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Calculation of atomic radiations in nuclear decay – BrIccEmis and beyond T. Kibèdi, B.Q. Lee, A.E. Stuchbery, K.A. Robinson Tibor Kibèdi, Dep. of Nuclear.

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Presentation on theme: "Calculation of atomic radiations in nuclear decay – BrIccEmis and beyond T. Kibèdi, B.Q. Lee, A.E. Stuchbery, K.A. Robinson Tibor Kibèdi, Dep. of Nuclear."— Presentation transcript:

1 Calculation of atomic radiations in nuclear decay – BrIccEmis and beyond T. Kibèdi, B.Q. Lee, A.E. Stuchbery, K.A. Robinson Tibor Kibèdi, Dep. of Nuclear Physics, Australian National UniversityDDEP Workshop, Paris, 8-10 October 2012

2 Tibor Kibèdi, Dep. of Nuclear Physics, Australian National UniversityDDEP Workshop, Paris, 8-10 October 2012 Outline Talk is largely based on K lmn Robertson (ANU) Honours project (2010) Boon Quan Lee (ANU) Honours project (2012) 2012Le09 Lee et al., “Atomic Radiations in the Decay of Medical Radioisotopes: A Physics Perspective” Computational and Mathematical Methods in Medicine Volume 2012, Article ID , doi: /2012/ NSDD meeting (IAEA)  Radiative and Non-radiative atomic transitions in nuclear decay  Nuclear and atomic data  Existing programs to evaluate atomic radiations  New model based on Monte Carlo approach  Future directions

3 Tibor Kibèdi, Dep. of Nuclear Physics, Australian National UniversityDDEP Workshop, Paris, 8-10 October 2012 Atomic radiations - Basic concept 1S 2S 2P 3S 3P 3D K L1L1 L2L2 L3L3 M1M1 M2M2 M3M3 M4M4 M5M5 Initial vacancy Vacancies on the inner-shell can be produced by  electron impact  photo ionization  ion-atom collision  internal conversion  electron capture  secondary processes accompanying  -decay or electron capture

4 Tibor Kibèdi, Dep. of Nuclear Physics, Australian National UniversityDDEP Workshop, Paris, 8-10 October 2012 Atomic radiations - Basic concept 1S 2S 2P 3S 3P 3D K L1L1 L2L2 L3L3 M1M1 M2M2 M3M3 M4M4 M5M5 Initial vacancy X-ray emission X-ray photon K  2 X-ray 1 secondary vacancy

5 Tibor Kibèdi, Dep. of Nuclear Physics, Australian National UniversityDDEP Workshop, Paris, 8-10 October 2012 Atomic radiations - Basic concept K L1L1 L2L2 L3L3 M1M1 M2M2 M3M3 M4M4 M5M5 Initial vacancy 1S 2S 2P 3S 3P 3D K L1L1 L2L2 L3L3 M1M1 M2M2 M3M3 M4M4 M5M5 Initial vacancy X-ray emission K  2 X-ray 1 secondary vacancy X-ray photon

6 Tibor Kibèdi, Dep. of Nuclear Physics, Australian National UniversityDDEP Workshop, Paris, 8-10 October 2012 Atomic radiations - Basic concept K L1L1 L2L2 L3L3 M1M1 M2M2 M3M3 M4M4 M5M5 Auger-electron K L2 L3 Auger-electron 2 new secondary vacancies 1S 2S 2P 3S 3P 3D K L1L1 L2L2 L3L3 M1M1 M2M2 M3M3 M4M4 M5M5 Initial vacancy X-ray emission X-ray photon Initial vacancy K  2 X-ray 1 secondary vacancy

7 Tibor Kibèdi, Dep. of Nuclear Physics, Australian National UniversityDDEP Workshop, Paris, 8-10 October 2012 Atomic radiations - Basic concept K L1L1 L2L2 L3L3 M1M1 M2M2 M3M3 M4M4 M5M5 Coster-Kronig electron CK- electron L1 L2 M1 Coster-Kronig transition 2 new secondary vacancies 1S 2S 2P 3S 3P 3D K L1L1 L2L2 L3L3 M1M1 M2M2 M3M3 M4M4 M5M5 Initial vacancy X-ray emission X-ray photon Initial vacancy K  2 X-ray 1 secondary vacancy

