RE: WG: from energy density in GeV/cm3 to rad

Dear Anna,

in one of your last emails you asked also about "which parameters are
important for the radiation damage study". This is a vast field... to have
an idea about the variety of problems you can experience, hereafter you
find a short orientative summary (thanks to Markus Brugger that wrote it!)

- Energy/power density is 'damaging' in case stress to materials (or
sometimes already deformations) creates problems and this can range from
simple cooling problems to shockwave generation.
- Dose (ionizing dose) is a measure of ionizing radiation damage
(insulating materials, electronics, etc...). It is the easiest quantity as
well defined (as long as related to a material!) and well measurable
(again with certain constraints, especially when systems get very small or
large).
- Displacement damage is perhaps the most difficult: for electronics (but
also other applications) often defined through fluence conversion
coefficients giving 1MeV-neutron equivalent fluence as damage indicator
(simply due to the fact that in reactors damage is dominated by this, as
well as testing is easy). Real DPA is sometimes more complicated and
perhaps the most difficult quantity as 'direct measurements' are close to
(if not entirely) impossible.
- Fluence itself can be 'damaging' in case deposited/generated charge
exceeds threshold values (e.g., single event effects in electronics).

Last, to have an idea about the quantities that you can score in FLUKA to
evaluate the radiation damage to electronics, you can give a look at:

https://www.fluka.org/free_download/course/portugal2010/Lectures/AdvancedScoring2010.pdf
, pag. 16-19

kind regards

Anna

---------------------------------------------------------------
From: Kiseleva, Anna<A.Kiseleva_at_gsi.de>
Date: Fri, 14 Jan 2011 20:19:05 +0100

Dear FLUKA developers,

I hope, I understand now relation between both parameters:
energy density / dose = material density.
But which parameter more important =
for radiation damage study?

Best regards

Anna Kiseleva
Received on Mon Jan 17 2011 - 17:14:53 CET