Enhanced soft X-ray detection efficiencies for imaging microchannel plate detectors

Abstract

Position-sensitive detectors using microchannel plate (MCP) electron multipliers have been widely used in X-ray astronomy1–3. Although MCPs facilitate X-ray imaging with high spatial resolution, as on the Einstein1 or EXOSAT3 satellites, their intrinsic soft X-ray detection efficiencies are low. These lie typically in the range 1–10% (ref. 4), much lower than the (near unity) values attainable with competing forms of gas proportional counter. To enhance sensitivity to X-ray energies below a few keV, a material of relatively high photoelectric yield may be deposited on the MCP front surface and channel walls. MgF2 has commonly fulfilled this role for X-ray astronomy1–3, resulting in enhanced efficiencies 1.1–1.6 times those of uncoated MCPs1. We report here high 0.18–1.5 keV X-ray detection efficiencies for MCPs bearing CsI deposition photocathodes. Efficiency enhancement factors, dependent on X-ray incident angle, of up to 15 times have been stably obtained. The importance of this work for the sensitivity of future X-ray astronomy experiments, such as the Röntgensatellit (ROSAT) Wide Field Camera, is outlined.

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References

  1. 1

    Henry, J. P. et al. Proc. SPIE 106, 196–206 (1977).

    ADS  Article  Google Scholar 

  2. 2

    Eng, W. & Landecker, P. B. Nucl. Instrum. Meth. 190, 149–157 (1981).

    ADS  CAS  Article  Google Scholar 

  3. 3

    Sanford, P. W. in New Instrumentation for Space Astronomy (eds Van der Hucht, K. A. & Vaiana, G.) 217–233 (Pergamon, Oxford, 1978).

    Google Scholar 

  4. 4

    Fraser, G. W. Nucl. Instrum. Meth. 195, 523–538 (1982).

    ADS  CAS  Article  Google Scholar 

  5. 5

    Wiza, J.-L. Nucl. Instrum. Meth. 162, 587–601 (1979).

    ADS  CAS  Article  Google Scholar 

  6. 6

    Smith, D. G. & Pounds, K. A. IEEE Trans. Nucl. Sci. NS- 15, 541–549 (1968).

    ADS  Article  Google Scholar 

  7. 7

    Fraser, G. W. Nucl. Instrum. Meth. (in the press).

  8. 8

    Bjorkholm, P. J., Van Speybroeck, L. P. & Hecht, M. Proc. SPIE 106, 189–195 (1977).

    ADS  CAS  Article  Google Scholar 

  9. 9

    Saloman, E. B., Pearlman, J. S. & Henke, B. L. Appl Opt. 19, 749–753 (1980).

    ADS  CAS  Article  Google Scholar 

  10. 10

    Aschenbach, B. et al. Space Sci. Rev. 30, 569–573 (1981).

    ADS  Article  Google Scholar 

  11. 11

    Advanced X-ray Astrophysics Facility (AXAF) Science Working Group Rep. (NASA Technical Memorandum TM 78285, 1980).

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Fraser, G., Barstow, M., Whiteley, M. et al. Enhanced soft X-ray detection efficiencies for imaging microchannel plate detectors. Nature 300, 509–511 (1982). https://doi.org/10.1038/300509a0

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