What characteristic makes heavier ions in GCRs biologically more damaging than equivalent energy from low-energy photons?

Answer

They deposit energy much more densely (high Linear Energy Transfer).

Heavy ions within GCRs have high Linear Energy Transfer (LET), meaning they deposit their energy very densely over a short path through tissue, making them far more biologically effective locally.

What characteristic makes heavier ions in GCRs biologically more damaging than equivalent energy from low-energy photons?
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