for a 0.23 kg sample); this is one order of magnitude lower than those obtained with the three-window approach previously reported by us, and well below the concentrations found in most natural sediments. These improved values are also comparable to those from high-resolution HPGe gamma spectrometry. Almost all activity concentrations of 40K, 238U, and 232Th from 20 measured natural samples differ by ≤5% from the high resolution spectrometry values; the average ratio of dose rates derived from our NaI(Tl) spectrometer to those from HPGe spectrometry is 0.993 ± 0.004 (n=20). We conclude that our scintillation spectrometry system employing FSA is a useful alternative laboratory method for accurate and precise determination of burial dose rates at a significantly lower cost than high resolution gamma spectrometry.
Original languageEnglish
Title of host publicationConference Proceedings of the 5th Asia Pacific Luminescence and Electron Spin Resonance Dating Conference
Number of pages10
PublisherSciendo
Publication date2021
Pages161-170
DOIs
Publication statusPublished - 2021
Event 5th Asia Pacific Luminescence and Electron Spin Resonance Dating Conference - Beijing, China
Duration: 15 Oct 201817 Oct 2018

Conference

Conference 5th Asia Pacific Luminescence and Electron Spin Resonance Dating Conference
Country/TerritoryChina
CityBeijing
Period15/10/201817/10/2018
SeriesGeochronometria
Number1
Volume48
ISSN1733-8387

Keywords

  • NaI(Tl) detector
  • Scintillation gamma spectrometry
  • Full spectrum analysis (FSA)
  • Minimum detection limit (MDL)
  • Burial dose rate measurement
  • OSL dating

Fingerprint

Dive into the research topics of 'The application of full spectrum analysis to NaI(Tl) gamma spectrometry for the determination of burial dose rates'. Together they form a unique fingerprint.

Cite this