Skip to main content

Part of the book series: Ettore Majorana International Science Series ((EMISS,volume 38))

  • 867 Accesses

Abstract

Electrons in the low-energy range of about 1 keV or less play an important role in many fields of radiation research for two reasons: firstly, they are created in large numbers during the passage of all kinds of ionizing radiation through matter, and secondly, they have a linear energy transfer comparable to that of low-energy protons and a-particles, and accordingly they are responsible for the greater part of radiation damage observable in any material. A detailed understanding of the action of low-energy electrons in matter therefore is required in many contexts. In the fields of dosimetry, for example, the determination of the absorbed dose in water or the air kerma is great practical importance, but in most experiments only the amount of ionization produced by secondary electrons within the sensitive volume of a dosimeter can be measured. The results of ionization measurements therefore must converted to quantities based on energy absorption or energy transfer, either by calibration or numerically using an appropriate conversion factor. The most frequently used conversion factor is the so-called W-value, which is the mean energy required to produce an ion pair upon complete slowing down of a charged particle. Its relation to the primary particle kinetic energy T, and to the mean n umber N i of ionizations produced (ionization yield), is given by

$$W(T) = \frac{T}{{{{N}_{i}}(T)}}.$$
(15.1)

This is a preview of subscription content, log in via an institution to check access.

Access this chapter

Chapter
USD 29.95
Price excludes VAT (USA)
  • Available as PDF
  • Read on any device
  • Instant download
  • Own it forever
eBook
USD 119.00
Price excludes VAT (USA)
  • Available as PDF
  • Read on any device
  • Instant download
  • Own it forever
Softcover Book
USD 159.99
Price excludes VAT (USA)
  • Compact, lightweight edition
  • Dispatched in 3 to 5 business days
  • Free shipping worldwide - see info

Tax calculation will be finalised at checkout

Purchases are for personal use only

Institutional subscriptions

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. M. Inokuti, “Ionization Yields in Gases under Electron Irradiation”, Radiat. Res. 64 (1976) 6.

    Article  Google Scholar 

  2. R. L. Platzman, “Energy Spectrum of Primary Activations in the Action of Ionizing Radiation”, in Radiation Research, edited by G. Silini ( North-Holland Publishing Comp., Amsterdam, 1966 ) 20.

    Google Scholar 

  3. U. Fano, “Platzman’s Analysis of the Delivery of Radiation Energy to Molecules”, Radiat. Res. 64 (1975) 217.

    Article  Google Scholar 

  4. M. Inokuti, D. A. Douthat, A. R. P. Rau, “Degradation Spectra and Ionization Yields of Electrons in Gases,” Proc. 5th Symp. on Microdosim. (1975) 977.

    Google Scholar 

  5. M. Inokuti, “Inelastic Collisions of Fast Charged Particles with Atoms and Molecules - The Bethe Theory Revisited”, Rev. Mod. Phys. 43 (1971) 297.

    Article  ADS  Google Scholar 

  6. M. Inokuti, Y. Itikawa, J. E. Turner, “Addenda: Inelastic Collisions of Fast Charged Particles with Atoms and Molecules - The Bethe Theory Revisited”, Rev. Med. Phys. 50 (1978) 23.

    Article  ADS  Google Scholar 

  7. Y.-K. Kim, “Angular Distributions of Secondary Electrons in the Dipole Approximation”, Phys. Rev. A6 (1972) 666.

    Article  ADS  Google Scholar 

  8. Y.-K. Kim, “Energy Distribution of Secondary Electrons. I. Consistency of Experimental Data”, Radiat. Res. 61 (1975) 21.

    Article  Google Scholar 

  9. Y.-K. Kim, “Energy Distribution of Secondary Electrons. II. Normalization and Extrapolation of Experimental Data”, Radiat. Res. 64 (1975) 205.

    Article  Google Scholar 

  10. Y.-K. Kim, “Energy Distribution of Secondary Electrons”, Radiat. Res. 64 (1975) 96.

    Article  Google Scholar 

  11. Y.-K. Kim, T. Noguchi, “Secondary Electrons Ejected by Protons and Electrons”, Int. J. Radiat. Phys. Chem. 7 (1975) 77.

    Article  Google Scholar 

  12. H. C. Tuckwell, Y.-K. Kim, “Effects of Partial Cross Sections on the Energy Distribution of Slow Secondary Electrons”, J. Chem. Phys. 64 (1976) 333.

    Article  ADS  Google Scholar 

  13. .D. E. Gerhart, “Comprehensive Optical and Collision Data for Radiation Action. I H2”, J. Chem. Phys. 62 (1975) 821.

    Article  ADS  Google Scholar 

  14. S. C. Soong, “Inner-Shell Contributions to Electron Degradation Spectra”, Radiat. Res. 67 (1976) 187.

    Article  Google Scholar 

  15. E. Eggarter, “Comprehensive Optical and Collision Data for Radiation Action. II Ar”, J. Chem. Phys. 62 (1975) 833.

    Article  ADS  Google Scholar 

  16. H. G. Paretzke, M. J. Berger, “Stopping Power and Energy Degradation for Electrons in Water Vapor”, Proc. 6th Symp. on Microdosim. (1978) 749.

