Advertisement

Quenching Correction in Liquid Scintillation Counting

  • C. T. Peng

Abstract

Two types of quenching are encountered in liquid scintillation counting, chemical and color quenching. Chemical quenching is caused by the presence of nonfluorescent molecules in the liquid scintillator system which interfere with the energy transfer between the solvent and the organic scintillator. In a scintillation solution, the radiation energy from a radioactive sample is expended in inducing molecular excitation of the solvent molecule. This excitation energy is transferred, according to Kallman and coworkers [1], by a process of diffusion, migration, or single-step jump to the solute molecule. If the solute molecules are those of an organic scintillator, they will be excited and then de-excited, with emission of photons which can be detected by a photomultiplier tube and counted. If the solute molecules are those of a nonfluorescent compound, they will be excited, but de-excitation occurs by radiationless transition without concomitant emission of photons. This thermal degradation of radiation energy without enhancing the fluorescence yield of the liquid scintillator system is the cause of chemical quenching.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    Brown, F. H., Furst, M., and Kallman, H., Dis. Faraday Soc. 27: 43 (1959).CrossRefGoogle Scholar
  2. 2.
    Herberg, R. J., Anal. Chem. 32: 43 (1960).Google Scholar
  3. 3.
    Halvorsen, K., in Tritium in the Physical and Biological Sciences, Vol. 1, International Atomic Energy Agency, Vienna, 1963, p. 313.Google Scholar
  4. 4.
    Herberg, R. J., Anal. Chem. 32: 1468 (1960).CrossRefGoogle Scholar
  5. 5.
    Ross, H.H., and Yerick, R. E., Anal. Chem. 35: 794 (1963).CrossRefGoogle Scholar
  6. 6.
    DeBersaques, J., Int. J. Appl. Rad. Isotopes 14: 173 (1963).CrossRefGoogle Scholar
  7. 7.
    Ross, H.H., Int. J. Appl. Rad. Isotopes 15: 273 (1964).CrossRefGoogle Scholar
  8. 8.
    Baillie, L.A., Int. J. Appl. Rad. Isotopes 8: 1 (1960).CrossRefGoogle Scholar
  9. 9.
    Bush, E., Anal. Chem. 35: 1024 (1963).CrossRefGoogle Scholar
  10. 10.
    Bruno, G.A., and Christian, J.E., Anal. Chem. 33: 650 (1962).CrossRefGoogle Scholar
  11. 11.
    Davidson, J.D., and Feigelson, P., Int. J. Appl. Rad. Isotopes 2: 13 (1957).CrossRefGoogle Scholar
  12. 12.
    Weltman, J. K., and Talmage, D.W., Int. J. Appl. Rad. Isotopes 14: 541 (1963).CrossRefGoogle Scholar
  13. 13.
    Takahashi, H„ Hattori, T., and Maruo, B., Anal. Chem. 35: 1982 (1963).CrossRefGoogle Scholar
  14. 14.
    Takahashi, H., Hattori, T., and Maruo, B., Anal. Biochem. 2: 447 (1961).CrossRefGoogle Scholar
  15. 15.
    Kaufman, W. J., Nir, A., Parks, G., and Hours, R. M., in Tritium in Physical and Biological Sciences, Vol. 1, International Atomic Energy Agency, Vienna, 1962,. p. 251.Google Scholar
  16. 16.
    Strominger, D., Hollander, J.M., and Seaborg, G.T., Rev. Mod. Phys. 30: 630 (1958).CrossRefGoogle Scholar
  17. 17.
    Dobbs, H.E., Nature 20: 1283 (1963).CrossRefGoogle Scholar
  18. 18.
    Fleishman, D.G., and Glazunov, V.V., Pribory i TekhnikaEksperimenta, No. 3, 55 (1962).Google Scholar
  19. 19.
    Higashimura, T., Yamada, O., Nohara, N., and Shidei, T., Int. J. Appl. Rad. Isotopes 13: 308 (1962).CrossRefGoogle Scholar
  20. 20.
    Horrocks, D.L., Rev. Sci. Instr. 35: 334 (1964).CrossRefGoogle Scholar
  21. 21.
    Horrocks, D.L., Nature 202: 78 (1964).CrossRefGoogle Scholar
  22. 22.
    Peng, C.T., in Bell, C.G. Jr., and Hayes, F.N. (editors), Liquid Scintillation Counting, Pergamon Press, London, 1958, p. 198.Google Scholar
  23. 23.
    Peng, C.T., Anal. Chem. 32: 1292 (1960).CrossRefGoogle Scholar
  24. 24.
    Toporek, M., Int. J. Appl. Rad. Isotopes 8: 229 (1960).CrossRefGoogle Scholar
  25. 25.
    Peng, C.T., Anal. Chem. 36: 2456 (1964).CrossRefGoogle Scholar
  26. 26.
    Hayes, F.N., Int. J. Appl. Rad. Isotopes 1: 46 (1956).CrossRefGoogle Scholar
  27. 27.
    Okita, G.T., Spratt, J., and LeRoy, G.G., Nucleonics 14 (No. 3): 76 (1956).Google Scholar
  28. 28.
    Peng, C.T., in Daub, G.H., Hayes, F.N., and Sullivan, E. (editors), Organic Scintillation Detectors, U.S. Government Printing Office, Washington, D.C., 1960, T1D 7612, p. 260.Google Scholar
  29. 29.
    Herberg, R. J., Anal. Chem. 35: 786 (1963).CrossRefGoogle Scholar
  30. 30.
    Packard, L. E., in Bell, C. G. Jr., and Hayes, F.N. (editors), Liquid Scintillation Counting, Pergamon Press, London, 1958, p. 50.Google Scholar
  31. 31.
    Wang, C.H., Atomlight 21:1(1962); and in Rothchild, S. (editor), Advances in Tracer Methodology, Vol. 1, Plenum Press, New York, 1962, p. 274.Google Scholar
  32. 32.
    Perin, F., Ann. Phys. 17: 283 (1932).CrossRefGoogle Scholar
  33. 33.
    Foerster, T., Fluoreszenz Organischer Verbindungen, Vandenhoeck & Ruprecht, Goettingen, 1951.Google Scholar
  34. 34.
    Stern, O., and Volmer, M., Phys. Z. 20: 183 (1919)Google Scholar
  35. 35.
    Scales, B., Anal. Biochem. 5: 489 (1963).CrossRefGoogle Scholar
  36. 36.
    Bush, E.T., Anal. Chem. 36: 1082 (1964).CrossRefGoogle Scholar

Copyright information

© New England Nuclear Corporation 1966

Authors and Affiliations

  • C. T. Peng
    • 1
  1. 1.Radioactivity Research Center and School of PharmacyUniversity of CaliforniaSan FranciscoUSA

Personalised recommendations