Skip to main content

Advertisement

Log in

GLE and Sub-GLE Redefinition in the Light of High-Altitude Polar Neutron Monitors

  • Published:
Solar Physics Aims and scope Submit manuscript

Abstract

The conventional definition of ground-level enhancement (GLE) events requires a detection of solar energetic particles (SEP) by at least two differently located neutron monitors. Some places are exceptionally well suitable for ground-based detection of SEP – high-elevation polar regions with negligible geomagnetic and reduced atmospheric energy/rigidity cutoffs. At present, there are two neutron-monitor stations in such locations on the Antarctic plateau: SOPO/SOPB (at Amundsen–Scott station, 2835 m elevation), and DOMC/DOMB (at Concordia station, 3233 m elevation). Since 2015, when the DOMC/DOMB station started continuous operation, a relatively weak SEP event that was not detected by sea-level neutron-monitor stations was registered by both SOPO/SOPB and DOMC/DOMB, and it was accordingly classified as a GLE. This would lead to a distortion of the homogeneity of the historic GLE list and the corresponding statistics. To address this issue, we propose to modify the GLE definition so that it maintains the homogeneity: A GLE event is registered when there are near-time coincident and statistically significant enhancements of the count rates of at least two differently located neutron monitors, including at least one neutron monitor near sea level and a corresponding enhancement in the proton flux measured by a space-borne instrument(s). Relatively weak SEP events registered only by high-altitude polar neutron monitors, but with no response from cosmic-ray stations at sea level, can be classified as sub-GLEs.

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

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Figure 1
Figure 2

Similar content being viewed by others

References

  • Aguilar, M., Aisa, D., Alpat, B., Alvino, A., Ambrosi, G., Andeen, K., et al.: 2015, Precision Measurement of the Proton Flux in Primary Cosmic Rays from Rigidity 1 GV to 1.8 TV with the Alpha Magnetic Spectrometer on the International Space Station. Phys. Rev. Lett. 114, 171103. DOI .

    Article  ADS  Google Scholar 

  • Atwell, W., Tylka, A.J., Dietrich, W., Rojdev, K., Matzkind, C.: 2015, Sub-GLE Solar Particle Events and the Implications for Lightly-Shielded Systems Flown During an Era of Low Solar Activity. In: Int. Conf. Environ. Sys., Lunar Planet. Sci. Conf. Proc. ntrs.nasa.gov/search.jsp?R=20150009484 .

    Google Scholar 

  • Clem, J.M., Dorman, L.I.: 2000, Neutron monitor response functions. Space Sci. Rev. 93, 335. DOI . ADS .

    Article  ADS  Google Scholar 

  • Dorman, L.: 2004, Cosmic rays in the Earth’s atmosphere and underground, Kluwer Academic, Dordrecht. 1-4020-2071-6.

    Book  Google Scholar 

  • Evenson, P., Bieber, J., Clem, J., Pyle, R.: 2011, South Pole Neutron Monitor Lives Again. In: Proc. Int. Cosmic Ray Conf. 11, 459. DOI . ADS .

    Google Scholar 

  • Flückiger, E.O., Moser, M.R., Pirard, B., Bütikofer, R., Desorgher, L.: 2008, A parameterized neutron monitor yield function for space weather applications. In: Caballero, R., D’Olivo, J.C., Medina-Tanco, G., Nellen, L., Sánchez, F.A., Valdés-Galicia, J.F. (eds.) Proc. 30th Int. Cosmic Ray Conf. 1, 289. ADS .

    Google Scholar 

  • Forbush, S.E.: 1946, Three Unusual Cosmic-Ray Increases Possibly Due to Charged Particles from the Sun. Phys. Rev. 70, 771. DOI . ADS .

    Article  ADS  Google Scholar 

  • Forbush, S.E., Stinchcomb, T.B., Schein, M.: 1950, The Extraordinary Increase of Cosmic-Ray Intensity on November 19, 1949. Phys. Rev. 79, 501. DOI . ADS .

    Article  ADS  Google Scholar 

  • Gopalswamy, N., Xie, H., Akiyama, S., Mäkelä, P.A., Yashiro, S.: 2014, Major solar eruptions and high-energy particle events during solar cycle 24. Earth Planets Space 66, 104. DOI . ADS .

    Article  ADS  Google Scholar 

  • Grieder, P.K.F.: 2001, Cosmic Rays at Earth, Elsevier Science, Amsterdam. ADS .

    Google Scholar 

  • Mishev, A.L., Kocharov, L.G., Usoskin, I.G.: 2014, Analysis of the ground level enhancement on 17 May 2012 using data from the global neutron monitor network. J. Geophys. Res., Space Phys. 119(2), 670. DOI .

