The Secondary Photoelectron effect intro

The Secondary Photoelectron effect;
an introduction

Albert Einstein won the 1921 Nobel Prize for Physics for his work on the photoelectric effect Ė the fact that photoelectrons are emitted from atoms when they absorb energy from light. This discovery led to the quantum revolution.

It isnít only visible light that produces this effect; ionizing radiation does it too. Gamma rays, being more penetrating, will produce it deep in body tissue where visible light doesnít reach. Crucially for nuclear power and nuclear weapons, elements of high atomic number, like Uranium, are far more effective at absorbing gamma rays than the far less massive elements out of which our bodies are made.

Insoluble Uranium Oxide particles from Uranium weapons readily become lodged in human tissue. There they act like antennae, absorbing photons from natural gamma background and re-emitting the energy in the form of photoelectrons which are indistinguishable from beta radiation. Soluble Uranium dissolved in food and water tends to be strongly attached to phosphate in DNA because living systems use it in place of calcium. This means that photoelectrons are emitted exactly where they will cause the most genetic damage.
New Scientist has published a major report on the health implications of using Uranium weapons.

Radiation protection agencies like Public Health England and the Environment Agency view Uranium as a low hazard because it isnít very radioactive. However, it has been calculated (1) that the photoelectrons created by the Secondary Photoelectron effect are 1500 times more damaging than the alpha particles produced by the radioactive decay of Uranium.

The next page gives more on the scientific concepts.

1 Busby Chris and Schnug Ewald (2008) Advanced biochemical and biophysical aspects of uranium contamination. In: (Eds) De Kok, L.J. and Schnug, E. Loads and Fate of Fertilizer Derived Uranium. Backhuys Publishers, Leiden, The Netherlands, ISBN/EAN 978-90-5782-193-6.

2 Mobbs SF, Muirhead CR, Harrison JD (2011) Risks from ionising radiation: an HPA viewpoint paper for Safegrounds. J. Radiol. Prot. 31:289-307.

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