Radiation/Matter Interaction and
Electromagnetic Couplings

Radiation/matter interaction

The interaction of photons, neutrons, electrons, heavy ions and protons with matter is well mastered by NUCLETUDES from both the understanding and modeling points of view.

On these topics NUCLETUDES utilizes the following software applications:

 Geant4 software is also used for specific analyses regarding electronical applications.

These software applications are used to:

• compute the energy deposition induced by the particles,
• evaluate the shielding level required to protect the most sensitive elements.
  

In the specific case where radiations are produced by a nuclear explosion, the available software applications allow for:

• simulating the X-rays and gamma rays propagation in the atmosphere,
• modeling the propagation of the electrons produced by these photons/matter interactions, taking into account their interaction with the air (secondary electrons) and the effect of the Earth magnetic field.

Electromagnetic couplings

From this definition of the radiation environment and associated radiation/matter interactions, NUCLETUDES has the capacity to precisely model the electromagnetic couplings occurring after a nuclear explosion at both system and equipment (equipment case, cables, harness, electronical cards) levels, and in particular the environments induced locally by :

A High Altitude nuclear explosion:

- Affecting systems located:

• in the ground or at low altitude : High Altitude ElectroMagnetic Pulse or HA EMP,
• in the gamma source area : Source Region EMP or SREMP,
• in the X-rays source zone or above the source zone area : SGEMP (System-Generated ElectroMagnetic Pulse) effects generated by the impact of X rays on the system or equipment, extracting electrons by photoelectric effect and creating high level transient EM fields and currents,

 
      •   in orbit and submitted to a trans-horizon effect (Dispersed EMP or DEMP).

A Low Altitude nuclear explosion:

NUCLETUDES has also developed accurate competencies on :

• lightning-hardened systems (current injection), 
• the effects of nuclear weapons, 
• vulnerability issues linked to Directed Energy Weapons such as High Power MicroWaves.
  

At last, it has to be noted that the in-house development of various software tools modeling these different phenomena has led NUCLETUDES to invest significantly in the development of innovative numerical methods.

These in-house software models have been validated through various experimental tests using NULETUDES’ own see test facilities as well as external test facilities (CEA,…).