8 Tibor Kibèdi, Dep. of Nuclear Physics, Australian National UniversityDDEP Workshop, Paris, 8-10 October 2012 Atomic relaxation and vacancy transfer K L1L1 L2L2 L3L3 M1M1 M2M2 M3M3 M 4,5 N1N1 N 2,3 N 4,5 O 1,2,3 A vacancy cascade in Xe From M.O. Krause, J. Phys. Colloques, 32 (1971) C4-67 X A A A A A KC A A A A A A A A  Full relaxation of an initial inner shell vacancy creates vacancy cascade involving X -ray (Radiative) and A uger as well as C oster- K ronig (Non-Radiative) transitions  Many possible cascades for a single initial vacancy  Typical relaxation time ~ seconds  Many vacancy cascades following a single ionisation event! Initial vacancy

9 Tibor Kibèdi, Dep. of Nuclear Physics, Australian National UniversityDDEP Workshop, Paris, 8-10 October 2012 Transition energies and Rates Auger-electronX-ray emission Number of primary vacancies For a single initial vacancy on the K-shell following nuclear decay Internal conversion Electron capture Energy Intensity for L1 shell in an ion

10 Tibor Kibèdi, Dep. of Nuclear Physics, Australian National UniversityDDEP Workshop, Paris, 8-10 October 2012 Medical applications - Auger electrons Kassis, Int. J. of Radiation Biology, 80 (2004) 789 electrons Biological effect: Linear energy transfer LET, keV/  m

11 Tibor Kibèdi, Dep. of Nuclear Physics, Australian National UniversityDDEP Workshop, Paris, 8-10 October 2012 Medical applications - Auger electrons 2011 August, INDC International Nuclear Data Committee Technical Meeting on Intermediate-term Nuclear Data Needs for Medical Applications: Cross Sections and Decay Data Edited by A.L. Nichols, et al., NDC(NDS)-0596 (Courtesy of Thomas Tunningley, ANU). Auger emitters: 67 Ga, 71 Ge, 77 Br, 99m Tc, 103 Pd, 111 In, 123 I, 125 I, 140 Nd, 178 Ta, 193 Pt, 195m Pt, 197 Hg Targeted tumor therapy Regaud and Lacassagne (1927) “The ideal agent for cancer therapy would consist of heavy elements capable of emitting radiations of molecular dimensions, which could be administered to the organism and selectively fixed in the protoplasm of cells one seeks to destroy.” Regaud and Lacassagne (1927) “The ideal agent for cancer therapy would consist of heavy elements capable of emitting radiations of molecular dimensions, which could be administered to the organism and selectively fixed in the protoplasm of cells one seeks to destroy.”

12 Tibor Kibèdi, Dep. of Nuclear Physics, Australian National UniversityDDEP Workshop, Paris, 8-10 October 2012 Existing calculations Physical approach RADARDDEPEckerman & Endo (2007) Howell (1992) Stepanek (2000) Pomplun (2012) Nuclear decay data ENSDFDDEPENSDF ICRP38 Conversion coefficients HsIccRpIcc/BrIccRpIcc, 1978 Band RpIcc2000 StepanekHsIcc, 1971 Dragoun, 1976 Band Electron Capture Ratios 1971 Gove & Martin 1995 Schönfeld1977 Bambynek1971 Gove & Martin, 1970Martin 1971 Gove & Martin, 1970Martin 1971 Gove & Martin Atomic transition rates 1972 Bambynek, RADLST 1974 Scofield, 1995 Schönfeld & Janßen, 2006 Be et al., EMISSION 1991 Perkins, EDISTR Chen, 1972/1975 McGuire, 1983 Kassis, 1974 Scofield, 1974 Manson & Kenedy 1991 Perkins1979 Chen, 1972/1975 McGuire, 1970 Storm & Israel, 1979 Krause Atomic transition energies 1970 Bearden & Burr, Neutral atom 1977 Larkins, Semi-empirical 1991 Perkins, Neutral atom Z/Z+1 (Auger), Neutral atom (X- ray) Dirack-Fock calculation 1991 Desclaux, Dirack-Fock calculation Vacancy propagation Deterministic (+++) Monte Carlo with charge neutralization Monte Carlo

