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T. Kib è di , B.Q. Lee, A.E. Stuchbery , K.A. Robinson (ANU) F.G. Kondev (ANL)

Atomic radiations in nuclear decay Development of a new code to incorporate atomic data into ENSDF . T. Kib è di , B.Q. Lee, A.E. Stuchbery , K.A. Robinson (ANU) F.G. Kondev (ANL). Tibor Kibèdi, Dep. of Nuclear Physics, Australian National University.

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T. Kib è di , B.Q. Lee, A.E. Stuchbery , K.A. Robinson (ANU) F.G. Kondev (ANL)

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  1. Atomic radiations in nuclear decayDevelopment of a new code to incorporate atomic data into ENSDF T. Kibèdi, B.Q. Lee, A.E. Stuchbery, K.A. Robinson (ANU) F.G. Kondev (ANL) Tibor Kibèdi, Dep. of Nuclear Physics, Australian National University 20th NSDD, Kuwait, 27 – 31 January 2013

  2. Outline • Motivation • 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 • Background • KálmánRobertson (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” • Comp. Math. Meth. in Medicine, v2012, Article ID 651475, doi:10.1155/2012/651475 • 2011 NSDD meeting (IAEA) Tibor Kibèdi, Dep. of Nuclear Physics, Australian National University 20th NSDD, Kuwait, 27 – 31 January 2013

  3. Medical applications - Auger electrons 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.” Claudius Regaud (1870-1940) Antoine Lacassagne (1884-1971) Tibor Kibèdi, Dep. of Nuclear Physics, Australian National University 20th NSDD, Kuwait, 27 – 31 January 2013

  4. Medical applications - Auger electrons 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.” Targeted tumor therapy Claudius Regaud (1870-1940) Antoine Lacassagne (1884-1971) (Courtesy of Thomas Tunningley, ANU). Tibor Kibèdi, Dep. of Nuclear Physics, Australian National University 20th NSDD, Kuwait, 27 – 31 January 2013

  5. Medical applications - Auger electrons 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.” Targeted tumor therapy • Biological effect: • Linear energy transfer LET, keV/mm electrons Kassis, Int. J. of Rad. Biol, 80 (2004) 789 (Courtesy of Thomas Tunningley, ANU). Tibor Kibèdi, Dep. of Nuclear Physics, Australian National University 20th NSDD, Kuwait, 27 – 31 January 2013

  6. Medical applications - Auger electrons 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.” Targeted tumor therapy • 2011 August, INDC International Nuclear Data Committee • Technical Meeting on Intermediate-term Nuclear Data Needs for Medical Applications: Cross Sections and Decay Data • Ed. by A.L. Nichols, et al., NDC(NDS)-0596 Auger emitters: 67Ga , 71Ge, 77Br,99mTc, 103Pd, 111In, 123I, 125I, 140Nd, 178Ta, 193Pt, 195mPt, 197Hg (Courtesy of Thomas Tunningley, ANU). Tibor Kibèdi, Dep. of Nuclear Physics, Australian National University 20th NSDD, Kuwait, 27 – 31 January 2013

  7. Atomic radiations - Basic concept X-ray emission 3D 3P M4 M5 M1 M2 M3 3S 2P L1 L2 L3 2S X-ray photon Initial vacancy 1S K Ka2 X-ray 1 secondary vacancy Tibor Kibèdi, Dep. of Nuclear Physics, Australian National University 20th NSDD, Kuwait, 27 – 31 January 2013

  8. Atomic radiations - Basic concept X-ray emission Auger-electron 3D 3P M1 M5 M4 M3 M2 M2 M3 M4 M5 M1 3S Auger-electron 2P L1 L2 L3 L3 L2 L1 2S X-ray photon Initial vacancy Initial vacancy 1S K K K L2 L3 Auger-electron 2 new secondary vacancies Ka2 X-ray 1 secondary vacancy Tibor Kibèdi, Dep. of Nuclear Physics, Australian National University 20th NSDD, Kuwait, 27 – 31 January 2013

