Sunday, September 26, 2010

Radioactive decay

Okay something easier this time. I'm going to talk about the different types of radioactive decay. I won't go into much detail, just explain what happens. I'll explain why it happens in another post, faggot.

So what is radioactivity? It's when an unstable nucleus decays into something else while shitting out a vile array of other shit. In order to respect the laws of conservation of energy/charge/momentum etc this decay can only happen in certain ways. Before we look at the different types of radiation, first I need to explain why the fucking nucleus was unstable in the first place, that cunt.

Any given nucleus is made up of protons and neutrons. Protons have a positive charge, which means if you have two of them, they push each other away, like fucking magnets. Neutrons have no charge, they're gay. So at the heart of the nucleus there are electromagnetic forces pushing away and generally trying to rip shit apart. So what keeps it together? The answer is the strong nuclear force, oh hell yeah. This is an incredibly powerful force that acts at extremely close range. It's responsible for making nucleons stick together on contact. It's the fucking badass of fundamental interactions.

So basically there's a competition between the electromagnetic force trying to fuck shit up, and the strong force keeping stuff together.

This is where the instabilty comes from. Sometimes the nucleus can't hold together anymore and so it has to decay into something which is stable. Let's go through the different ways of doing this:

Alpha decay: Ok, first one. Typically this occurs when an element is too heavy. Imagine a fucking fat-ass element with a shit load of protons and neutrons barely held together. This fatty needs to shead some fucking weight. So it emits an alpha particle. An alpha particle is just a Helium nucleus: 2 protons and 2 neutrons. It loses a total of 4 nucleons in weight. It's a bit like taking a nuclear shit. Alpha radiation is an emission of helium nuclei.

X → Y + α

β decay: This happens when the nucleus has too many neutrons and not enough protons (I know this seems to contradict what I said before about stability but it's hard to explain). So what happens? It needs to become less homosex, so one of the neutrons turns into a proton, while emitting an electron and an antineutrino. β radiation is an emission of electrons.

neutron → proton + electron + antineutrino

Or:         n → p + e + νe

β+ decay: This happens when the nucleus has too many protons and not enough neutrons. What happens? One of the protons turns into a neutron while emitting an antielectron (=positron) and a neutrino. β+ radiation is an emission of antielectrons.

Proton → neutron + antielectron + neutrino

Or:       p → n + e+ + νe

γ decay: This happens when a nucleus finds itself in an excited or energised state. In order to lose this extra energy it has to emit some sort of particle. This particle is called a gamma ray. It's actually just a photon, the particle that carries light, but way the fuck more energetic. Gamma radiation is an emission of photons in the gamma range.

E* → E + γ

Okay so that's the short explanation of the most commons types of decay. If you must know there are other sorts of decay that can occur too, but they are extremely rare compared to these 4. The other types are known as exotic decay.

Some of the explanations are a bit simplified so don't nerd-rage in the comments okay? I can explain how dangerous they all are later.

Next time I'll explain exactly why decay occurs, it's all to do with quantum mechanics and bullshit. Ask questions in the comments if I didn't explain something properly, I kind of rushed this one. Take care guys.

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