Source term estimation of multi-specie atmospheric release of radiation from gamma dose rates

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985556%3A_____%2F18%3A00493137" target="_blank" >RIV/67985556:_____/18:00493137 - isvavai.cz</a>

Result on the web

<a href="http://dx.doi.org/10.1002/qj.3403" target="_blank" >http://dx.doi.org/10.1002/qj.3403</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1002/qj.3403" target="_blank" >10.1002/qj.3403</a>

Result language

angličtina

Original language name

Source term estimation of multi-specie atmospheric release of radiation from gamma dose rates

Original language description

Determination of a source term of an accidental release of radioactive material into the atmosphere is very important for evaluating emergency situations and their consequences. However, knowledge of the source term and its composition is typically vague and uncertain. One possible way to obtain the source term is inverse modeling in which an atmospheric transport model is combined with field measurements. The most accessible measurements are those from gamma dose rate (GDR) detectors. However, GDR measurements represent a sum of contribution from all nuclides from both plume and deposition which makes the problem particularly difficult. The same difficulty arises when the measurements can not distinguish contribution from another species in the release, such as nuclides attached to different particle sizes. We propose a Bayesian method for recovery of the source term from GDR measurements where a priori knowledge on ratios of different species is given in the form of bounds. This knowledge is incorporated into the model of covariance matrix of the source term. The Bayesian methodology allows to handle uncertain knowledge on the nuclide ratios as well as unknown temporal correlations of the source term. We evaluate and compare the proposed method with other state-of-the-art methods on a twin experiment of a non-stationary release of 16 nuclides from the Czech nuclear power plant Temelin being registered by the Austrian GDR monitoring network. Real-world validation of the approach is performed on the latest measurements of concentration and deposition of caesium-137 from the Chernobyl accident, where we estimate composition of the source term from different particle sizes (species). The estimated source term is in very good agreement with previously reported results and the calculated species ratios are supported by the available observations.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

10103 - Statistics and probability

Project

<a href="/en/project/7F14287" target="_blank" >7F14287: Source-Term Determination of Radionuclide Releases by Inverse Atmospheric Dispersion Modelling (STRADI)</a><br>

Continuities

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Publication year

2018

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Quarterly Journal of the Royal Meteorological Society

ISSN

0035-9009

e-ISSN

—

Volume of the periodical

144

Issue of the periodical within the volume

717

Country of publishing house

GB - UNITED KINGDOM

Number of pages

20

Pages from-to

2781-2797

UT code for WoS article

000455586500026

EID of the result in the Scopus database

2-s2.0-85057047981