  9. Atomic radiations - Basic concept X-ray emission Coster-Kronig electron 3D 3P CK- electron M5 M4 M3 M2 M3 M2 M1 M4 M5 M1 3S 2P L1 L2 L3 L3 L2 L1 2S Initial vacancy X-ray photon Initial vacancy 1S K K L1 L2 M1 Coster-Kronig transition 2 new secondary vacancies Ka2 X-ray 1 secondary vacancy Tibor Kibèdi, Dep. of Nuclear Physics, Australian National University 20th NSDD, Kuwait, 27 – 31 January 2013

  10. Atomic relaxation and vacancy transfer Vacancy cascade in Xe O1,2,3 • Full relaxation of an initial inner shell • vacancy creates vacancy cascade involving X-ray (Radiative) and Auger as well as Coster-Kronig (Non-Radiative) transitions • Many possible cascades for a single • initial vacancy • Typical relaxation time ~10-15 seconds • Many vacancy cascades following a • single ionisation event! A A A A A A A A N4,5 N2,3 KC N1 A A A M4,5 M3 M2 M1 A A L3 L2 L1 X Initial vacancy K M.O. Krause, J. Phys. Colloques, 32 (1971) C4-67 Tibor Kibèdi, Dep. of Nuclear Physics, Australian National University 20th NSDD, Kuwait, 27 – 31 January 2013

  11. Atomic radiations - Basic concept Vacancy cascade in Xe O1,2,3 • Vacancies on the inner-shell can be produced by • electron impact • photo ionization • ion-atom collision • internal conversion • electron capture • secondary processes accompanying • b-decay or electron capture A A A A A A A A N4,5 N2,3 KC N1 A A A M4,5 M3 M2 M1 A A L3 L2 L1 X K M.O. Krause, J. Phys. Colloques, 32 (1971) C4-67 Tibor Kibèdi, Dep. of Nuclear Physics, Australian National University 20th NSDD, Kuwait, 27 – 31 January 2013

  12. Motivation • X-ray and Auger electron spectrum is an integral part of the radiations emitted in nuclear decay • Atomic radiations are important for applications of radioisotopes (medical physics, nuclear astrophysics, nuclear engineering) • ENSDF: atomic radiations are not included Tibor Kibèdi, Dep. of Nuclear Physics, Australian National University 20th NSDD, Kuwait, 27 – 31 January 2013

  13. Atomic transition energies and rates • Basic formulas • For a single initial vacancy on the K-shell following nuclear decay Internal conversion Number of primary vacancies Electron capture X-ray emission Auger-electron in an ion Energy Intensity for L1 shell Tibor Kibèdi, Dep. of Nuclear Physics, Australian National University 20th NSDD, Kuwait, 27 – 31 January 2013

  14. Existing calculations • Physical approach Tibor Kibèdi, Dep. of Nuclear Physics, Australian National University 20th NSDD, Kuwait, 27 – 31 January 2013

  15. Existing calculations • Auger electron yield per nuclear decay Tibor Kibèdi, Dep. of Nuclear Physics, Australian National University 20th NSDD, Kuwait, 27 – 31 January 2013

  16. 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 Tibor Kibèdi, Dep. of Nuclear Physics, Australian National University 20th NSDD, Kuwait, 27 – 31 January 2013

  17. 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 coefficients (ICC):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: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 Tibor Kibèdi, Dep. of Nuclear Physics, Australian National University 20th NSDD, Kuwait, 27 – 31 January 2013

  18. BrIccEmis • Reads the ENSDF file, evaluates absolute decay intensities of EC, GAMMA, CE and PAIR transitions • Simulates a large number events: 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! • (55Fe: 15 k, 201Tl: 1300k) • Emitted atomic radiations stored on disk (~Gb files) • Separate files for X-rays and Auger electrons • Smaller programs to sort/project energy spectra, produce detailed reports Tibor Kibèdi, Dep. of Nuclear Physics, Australian National University 20th NSDD, Kuwait, 27 – 31 January 2013

