Basunia, M. Shamsuzzoha

University of Saskatchewan's Research Archive

Status and inspection of isotopic decay data for normalizationM. Shamsuzzoha Basunia11th ICI Conference, Saskatoon, Canada, July 23-27, 20232Outline:  Motivation Decay data• Table of Radioactive Isotopes, ENSDF, DDEP, etc. Recent work Research opportunities Decay data dissemination/retrieval Summary3Motivation  Accurate and precise isotopic decay (α, β, γ, etc.) data are important for applied and basic sciences. Decay data normalization• Provides radiation emission probabilities Several methods have been used to normalize the decay scheme• Measured emission probability Pγ, Pβ-, Pβ+, or I511, Ix-ray• Also from a complete γ-decay scheme (g.s. β-feeding is known)  Parent, daughter properties Level energy, spin and parity (Jπ), half-life (t1/2), etc. α, β, γ, γ-multipolarity, mixing ratio (δ), conversion coefficient (α),  etc.It is important to check the normalization by more than one method4Decay data • Table of Radioactive Isotopes (1986) – a product of LBNL compilation of nuclear data since 1940s - initiated by Prof. Glenn Seaborg• Nuclear Data Sheets/ENSDF - similar effort since mid 1940’s at Clinton Lab/ORNL by Prof. Katherine Way  (Nuclear Data Sheets since 1966)• Currently more than 3,200 experimental decay data sets available in the Evaluated Nuclear Structure Data File (ENSDF)• Decay Data Evaluation Project (DDEP) –at LNHB, France - since mid 1995s5Recent work (1): 86gY (t1/2=14.7 h) (β+)Q+=5240 (14) keV(partial)Levels: 32Gammas: 104Beta group: 29 and %β+ = 32 (2)Total E(cal) = 5255 (60) keVMissing γ rays often yield inaccurateIβ feeding for levelstheranostic pair of 90Y (= 2.7 d) (β-) Data need: accurate %β+6Recent work (2): 86gYForschungszentrum Jülich, Jülich, Germany7Equations and features: Several methods have been used to normalize the decay scheme• 511 (annihilation) and x-ray measurements – provide opportunities for independent check• For cases: %β+ + %ε (EC) = 100           	 	   From known %Iγ (dependent)From 100 (independent)A0(activity), CPS(count/s),ε(detector efficiency),Iγ (emission probability), Pk(capture from k-shell),FY(fluorescence yield) 8Results: 86gY• From two samples:Using %Iγ (1076.6) Using %Iγ (443.1) For 10072.4 73.5 72.071.7 73.3 72.9• Average (of 2 values for 100) =  72.5• Average (of 4 values using %Iγ) = 72.7Consistency between  independent and dependent approaches%β+ = 27.1 ± 1.9 and %ε = 72.6 ± 5.2• Uncertainty: Propagated uncertainties of peak area, in-flight annihilation, detector efficiency, x-ray attenuation, fluorescence yield, electron capture from k-shell, etc. 9Research opportunities:For radioisotopes: %β+ + %ε = 100 Total %β+ by 511 (annihilation) and x-ray measurements provides independent data   511 and x-ray measurements – provide opportunities for checking %Iγ or confirming any assumptions, if used  More than 3,200 decay datasets in the ENSDF• About 2,400 represent β- and β++EC decay, about 1920 are normalized• We checked a group of applied isotopes to benefit from 511 and x-ray measurements3426 in the ENSDFFirst step for further studies 10Example: 72As (t1/2 = 26 h) (β+) theranostic pair of 77As (t1/2 = 38.8 h) (β-) Q+ = 4356 (4) keV(partial)Levels: 33Gammas: 85Beta group: 32 and %β+ = 88 (2)Total E(cal) = 4358 (56) keV%Iγ(834)=82 (2)Other method: Σ total transition to g.s. would yield:%Iγ(834)=79.5 (19)In general %Iγ is less affected compared to total %β+11Decay data dissemination/retrieval: Sometimes published results take time to get to the ENSDF database and would miss in retrieval through web applications (like NuDAT and LiveChart) 2015Ch572021Bl04 - Appl.Radiat.Isot. 170, 109625 (2021)2020Ba30 - Phys.Rev. C 101, 064619Check literature, the XUNDL database at nndc.bnl.gov or contact database manager or nuclear structure data evaluatorSummary:12 Accurate and precise isotopic decay data are important for applied and basic sciences We have determined %β+ (86Y(14.7 h)) = 27.2 ± 2.0 by measuring 511-keV annihilation radiation and x-rays. Excellent agreement with the value (27.9 ± 1.2) deduced using the latest decay scheme (2020Gu18) Several methods have been used to normalize the decay scheme• 511 (annihilation) and x-ray measurements – provide opportunities for independent check for cases: %β+ + %ε = 100• We plan to continue measurements with 511 and x-rays For the latest decay data – please check the literature, the XUNDL database or contact the ENSDF database manager or any nuclear structure evaluators13 Forschungszentrum Jülich, GermanySyed M. QaimBernhard ScholtenIngo Spahn and Bernd Neumaier Lawrence Berkeley National Laboratory, USAM. Shasmuzzoha BasuniaLee A. BernsteinAaron M. Hurst and Andrew S. Voyles Bangladesh Atomic Energy Commission, BangladeshMd. Shuza Uddin Collaborators:Thank you for your attention14Acknowledgements:The research at LBNL was supported by the U.S. Department of Energy Isotope Program, managed by the Office of Science for Isotope R&D and Production, carried out under Lawrence Berkeley National Laboratory (Contract No. DE-AC02-05CH11231)15Back-up slides16Retrieval using NuDat:17Retrieval using NuDat:

Status and inspection of isotopic decay data for normalization

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Status and inspection of isotopic decay data for normalization

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