1

I am looking for how to compute the thickness of shielding materials and have found the following research: ISNPS Technical Report ISNPS-1-2013 Tai and El-Genk.doc (unm.edu)

The report is mentions the „highest ionizing energy deposition." I have no idea what it is and how to interpret this data.

enter image description here

JRE
  • 67,678
  • 8
  • 104
  • 179
Anna Koroleva
  • 227
  • 1
  • 6
  • Simplistically, the greater the density of a material, the better it is at radiation shielding for a given thickness. – SteveSh Mar 11 '22 at 13:25

2 Answers2

0

"Ionizing energy deposition" is the amount of energy that is lost by a subatomic particle as it passes through some material. The energy lost by the particle is absorbed by the material that it passes through. When you are specifying a radiation shield you want high energy deposition because that means lower energy remaining in the particles, if any, that pass through the shield.

Elliot Alderson
  • 31,192
  • 5
  • 29
  • 67
  • In the context of what OP posted, I think the "Ionizing energy deposition" refers to what is deposited in the ideal silicon sphere. So then lower would be better if my interpretation is correct. – SteveSh Mar 11 '22 at 13:28
  • @SteveSh Ah, I didn't realize that the silicon sphere was the thing being shielded. You are correct. – Elliot Alderson Mar 11 '22 at 15:30
  • Yeah, I had to stare at the post for a bit to reach that conclusion. – SteveSh Mar 11 '22 at 15:45
0

The silicon sphere is a target that is a stand-in for the electronics being protected from radiation by the shield.

The energy deposition concept applies to the sphere: the less energy deposition [in the sphere], the better the shielding must have been.

The article snippet implies that the primary radiation source, external to the shield, can cause secondary emission from the shield material. This secondary emission varies depending on shield materials and thicknesses. For example, with an aluminum shield, thicknesses above 10g/cm^2 have secondary proton emission that the effective dose received by the target sphere is higher.

Kuba hasn't forgotten Monica
  • 32,734
  • 1
  • 38
  • 103