The Malter effect is named after Louis Malter, who first described the effect. Following exposure to ionizing radiation (e.g., electrons, ions, X-rays, extreme ultraviolet, vacuum ultraviolet), secondary electron emission from the surface of a thin insulating layer results in the establishment of a positive charge on the surface. This positive charge produces a high electric field in the insulator, resulting in the emission of electrons through the surface. This tends to pull more electrons from further beneath the surface. Eventually the sample replenishes the lost electrons, by picking up the collected secondary electrons through the ground loop.[1][2]

The Malter effect[3][4][5] often arises in wire chambers (aka drift chambers). After six years of operation, the BES III science team reported on a serious problem caused by the effect and how they coped with the problem.[6]

For cathode aging, a polymer formation deposits on the cathode surfaces. This insulating layer prevents the neutralization of positive ions, leading to the formation of a surface charge. The charge induces a high electric field which can be enhanced enough to extract electrons from the cathode. Most of them recombine with positive ions immediately, but some of them drift to the anode and generate avalanches at the sense wire. The avalanche positive ions come back to the cathode, enhance the electric field of the insulating layer, and thus feed a continuous, self-sustaining local discharge in the chamber without external irradiation. This effect is called the Malter effect ...[6]

References

  1. ↑ Peter W. Hawkes (1992). Advances in electronics and electron physics. Academic Press. pp. 34–. ISBN 978-0-12-014725-0. Retrieved 10 March 2012.
  2. ↑ American Institute of Electrical Engineers; Institute of Electrical and Electronics Engineers (July 1980). Radio engineering and electronic physics. American Institute of Electrical Engineers. Retrieved 10 March 2012.
  3. ↑ Kolanoski, Hermann; Wermes, Norbert (30 June 2020). Particle Detectors: Fundamentals and Applications. Oxford University Press. p. 251. ISBN 978-0-19-189923-2.
  4. ↑ Ballentyne, D. W. G.; Lovett, D. R. (6 December 2012). "Malter Effect". A Dictionary of Named Effects and Laws in Chemistry, Physics and Mathematics (4th ed.). Springer. ISBN 9789401160285.
  5. ↑ Nappi, Eugenio; Sequinot, Jacques, eds. (10 August 2004). "Radiation Damage and Long Term Ageing in Gas Detectors by M. Titov". Innovative Detectors for Supercolliders, Proceedings of the 42nd Workshop of the Infn Eloisatron Project. World Scientific. pp. 199–226. ISBN 9789814483322. (See p. 202.)
  6. 1 2 Dong, M.Y.; Xiu, Q.L.; Wu, L.H.; Wu, Z.; Qin, Z.H.; Shen, P.; An, F.F.; Ju, X.D.; Liu, Y.; Zhu, K.; Ouyang, Q.; Chen, Y.B. (17 Aug 2015). "Aging effect in the BESIII drift chamber". Chinese Physics C. 40: 016001. arXiv:1504.04681. doi:10.1088/1674-1137/40/1/016001. S2CID 118327562.

Bibliography


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