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King_Ghidra
19-04-2005, 14:58:45
When radiation strikes a substance, such as a lead shield, what are the usual results? light, heat? Is anything else possible?

protein
19-04-2005, 14:59:48
What are you building Phil?

Should I move out of Reading?

King_Ghidra
19-04-2005, 15:00:56
no, no, just perhaps keep the curtains closed :nervous:

Funko
19-04-2005, 15:02:38
Now that's really not an easy question.

Basically... it depends on the type of radiation, the properties of that radiation and what it's hitting.

In general:

It could absorb a photon (gamma ray) and then emit some light/heat

It could create some other reaction, eg splitting an atom into two bits, forming a new atom of something else...

Funko
19-04-2005, 15:05:21
There are three types of radiation:

Alpha radiation - a helium nucleus, basically two neutrons and 2 protons with no electrons

Beta radiation - an electron

Gamma radiation - a photon (this is basically the series of things that includes infra red, visible light, x-rays, radio waves etc)

These three are very different things and how they react with stuff can be very different.

Cruddy
19-04-2005, 15:06:47
Originally posted by Funko



Gamma radiation - a photon

:lol:

Sorry Funko, but I really did laugh. And I could be wrong about this but...

...Electromagnetic radiation doesn't go in one offs. They travel in packets or quanta.

Gamma's the ultra short wavelength stuff. It goes all the way up through x-rays, uV, visible light, infra red, radio to ELF or Extreme Low Frequenc, used to transmit radio messages through the ocean.

MoSe
19-04-2005, 15:07:16
OK, you got a new space combat game with rather realistic and detailed parameters, and you must decide which armor apply (or eventually design to) on your spaceship hull

King_Ghidra
19-04-2005, 15:07:58
My cowie says:

<Evil>Shaft says:
Alpha radiation - 4He3 = charged particle
<Evil>Shaft says:
beta = e- free electron = charged particle
<Evil>Shaft says:
gamma = em radiation
<Evil>Shaft says:
neutron absorption = uncharged

King_Ghidra
19-04-2005, 15:08:45
he was just telling me about neutrons being produced by nuclear fission and how they would actually react with the chamber the reaction was being produced in

Funko
19-04-2005, 15:10:01
Yes, that's what I said but he's being more technical. :)

Funko
19-04-2005, 15:11:29
And I forgot about neutron absorption.

King_Ghidra
19-04-2005, 15:16:10
schoolboy error

Funko
19-04-2005, 15:17:29
It's boring.

Oooh look I absorbed a neutron. Zzzzzz.

King_Ghidra
19-04-2005, 15:18:53
:lol:

mr.G
19-04-2005, 15:19:21
absorb 2 neutrons and you become Swiss.

Cruddy
19-04-2005, 15:19:46
It's not exactly DIY science. But a lot of money goes into researching just what happens when energy hits matter.

Part of that money at CERN went into HTML... without which this thread wouldn't be. So it does result in some real benefits.

Funko
19-04-2005, 15:24:47
Originally posted by Cruddy
:lol:

Sorry Funko, but I really did laugh. And I could be wrong about this but...

...Electromagnetic radiation doesn't go in one offs. They travel in packets or quanta.

Yes, I know I didn't want to jump straight into wave particle duality or quantum mechanics.

This shit's confusing enough without learning it step by step, that's how we learnt it at school anyway, first learnt about the three different types of radiation then learnt it wasn't that simple and about the photoelectric effect / wave particle duality etc. later.

Quantum physics is a headfuck even if you understand all this stuff really well...

Funko
19-04-2005, 15:26:15
And anyway a photon is basically the name for a packet of electromagnetic energy...

More gamma basics here:

http://www.epa.gov/radiation/understand/gamma.htm

Cruddy
19-04-2005, 15:32:23
I agree, it's a headfuck. Like, photons don't have any mass when they're not moving - makes my head spin.

Venom
19-04-2005, 15:36:47
Originally posted by mr.G
absorb 2 neutrons and you become Swiss.

I think we're all missing the humor of this amongst the swarm of geeks having their intellectual dick measuring contest.

Cruddy
19-04-2005, 15:42:59
No, I saw it. I just didn't think it was funny.

Venom
19-04-2005, 15:45:07
Oh it's funny. As funny as anything gets around here.

Funko
19-04-2005, 15:45:51
K_G should tell the story of his friend hit by a neutron...

King_Ghidra
19-04-2005, 15:50:13
:lol:

Diss
19-04-2005, 20:45:08
Originally posted by Funko
There are three types of radiation:

Alpha radiation - a helium nucleus, basically two neutrons and 2 protons with no electrons

Beta radiation - an electron

Gamma radiation - a photon (this is basically the series of things that includes infra red, visible light, x-rays, radio waves etc)

These three are very different things and how they react with stuff can be very different.

there's also neutron radiation :p

those are the 4 main types they taught us in nuclear power school in the navy.

of course neutrons primarily come from nuclear reactions. Usually only a major concern when around nuclear power plants (or nuclear bomb detonations) or around highly radioactive metals such as uranium.

KrazyHorse@home
19-04-2005, 20:52:27
Originally posted by King_Ghidra
When radiation strikes a substance, such as a lead shield, what are the usual results? light, heat? Is anything else possible?

First off, it's important that you define what type of radiation you're talking about. Electrons, gammas, alphas, neutrons?

If the shield is thick enough most of the energy will be absorbed by the shield in the form of heat. Depending on the type of radiation there may also be some residual radioactivity contained in the shield itself. There will be some transmitted radiation through the shield in the form of gammas. Finally there will be some scatter off the surface of the shield. If a beam of radiation is directed onto a shield and you're standing off to the side watching it then you will get a pretty significant dose of gammas.

KrazyHorse@home
19-04-2005, 20:57:47
You might get to see some blue Cerenkov radiation if you're bombarding with extremely high energy electrons. Otherwise there will not be too much in the way of directly visible consequences.

If you get dosed with a huge amount of radiation then you will probably see some sort of flash and go blind. Then you'll live for a little bit (up to two weeks) as you develop radiation sickness, peritonitis, etc.