Improvements of FLUKA Calculation of the Neutron Albedo

Natacha Combier (1) , Arnaud Claret (1) , Philippe Laurent (1) , Vincent Maget (2) , Daniel Boscher (2) , Alfredo Ferrari (3) , Markus Brugger (3)

1 IRFU - Institut de Recherches sur les lois Fondamentales de l'Univers
2 ONERA - The French Aerospace Lab [Toulouse]
3 CERN [Genève]

This paper presents Monte-Carlo simulations based on the Fluka code aiming to calculate the contribution of the neutron albedo at a given date and altitude above the Earth chosen by the user. Results consist of a two-parameter distribution, the neutron energy and the angle to the tangent plane of the sphere containing the orbit of interest, and are provided by geographical position above the Earth at the chosen altitude. In this paper, a major improvement was introduced with respect to the previous model concerning the filtering of incoming cosmic rays hitting the upper atmosphere. This more accurate estimation of neutron albedo is of prime importance for the radiation belts modelers because it constitutes the main source of protons > 40 MeV of the inner radiation belt.

Mots clés: NEUTRONS; MAGNETOSPHERE; ALBEDO; COSMIC RAYS; CRAND; FLUKA

Domaines: Physique de l'espace [physics.space-ph]

Natacha Combier, Arnaud Claret, Philippe Laurent, Vincent Maget, Daniel Boscher, et al.. Improvements of FLUKA Calculation of the Neutron Albedo. IEEE Transactions on Nuclear Science, 2017, 64 (1), pp.614-621. ⟨10.1109/TNS.2016.2611019⟩. ⟨hal-01510381⟩