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SR-NIEL – 7

Screened Relativistic (SR) Treatment for NIEL Dose

Nuclear and Electronic Stopping Power Calculator

(version 10.14)

Proton High AMS02 small

Incident Particle:
Target Materials
Target Selection:
N° Elements:
Target Material Z Stoichiometric Index or Element Fraction
Recoil Energy Eener: [MeV]
Spectral Fluence
values:
use dot "." as decimal separator;
at least, a pair (energy and spectral fluence) of values are required
Energy
[MeV]
Spectral Fluence
[cm-2 MeV-1]


EXAMPLE:
Copy and paste the data here to reproduce the following example.
Protons nuclear recoil probability in Si with Eener=0.1 MeV (red) and protons spectral fluence (blue) assuming an orbit around Jupiter, at Europa altitude, during 1 year mission moderated by 4mm of Al:

Spectral fluence data are calculated with JOREM Model implemented in SPENVIS
assuming a 1 sr solid angle exposure.

NOTE:
  • The sr-treatment has accuracy of about some percent at 50-200 keV/nucleon (see Sect 2.2.2 in [Leroy and Rancoita (2016)]).
  • Within sr-treatment, the Probability (per cm2) for a fluence of protons or ions to generate a recoil nuclei above the requested Eener value is derived by

    (total probability in g-1) x (absorber density in g cm-3) x (traversed thickness in cm),

    where the "total probability in g-1" is obtained by the web calculator, absorber density and traversed thickness are defined by the user; Eener is the the lower limit of recoil energy (for explanation see Energetic Nuclear Recoil Page)
  • The Probability (per cm2) depends on the energy of the incoming particle.
  • Energetic nuclear recoil probability for compounds can be determined by means of Bragg's rule, i.e., the overall Probability in units of cm2/g is obtained as a weighted sum in which each material contributes proportionally to the fraction of its atomic weight. An example for selection, with water (H2O) as target, follows:

    or equivalently