    Google Scholar 

  17. R. N. Hamm, H. A. Wright, R. H. Ritchie, J. E. Turner, J. P. Turner, “Monte Carlo Calculation of Transport of Electrons through Liquid Water”, Proc. 5th Symp. on Microdosim. (1975) 1037.

    Google Scholar 

  18. R. H. Ritchie, R. N. Hamm, J. E. Turner, H. A. Wright, “The Interaction of Swift Electrons with Liquid Water”, Proc. 6th Symp. on Microdosim. (1978) 345.

    Google Scholar 

  19. D. K. Jain, S. P. Khare, “Ionizing Collisions of Electrons with C02, CO, H20, CH4 and NH4, J. Phys. B: Atom. Molec. Phys. 9 (1976) 1429.

    Article  ADS  Google Scholar 

  20. A. T. Jusick, C. E. Watson, L. R. Peterson, A. E. S. Green, “Electron Impact Cross Sections for Atmospheric Species. 1. Helium”, J. Geophys. Res. 72 (1967) 3943.

    Article  ADS  Google Scholar 

  21. L. R. Peterson, A. E. S. Green, “The Relation between Ionization Yields, Cross Sections and Loss Functions”, J. Phys. B (Proc. Phys. Soc.) Ser. 2, 1 (1968) 1131.

    ADS  Google Scholar 

  22. C. H. Jackman, R. H. Garvey, A. E. S. Green, “Electron Impact on Atmospheric Gases I. Updated Cross Sections”, J. Geophys. Res. 82 (1977) 5081.

    Article  ADS  Google Scholar 

  23. W. T. Miles, R. Thompson, A. E. S. Green, “Electron Impact Cross Sections and Energy Deposition in Molecular Hydrogen”, J. Appl. Phys. 43 (1972) 678.

    Article  ADS  Google Scholar 

  24. R. S. Stolarski, V. A. Dulock, C. E. Watson, A. E. S. Green, “Electron Impact Cross Sections for Atmospheric Species. 2. Molecular Nitrogen”, J. Geophys. Res. 72 (1967) 3953.

    Article  ADS  Google Scholar 

  25. L. R. Peterson, S. S. Prasad, A. E. S. Green, “Semi-empirical Electron Impact Cross Sections for Atmospheric Gases”, Can. J. Chem. 47 (1969) 1774.

    Article  Google Scholar 

  26. A. E. S. Green, R. S. Stolarski, “Analytic Models of Electron Impact Excitation Cross Sections”, J. Atmosph. Terr. Phys. 34 (1972) 1703.

    Article  ADS  Google Scholar 

  27. C. E. Watson, V. A. Dulock, R. S. Stolarski, A. E. S. Green, “Electron Impact Cross Sections for Atmospheric Species. 3. Molecular Oxygen”, J. Geophys. Res. 72 (1967) 3961.

    Article  ADS  Google Scholar 

  28. T. Sawada, D. L. Sellin, A. E. S. Green, “Electron Impact Excitation Cross Sections and Energy Degradation in CO”, J. Geophys. Res. 77 (1972) 4819.

    Article  ADS  Google Scholar 

  29. D. J. Strickland, A. E. S. Green, “Electron Impact Cross Sections for CO2”, J. Geophys. Res. 74 (1969) 6415.

    Article  ADS  Google Scholar 

  30. T. Sawada, D. J. Strickland, A. E. S. Green, “Electron Energy Deposition in C02” J. Geophys. Res. 77 (1972) 4812.

    Article  ADS  Google Scholar 

  31. J. J. Olivero, R. W. Stagat, A. E. S. Green, “Electron Deposition in Water Vapor, with Atmospheric Applications”, J. Geophys. Res. 77 (1972) 4797.

    Article  ADS  Google Scholar 

  32. G. J. Kutscher, A. E. S. Green, “A Model for Energy Deposition in Liquid Water”, Radiat. Res. 67 (1976) 408.

    Article  Google Scholar 

  33. A. E. S. Green, T. Sawada, “Ionization Cross Sections and Secondary Electron Distributions”, J. Atmos. Terr. Phys. 34 (1972) 1719.

    Article  ADS  Google Scholar 

  34. ICRU, Report 31, “Average Energy Required to Produce an Ion Pair”, International Commission on Radiation Units and Measurements, Washington D.C., (1979).

    Google Scholar 

  35. M. Terrissol, J. P. Patau, “Simulation du transport d’électrons d’énergie inférieure a un keV par une méthode de Monte-Carlo”, Proc. 4th Symp. on Microdosim. (1973) 717.

    Google Scholar 

  36. R. H. Garvey, A. E. S. Green, “Energy-Apportionment Techniques Based upon Detailed Atomic Cross Sections”, Phys. Rev. A14 (1976) 946.

