SwePub
Sök i SwePub databas

  Extended search

Träfflista för sökning "WFRF:(Heber B.) srt2:(2009)"

Search: WFRF:(Heber B.) > (2009)

  • Result 1-2 of 2
Sort/group result
   
EnumerationReferenceCoverFind
1.
  • Matthia, D., et al. (author)
  • Temporal and spatial evolution of the solar energetic particle event on 20 January 2005 and resulting radiation doses in aviation
  • 2009
  • In: Journal of Geophysical Research. - 0148-0227 .- 2156-2202. ; 114:8, s. A08104 (art no)-
  • Journal article (peer-reviewed)abstract
    • The solar energetic particle event on 20 January 2005 was one of the largest ground level events ever observed. Neutron monitor stations in the Antarctic recorded count rate increases of several thousand percent caused by secondary energetic particles, and it took more than 36 h to return to background level. Such huge increases in high energetic solar cosmic radiation on the ground are obviously accompanied by considerable changes in the radiation environment at aviation altitudes. Measurements of 28 neutron monitor stations were used in this work to numerically approximate the primary solar proton spectra during the first 12 h of the event by minimizing the differences between measurements and the results of Monte-Carlo calculated count rate increases. The primary spectrum of solar energetic protons was approximated by a power law in rigidity and a linear angular distribution. The incoming direction of the solar energetic particles was determined and compared to the interplanetary magnetic field direction during the event. The effects on the radiation exposure at altitudes of about 12 km during that time were estimated to range from none at low latitudes up to almost 2 mSv/h for a very short time in the Antarctic region and about 0.1 mSv/h at high latitudes on the Northern Hemisphere. After 12 h, dose rates were still increased by 50% at latitudes above 60 degrees whereas no increases at all occurred at latitudes below 40 degrees during the whole event.
  •  
2.
  • Matthiä, Daniel, et al. (author)
  • The Ground Level Event 70 on December 13th, 2006 and Related Effective Doses at Aviation Altitudes
  • 2009
  • In: Radiation Protection Dosimetry. - : Oxford University Press (OUP). - 0144-8420 .- 1742-3406. ; 136:4, s. 304-310
  • Journal article (peer-reviewed)abstract
    • The 70th ground level event in the records of the Neutron Monitor network occurred on 13 December 2006 reaching a maximum count rate increase at the Oulu station of more than 90% during the 5 min interval 3.05-3.10 UTC. Thereafter, count rates gradually decreased registering increases of a few per cent above the galactic cosmic ray background after a few hours. The primary proton spectrum during the first 6 h after the onset of the event is characterised in this work by fitting the energy and angular distribution by a power law in rigidity and a linear dependence in the pitch angle using a minimisation technique. The results were obtained by analysing the data from 28 Neutron Monitor stations. At very high northern and southern latitudes, the effective dose rates were estimated to reach values of 25-30 mu Sv h(-1) at atmospheric depth of 200 g cm(-2) during the maximum of the event. The increase in effective dose during north atlantic and polar flights was estimated to be in the order of 20 %.
  •  
Skapa referenser, mejla, bekava och länka
  • Result 1-2 of 2
Type of publication
journal article (2)
Type of content
peer-reviewed (2)
Author/Editor
Berger, T. (2)
Meier, M. (2)
Sihver, Lembit, 1962 (2)
Reitz, G. (2)
Heber, B. (2)
Herbst, K. (1)
show more...
Matthia, D. (1)
Matthiä, Daniel (1)
show less...
University
Chalmers University of Technology (2)
Language
English (2)
Research subject (UKÄ/SCB)
Natural sciences (2)
Year
2009 (2)Undo refine

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.

 
pil uppåt Close

Copy and save the link in order to return to this view