13 Tibor Kibèdi, Dep. of Nuclear Physics, Australian National UniversityDDEP Workshop, Paris, 8-10 October 2012 Existing calculations Auger electron yield per nuclear decay RADARDDEPEckerman & Endo (2007) Howell (1992) Stepanek (2000) Pomplun (2012) 99m Tc (6.007 h) In (2.805 d) I (13.22 h) I (59.4 d) Tl (3.04 d) Vacancy propagation Deterministic (+++) Monte Carlo with charge neutralization Monte Carlo

14 Tibor Kibèdi, Dep. of Nuclear Physics, Australian National UniversityDDEP Workshop, Paris, 8-10 October 2012 Existing programs Common problems / limitations  In some cases neutral atom binding energies are used for atoms with vacancies; i.e. for ions  Single initial vacancy is considered. Secondary vacancies are ignored  Atomic radiations only from primary vacancies on the K and L shell  Limited information on sub-shell rates  Auger electrons below ~1 keV are often omitted

15 Tibor Kibèdi, Dep. of Nuclear Physics, Australian National UniversityDDEP Workshop, Paris, 8-10 October 2012 BrIccEmis – Monte Carlo approach for vacancy creation and propagation  Initial state: neutral isolated atom  Nuclear structure data from ENSDF  Electron capture (EC) rates: Schönfeld (1998Sc28)  Internal conversion (IC) coefficients: BrIcc (2008Ki07)  Auger and X-ray transition rates: EADL (1991 Perkins) Calculated for single vacancies!  Auger and X-ray transition energies: RAINE (2002Ba85) Calculated for actual electronic configuration!  Vacancy creation and relaxation from EC and IC are treated independently  Ab initio treatment of the vacancy propagation:  Transition energies and rates evaluated on the spot  Propagation terminated once the vacancy reached the valence shell

16 Tibor Kibèdi, Dep. of Nuclear Physics, Australian National UniversityDDEP Workshop, Paris, 8-10 October 2012 BrIccEmis  Reads the ENSDF file, evaluates absolute decay intensities of EC, GAMMA, CE and PAIR transitions  Simulates a number (100k-10M) radioactive decays followed by atomic relaxation  Electron configurations and binding energies stored in memory (and saved on disk). New configurations only calculated if needed. ( 55 Fe: 15 k, 201 Tl: 1300k)  Emitted atomic radiations together with shells involved stored like histories in large files (several Gb)  Separate files for X-rays and Auger electrons  Smaller programs to sort/project energy spectra, produce detailed reports

17 Tibor Kibèdi, Dep. of Nuclear Physics, Australian National UniversityDDEP Workshop, Paris, 8-10 October In EC – vacancy propagation

18 Tibor Kibèdi, Dep. of Nuclear Physics, Australian National UniversityDDEP Workshop, Paris, 8-10 October m Tc atomic radiations keV below L-shell BE

19 Tibor Kibèdi, Dep. of Nuclear Physics, Australian National UniversityDDEP Workshop, Paris, 8-10 October m Tc atomic radiations – X-rays DDEPBrIccEmis K1K E E-2 K2K E E-2 KK E E-2 L[2.134:3.002] 4.82E E-3 M E-4 N E-1

20 Tibor Kibèdi, Dep. of Nuclear Physics, Australian National UniversityDDEP Workshop, Paris, 8-10 October m Tc atomic radiations – Auger electrons DDEPBrIccEmis KLL[14.86:15.58] 1.49E E-2 KLX[17.43:18.33] 2.79E E-3 KXY[19.93:21.00] 2.8E E-4 K-total 2.15E E-2 CK LLM2.08E CK LLX E-3 LMM E-2 LMX E-2 LXY E-4 L-total[1.6:2.9] 1.089E E-1

