Space Science Reviews

, Volume 93, Issue 1–2, pp 335–359 | Cite as

Neutron Monitor Response Functions

  • John M. Clem
  • Lev I. Dorman


The neutron monitor provides continuous ground-based recording of the hadronic component in atmospheric secondary radiation which is related to primary cosmic rays. Simpson (1948) discovered that the latitude variation of the secondary hadronic component was considerably larger than the muon component suggesting the response of a neutron monitor is more sensitive to lower energies in the primary spectrum. The different methods of determining the neutron monitor response function of primary cosmic rays are reviewed and discussed including early and recent results. The authors also provide results from a new calculation (Clem, 1999) including angle dependent yield functions for different neutron monitor types which are calculated using a simulation of cosmic ray air showers combined with a detection efficiency simulation for different secondary particle species. Results are shown for IGY and NM64 configurations using the standard 10BF3 detectors and the new 3He detectors to be used in the Spaceship Earth Project (Bieber et al., 1995). The method of calculation is described in detail and the results are compared with measurements and previous calculations. A summary of future goals is discussed.


Yield Function Neutron Monitor Primary Spectrum Solar Neutron Geomagnetic Cutoff 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Kluwer Academic Publishers 2000

Authors and Affiliations

  • John M. Clem
    • 1
  • Lev I. Dorman
    • 2
  1. 1.Bartol Research InstituteUniversity of DelawareNewarkU.S.A.
  2. 2.IZMIRANMoscowRussia

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