    Article  ADS  Google Scholar 

  • Mishev, A., Poluianov, S., Usoskin, I.: 2017, Assessment of spectral and angular characteristics of sub-GLE events using the global neutron monitor network. J. Space Weather Space Clim. 7, A28. DOI .

    Article  ADS  Google Scholar 

  • Mishev, A., Usoskin, I.: 2016, Analysis of the Ground-Level Enhancements on 14 July 2000 and 13 December 2006 Using Neutron Monitor Data. Solar Phys. 291, 1225. DOI . ADS .

    Article  ADS  Google Scholar 

  • Nevalainen, J., Usoskin, I., Mishev, A.: 2013, Eccentric dipole approximation of the geomagnetic field: Application to cosmic ray computations. Adv. Space Res. 52(1), 22. DOI .

    Article  ADS  Google Scholar 

  • Picozza, P., Galper, A.M., Castellini, G., Adriani, O., Altamura, G., Ambriola, M., et al.: 2007, PAMELA – a payload for antimatter matter exploration and light-nuclei astrophysics. Astropart. Phys. 27(4), 296. DOI .

    Article  ADS  Google Scholar 

  • Poluianov, S., Usoskin, I., Mishev, A., Moraal, H., Kruger, H., Casasanta, G., Traversi, R., Udisti, R.: 2015, Mini Neutron Monitors at Concordia Research Station, Central Antarctica. J. Astron. Space Sci. 32, 281. DOI . ADS .

    Article  ADS  Google Scholar 

  • Raukunen, O., Vainio, R., Tylka, A.J., Dietrich, W.F., Jiggens, P., Heynderickx, D., Dierckxsens, M., Crosby, N., Ganse, U., Siipola, R.: 2017, Two solar proton fluence models based on ground level enhancement observations. J. Space Weather Space Clim., submitted.

  • Simpson, J.A.: 1990, Astrophysical Phenomena Discovered by Cosmic Ray and Solar Flare Ground Level Events: The Early Years. In: Proc. Int. Cosmic Ray Conf. 12, 187. ADS .

    Google Scholar 

  • Smart, D.F., Shea, M.A.: 2009, Fifty years of progress in geomagnetic cutoff rigidity determinations. Adv. Space Res. 44(10), 1107. DOI .

    Article  ADS  Google Scholar 

  • Souvatzoglou, G., Mavromichalaki, H., Sarlanis, C., Mariatos, G., Belov, A., Eroshenko, E., Yanke, V.: 2009, Real-time GLE alert in the ANMODAP Center for December 13, 2006. Adv. Space Res. 43(4), 728. Solar Extreme Events: Fundamental Science and Applied Aspects. DOI .

    Article  ADS  Google Scholar 

  • Tylka, A.J., Dietrich, W.F.: 2009, A new and comprehensive analysis of proton spectra in ground-level enhanced (GLE) solar particle events. In: Proc. 31th Int. Cosmic Ray Conf., Lodz. icrc2009.uni.lodz.pl/proc/pdf/icrc0273.pdf .

    Google Scholar 

  • Vainio, R., Raukunen, O., Tylka, A.J., Dietrich, W.F., Afanasiev, A.: 2017, Why is solar cycle 24 an inefficient producer of high-energy particle events? Astron. Astrophys. 604, A47. DOI . ADS .

    Article  ADS  Google Scholar 

  • Vashenyuk, E.V., Balabin, Y.V., Stoker, P.H.: 2007, Responses to solar cosmic rays of neutron monitors of a various design. Adv. Space Res. 40(3), 331. DOI .

    Article  ADS  Google Scholar 

Download references

Acknowledgements

The work was supported by the projects of the Academy of Finland Centre of Excellence ReSoLVE (No. 272157), CRIPA and CRIPA-X (No. 304435), and by the Finnish Antarctic Research Program (FINNARP). We acknowledge Askar Ibragimov for the support of the International GLE database ( gle.oulu.fi ) and are grateful to the worldwide neutron-monitor database ( nmdb.eu ), which is a product of an EU Project. We thank Marc Duldig, Erwin Flückiger, John Humble, and Roger Pyle for valuable discussions.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to S. V. Poluianov.

Ethics declarations

Disclosure of Potential Conflicts of Interest

The authors declare that they have no conflicts of interest.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Poluianov, S.V., Usoskin, I.G., Mishev, A.L. et al. GLE and Sub-GLE Redefinition in the Light of High-Altitude Polar Neutron Monitors. Sol Phys 292, 176 (2017). https://doi.org/10.1007/s11207-017-1202-4

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1007/s11207-017-1202-4

Keywords

Navigation