Download - Radiation Primer
Radiation Primer
“Electron Capture”
p + e- n + gamma ray ()
Gamma () Radiation
54Mn + e- 54Cr +
Extra Proton
p = ___n = ___
p = ___n = ___
DO THE MATH …
Gamma () Radiation
Gamma rays from cobalt-90 can pass through metals, and show
what’s inside — like the two stowaways in this truck.
60Co 60Ni + e- () + 2
Or, multiple beams can be focused on a tumor to kill it.
I’m a stowaway. I think I’ll just stand here a
while.
“Beta Decay”
n p + e- (beta particle )
Beta () Radiation
14C 14N + e-
Extra Neutron
p = ___n = ___
p = ___n = ___
DO THE MATH …
Soviet-era lighthouses used heat from radioactive strontium-90 to make electricity. Two hunters found a scrapped generator and slept near it for warmth. They died a couple of days later.
90Sr 90Y + e- ()
Beta () Radiation
Measure amount of beta radiation passing through material to measure thickness of
material.
Beta () Radiation
“Alpha Decay”
2n + 2p 4He (alpha particle )
Alpha () Radiation
226Ra 222Rn + 4He (alpha )
Extra Stuff
p = ___n = ___
p = ___n = ___
DO THE MATH …
p = ___n = ___
Former spy and Russian dissident Alexander Litvinenko was murdered by putting Polonium-
210 in his tea.
210Po 206Pb + 4He ()
Cigarettes can kill you with 210Po, too.
Alpha () Radiation
Background Radiation
= 3.6 mSv
80% is from natural sources !
Radon Levels
www.epa.gov/radon
Ashland 9.3 pCi/LMedina 3.6Lorain 4.7
Oklo “Reactor” (Gabon, Africa)
Enough uranium 2 billion years ago to allow natural nuclear fission reaction.
Uranium (1) dissolved & concentrated by groundwater.
Water acted like neutron target, but boiled off every 150 min. Cycle repeated for 100,000 years.
Rocks now look like used nuclear fuel.
Neon Isotope Half-LifeSTABLE
Too Man
y!Too Few!
JUST RIGHT !!!
Neon Isotope Half-LifeSTABLE
Too Man
y!
JUST RIGHT !!!What’s an
unbalanced isotope
gonna do?Too Few!
Turn some protons into
neutrons
Turn some neutrons
into protons
Neon Isotope Half-LifeSTABLE
Too Man
y!Too Few!
JUST RIGHT !!!
Too big? Lose some of BOTH