What are decays of subatomic particles?

Question

What are decays of subatomic particles?

Answer 1

Subatomic particle decay is mediated by the weak nuclear force.

The Weak Force nuclear force is one of the four fundamental forces experienced by elementary particles. As its name suggests, the weak force is some 10 billion (10^10) times weaker than electromagnetism. The weak force operates in certain decay processes of elementary particles. The well-known radioactive decay processes of alpha and beta decay are mediated by the weak nuclear force. Since the weak interaction is both very weak and very short range, its most noticeable effect is due to its other unique feature: flavour changing. Consider a neutron (quark content: UDD, or one up quark and two down quarks). Although the neutron is heavier than its sister nucleon, the proton (quark content UUD), it cannot decay into a proton without changing the flavour of one of its down quarks. Neither the strong interaction nor the electromagnetic allow flavour changing, so this must proceed by weak decay. In this process, a down quark in the neutron changes into an up quark by emitting a W boson, which then breaks up into a high-energy electron and an electron antineutrino. Since high-energy electrons are beta radiation, this is called beta decay.

Due to the weakness of the weak interaction, weak decays are much slower than strong or electromagnetic decays. For example, an electromagnetically decaying neutral pion has a life of about 10^−16 seconds; a weakly decaying charged pion lives about 10^−8 seconds, a hundred million times longer. A free neutron lives about 15 minutes, making it the unstable subatomic particle with the longest known mean life.

The weak force, like the other fundamental forces, can be described in terms of the exchange of particles. In the case of the weak force, there are three particles that can be involved. Two of these particles are electrically charged: the W+ and the W-. The third particle is neutral and is called the Z0. All three particles are bosons, meaning that they have zero spin. The W bosons have a mass of about 80 times that of the proton, while Z bosons have a mass about 90 times that of the proton. Due to the large mass of the weak interaction's carrier particles (about 90 GeV/c^2), their mean life is limited to about 3×10^−27 seconds by the uncertainty principle. Even at the speed of light this effectively limits the range of the weak interaction to 10^−18 meters, about 1000 times smaller than the diameter of an atomic nucleus.

Conservation of electrical charge implies that exchanging W's must give rise to a change in the charge, and therefore the identity, of the particles involved in the interaction. For example, if an electron neutrino (which is neutral) emits a W+, then to conserve charge the neutrino must change into a negatively charged particle. The rules governing the weak force dictate that this particle must be an electron. If a muon neutrino were to emit a W+, it would have to change into a negatively charged muon.

In 1979, the Nobel Prize for Physics was awarded to the US physicists Sheldon Glashow and Steven Weinberg and the Pakistani physicist Abdus Salam for showing how the weak force and electromagnetism are connected.

Answer 2

http://www.krysstal.com/subatomic.html

http://www.scienceclarified.com/Sp-Th/Su...

Answer 3

It's that nasty buildup between subatomic particles that brushing and flossing alone won't do................

Answer 4

I think you are talking about alpha decay, and beta decay . Alpha decay is when the radioactive atom releases an alpha particle, or a helium nucleus with 2 neutrons and 2 protons. Beta decay is when an electron or a positron is released along with an antineutrino or a neutrino. If its a neutron, then you get a proton, electron and an antineutrino. If its a proton, then you get a neutron, electron, and neutrino. Gamma rays are usually released with these decays.

Answer 5

Decays of subatomic particles occur when subatomic particles transform from one particle to another. The process is linked to the weak nuclear force and is mediated by the W boson.

For details on the process and some examples, see the link...

bye for now.

EDIT

Beta decay is NOT the same as particle decay. This (particle decay) is NOT the same as natural radioactive decay of the elements.

Also, mistress B is correct particle decay can be mediated by forces other than the weak nuclear. (thank you :-)

I have added the wiki link that is specific to particle decay.

Lastly, if wholeheartedly copying and pasting another site, please cite the source. Otherwise, it's plagiarism, plus, maybe we want to read more...!

http://en.wikipedia.org/wiki/Particle_de...

Answer 6

Since you are talking about subatomic particles, you are not referring to the decay of radioactive nuclei.

Subatomic particles, the electron, the proton and the neutron do not decay by themselves. But they can be transformed into energy by several processes.

1. The electron

Electrons can be transformed to energy by;

a. Electron Bremsstrahlung or electron braking action. When an electron passes near the field of an atomic nucleus its kinetic energy is released in the form of electromagnetic radiation. For every electron that comes to a dead stop its entire energy equivalent is released which is about 0.55  million electron volts.

b. Electron- Positron annihilation. When an electron collides with a positron, the two particles annihilate each other to nothingness converting their masses into electromagnitic radiation. The annihilation of an electron and a positron will yield and energy release of about 1.1 million electron volts in the form of gamma ray.

2. Proton - Proton collision.

a.The collision of two energitic protons can break the two particles into fragments such as bosons, fermions, muons, etc.

b. If fusion of the two particles occur in a non-elastic collision, the fusion may create a mini black hole.

3. Proton - Neutron collision. When a proton and a neutron collide they could bind to each other to form the nucleus of elements or isotopes heavier than the nucleus of hydrogen.

Answer 7

Could you be a little more specific about your question?  The general answer is that a decay is a reaction in which an unstable particle breaks into lighter, more stable pieces.

There are many, many subatomic particles, and they decay in different ways, by different mechanisms, into different things, on different time-scales.

Toddio and David: Subatomic particles can decay in various ways--some decay via the strong force, some via the weak force, and some electromagnetically.

Answer 8

the decays of subatomic particles are generally called beta decays. there can either be beta plus, or beta minus decay.

to explain thoroughly we have to introduce 2 new particles, the W+ and the W- bosons. they mediate what is called the weak nuclear force, and make these decays possible.

beta plus decay is a proton converting into a neutron and emitting a positron and a neutrino. the actual decay is the decay of a quark. an up quark decays into a down quark and a W+ boson. that W+ boson then decays into a positron and a neutrino.

beta minus decay is a neutron decaying into a proton, emitting an electron and an antineutrino. the actual equation again involves quarks. a down quark decays into an up quark and a W- boson. that W- boson then decays into an electron and an antineutrino.

other elementary particles can decay in ways that do not involve beta decay.

for example. the tau can decay into a tau neutrino, an electron, and an electron neutrino. or a tau neutrino, a muon, or a muon neutrino.

the muon can decay into an electron, an antielectron neutrino, and a muon neutrino.

top quarks decay into W+ bosons an either a down, strange, or bottom quark.

bottom quarks can decay into up or charmed quarks through the production of a W+ boson.

that pretty much covers it i think. i couldnt find the decays of strange or charmed quark, but your only missing the decays of 2 particles.