    Article  ADS  Google Scholar 

  37. B. Grosswendt, “Determination of Statistical Fluctuations in the Ionization Yield of Low Energetic Electrons in Hydrogen”, Nucl. Instr. Meth. 198 (1982) 403.

    Article  Google Scholar 

  38. M. Terrissol, J. Fourmenty, J. P. Patau, “Détermination théorique des fonctions microdosimétriqes pour des électrons de basse énergie dans les gaz”, Proc. 5th Symp. on Microdos. (1975) 393.

    Google Scholar 

  39. B. Grosswendt, “Statistical Fluctuations of the Ionization Yield of Low-energy Electrons in He, Ne and Ar”, J. Phys. B: Atom. Mol. Phys. 17 (1984) 1391.

    Article  ADS  Google Scholar 

  40. K. Unnikrishnan, M. A. Prasad, “Energy Deposition by Electrons in Argon”, Radiat. Res. 80 (1979) 225.

    Article  Google Scholar 

  41. M. Parikh, “Energetic Electron Degradation Spectra and Initial Yields in Argon”, J. Chem. Phys. 73 (1980) 93.

    Article  ADS  Google Scholar 

  42. Dayashankar, M. A. Prasad, K. Unnikrishnan, “Energy Degradation of Electrons in Krypton”, Phys. Lett. 90A (1982) 402.

    Article  ADS  Google Scholar 

  43. Dayashankar, K. Unnikrishnan, “Ionization-Yield Fluctuations in Xenon Due to Energy Degradation of Electrons”, Phys. Lett. 99A (1983) 81.

    Article  ADS  Google Scholar 

  44. J. E. Turner, H. G. Paretzke, R. N. Hamm, H. A. Wright, R. H. Ritchie, “Comparative Study of Electron Energy Deposition and Yields in Water in the Liquid and Vapor Phases”, Radiat. Res. 92 (1982) 47.

    Article  Google Scholar 

  45. H. G. Paretzke, J. E. Turner, R. N. Hamm, H. A. Wright, R. H. Ritchie, “Calculated Yields and Fluctuations for Electron Degradation in Liquid Water and Water Vapor”, J. Chem. Phys. 84 (1986) 3182.

    Article  ADS  Google Scholar 

  46. B. Grosswendt, E. Waibel, “Transport of Low Energy Electrons in Nitrogen and Air”, Nucl. Instr. Meth. 155 (1978) 145.

    Article  Google Scholar 

  47. E. Waibel, B. Grosswendt, “Spatial Energy Dissipation Profiles, W values, Backscatter Coefficients, and Ranges for Low-Energy Electrons in Methane”, Nucl. Instr. Meth. 211 (1983) 487.

    Article  Google Scholar 

  48. B. Grosswendt, “Degradation Spectra and Statistical Ionization Yield Fluctuations for Low-Energy Electrons in TE Gas”, Proc. 8th Symp. on Microdosim. (1982) 165.

    Google Scholar 

  49. D. Combecher, “Measurement of W values of Low-Energy Electrons in Several Gases”, Radiat. Res. 84 (1980) 189.

    Article  Google Scholar 

  50. E. Eggarter, “Theory of Initial Yields of Ions Generated by Electrons in Binary Mixtures”, J. Chem. Phys. 84 (1986) 6123.

    Article  ADS  Google Scholar 

  51. A. R. P. Rau, M. Inokuti, D. A. Douthat, “Variational Treatment of Electron Degradation and Yields of Initial Molecular Species”, Phys. Rev. A18 (1978) 971.

    Article  ADS  Google Scholar 

  52. M. Inokuti, D. A. Douthat, A. R. P. Rau, “Statistical Fluctuations in the Ionization Yield and Their Relation to the Electron Degradation Spectrum”, Phys. Rev. A22 (1980) 445.

    Article  ADS  Google Scholar 

  53. B. Grosswendt, E. Waibel, “Statistical Ionization Yield Fluctuations and Determination of Spatial Ionization and Energy Absorption for Low Energy Electrons”, Radiat. Prot. Dosim. 13 (1985) 95.

    Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Editor information

Editors and Affiliations

Rights and permissions

Reprints and permissions

Copyright information

© 1988 Plenum Press, New York

About this chapter

Cite this chapter

Grosswendt, B. (1988). Low-Energy Monte Carlo and W-Values. In: Jenkins, T.M., Nelson, W.R., Rindi, A. (eds) Monte Carlo Transport of Electrons and Photons. Ettore Majorana International Science Series, vol 38. Springer, Boston, MA. https://doi.org/10.1007/978-1-4613-1059-4_15

Download citation

  • DOI: https://doi.org/10.1007/978-1-4613-1059-4_15

  • Publisher Name: Springer, Boston, MA

  • Print ISBN: 978-1-4612-8314-0

  • Online ISBN: 978-1-4613-1059-4

  • eBook Packages: Springer Book Archive

Publish with us

Policies and ethics