  19. 111In EC – vacancy propagation Tibor Kibèdi, Dep. of Nuclear Physics, Australian National University 20th NSDD, Kuwait, 27 – 31 January 2013

  20. 99mTc atomic radiations below L-shell BE Tibor Kibèdi, Dep. of Nuclear Physics, Australian National University 20th NSDD, Kuwait, 27 – 31 January 2013

  21. 99mTc atomic radiations – X-rays Tibor Kibèdi, Dep. of Nuclear Physics, Australian National University 20th NSDD, Kuwait, 27 – 31 January 2013

  22. 99mTc Auger electrons • BrIccEmis: • 10 M simulated decay events • 455 type of Auger transitions • 1981Ge05: measured Auger electrons in 1500-2300 eV only Low energy Auger electrons • B.Q. Lee, Honours Thesis, ANU 2012 • 2012Le09 Lee et al., Comp. Math. Meth. in Medicine, v2012, Art. ID 651475 Tibor Kibèdi, Dep. of Nuclear Physics, Australian National University 20th NSDD, Kuwait, 27 – 31 January 2013

  23. 99mTc atomic radiations – Auger electrons Tibor Kibèdi, Dep. of Nuclear Physics, Australian National University 20th NSDD, Kuwait, 27 – 31 January 2013

  24. 99mTc atomic radiations – Auger electrons ~95% below 500 eV Tibor Kibèdi, Dep. of Nuclear Physics, Australian National University 20th NSDD, Kuwait, 27 – 31 January 2013

  25. 131mXe IT – charge state at the end of atomic relaxation • Only a handful of measurements exist for ionization by nuclear decay • 131mXe: F. Pleasonton, A.H. Snell, Proc. Royal Soc. (London) 241 (1957) 141 • 37Ar: 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 ~0.7-1.0 charge Tibor Kibèdi, Dep. of Nuclear Physics, Australian National University 20th NSDD, Kuwait, 27 – 31 January 2013

  26. 111In – 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 Tibor Kibèdi, Dep. of Nuclear Physics, Australian National University 20th NSDD, Kuwait, 27 – 31 January 2013

  27. 111In – 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 • KL2L3(1D2) energy (eV): • Multiplet splitting could not be reproduced in JJ coupling scheme • Similar discrepancies have been seen in other elements (Z=47, Kawakami, Phys. LettA121 (1987) 414) DE≈60 eV! Tibor Kibèdi, Dep. of Nuclear Physics, Australian National University 20th NSDD, Kuwait, 27 – 31 January 2013

  28. Breit and other QED contributions (2002Ga47) Alternative solution: Semi empirical corrections, like Larkins (1977La19) or Carlson (1977Ca31) used Z=49 (In) ~60 eV Gaston et al. Phys. Rev A66(2002) 062505 Tibor Kibèdi, Dep. of Nuclear Physics, Australian National University 20th NSDD, Kuwait, 27 – 31 January 2013

  29. Summary – Program developments • 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: 55Fe 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 55Fe EC) Tibor Kibèdi, Dep. of Nuclear Physics, Australian National University 20th NSDD, Kuwait, 27 – 31 January 2013

  30. Inclusion of atomic relaxation data into ENSDF Tibor Kibèdi, Dep. of Nuclear Physics, Australian National University 20th NSDD, Kuwait, 27 – 31 January 2013

  31. Inclusion of atomic relaxation data into ENSDF X-rays Auger electrons Before daughter GS level record • Intensity need to be normalised to GAMMA-rays; same normalisation is valid for both • Number of entries on the “R” (RELAXATION) records can automatically generated according to Z • Detailed spectra (list or figure) of the X-rays and Auger electrons can be generated and distributed for the user Tibor Kibèdi, Dep. of Nuclear Physics, Australian National University 20th NSDD, Kuwait, 27 – 31 January 2013

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