21 Tibor Kibèdi, Dep. of Nuclear Physics, Australian National UniversityDDEP Workshop, Paris, 8-10 October m Tc atomic radiations – Auger electrons DDEPBrIccEmis CK MMX E-1 MXY E+0 Super CK NNN E-1 CK NNX E-1 Total yield Auger electron per nuclear decay

22 Tibor Kibèdi, Dep. of Nuclear Physics, Australian National UniversityDDEP Workshop, Paris, 8-10 October 2012 BrIccEmis: spectrum from 10 M simulated decay events 99m Tc Auger electrons No experimental spectrum to compare with

23 Tibor Kibèdi, Dep. of Nuclear Physics, Australian National UniversityDDEP Workshop, Paris, 8-10 October In – experiment vs calculation E.A. Yakushev, et al., Applied Radiation and Isotopes 62 (2005) 451 ESCA; FWHM = 4 eV Calculations normalized to the strongest experimental line

24 Tibor Kibèdi, Dep. of Nuclear Physics, Australian National UniversityDDEP Workshop, Paris, 8-10 October In – experiment vs calculation A. Kovalik, et al., J. of Electron Spect. and Rel. Phen. 105 (1999) 219 ESCA; FWHM = 7 eV Calculated energies are higher KL 2 L 3 ( 1 D 2 ) energy (eV): Multiplet splitting could not be reproduced in JJ coupling scheme Similar discrepancies have been seen in other elements (Z=47, Kawakami, Phys. Lett A121 (1987) 414) (14)Experiment Kovalik (1999) Semi-empirical Larkins (1979La19) 19381RAINE (2002Ba85)

25 Tibor Kibèdi, Dep. of Nuclear Physics, Australian National UniversityDDEP Workshop, Paris, 8-10 October 2012 K-shell binding energies for superheavy elements (2012Ki04) 2002Ga47 & 2008Th05: Breit magnetic electron interaction and the quantum electrodynamical (QED) corrections.

26 Tibor Kibèdi, Dep. of Nuclear Physics, Australian National UniversityDDEP Workshop, Paris, 8-10 October 2012 Breit and other QED contributions (2002Ga47) Z=49 (In) ~60 eV Alternative solution: Semi empirical corrections, like Larkins (1977La19) or Carlson (1977Ca31) used Alternative solution: Semi empirical corrections, like Larkins (1977La19) or Carlson (1977Ca31) used

27 Tibor Kibèdi, Dep. of Nuclear Physics, Australian National UniversityDDEP Workshop, Paris, 8-10 October m Xe IT – charge state at the end of atomic relaxation  Only a handful of measurements exist for ionization by nuclear decay  131m Xe: F. Pleasonton, A.H. Snell, Proc. Royal Soc. (London) 241 (1957) 141  37 Ar: A.H. Snell, F. Pleasonton, Phys. Rev. 100 (1955) 1396  Good tool to asses the completeness of the vacancy propagation  BrIccEmis: mean value is lower by ~ charge

28 Tibor Kibèdi, Dep. of Nuclear Physics, Australian National UniversityDDEP Workshop, Paris, 8-10 October 2012 Summary RelaxData/BrIccRelax  BrIccEmis: calculation intensive approach (hours to days)  RelaxData (under development):  Nuclear decay event (EC or CE) produces a SINGLE INITIAL vacancy  Considering a single atomic vacancy the relaxation process independent what produced the vacancy  Compile a database of atomic radiation spectra for  produced by a single initial vacancy on an atomic shell  Carry out calculations of all elements and shells  Example: 55 Fe EC, 7 shells for Z=25 and 26, calculated in couple of hours (1 M each shell)  Replace EADL fixed rates and binding energies from RAINE with GRASP2k/RATIP calculations  BrIccRelax (under development): Evaluate primary vacancy distribution and construct atomic spectra from the data base (20 seconds for 55 Fe EC)


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