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Hluf
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I'm a new comer to study the hadron physics.Why light quarks are more stable than heavy quarks and which one is easy to study? why? Thank you
A quark (or any other particle) can only decay into a lighter quark.Hluf said:I'm a new comer to study the hadron physics.Why light quarks are more stable than heavy quarks and which one is easy to study? why? Thank you
The light quarks do not exist as isolated particles, they are always bound in hadrons*. For light quarks, you have to consider the mass of the hadron - and the proton (with two up-quarks and one down-quark) is stable**. Neutrons (with two down-quarks and one up-quark) can be stable as part of nuclei.clem said:A quark (or any other particle) can only decay into a lighter quark.
Only the lightest u quark is stable.
Depends on the property you want to study.Hluf said:and which one is easy to study?
RocketSci5KN said:Are there any good theories why neutrons in *most* nucleii are somehow stabilized against beta decay
It is mainly due to the strong force and energy conservation, see jtbell's post.RocketSci5KN said:Are there any good theories why neutrons in *most* nucleii are somehow stabilized against beta decay, whereas free neutrons have a known half-life? I'd like something better than 'it's all due to the weak force'...
There is no free form.Also, would the light quarks theoretically be stable in their free form?
- the particles are called pions, not puonsChrisVer said:What helped me in that was that image- I don't know whether it's correct or not but it makes sense-.
Suppose you have a free neutron, it will remain a neutron forever (not interacting) until it decomposes due to beta decay. Beta decay is a weak interaction process, so it's characteristic time is generally larger than the strong's interaction.
Now suppose that the neutron is in the nuclei. What happens then? it interacts with the protons, via puons (Yukawa mesons). If you draw the procedure of that, you will see that the proton at point A emits a puon, becoming a neutron, and the neutron at point B receives the puon and becomes a proton. And this goes on and on. So in fact you never have one neutron waiting to decay. The neutrons change with protons over and over again in times of order of strong interaction characteristic time which is mass lesser than the weak's.
So by that image, the neutron will be stable in the nuclei because strong interactions don't allow it to decay.
A quark is a subatomic particle that is considered to be one of the fundamental building blocks of matter. It is important to study its stability because quarks are the basic components of protons and neutrons, which make up the nucleus of an atom. Understanding the stability of quarks can help us understand the properties and behavior of matter at a fundamental level.
Light quarks refer to the up, down, and strange quarks, which have relatively low masses. Heavy quarks, on the other hand, refer to the charm, bottom, and top quarks, which have significantly higher masses. The difference in mass affects the stability and behavior of these quarks, making them important to study separately.
Scientists use particle accelerators to study the behavior of quarks by colliding particles at high speeds. By analyzing the products of these collisions, scientists can observe how quarks interact and decay, providing insights into their stability.
Studying quark stability can have applications in various fields such as nuclear physics, particle physics, and cosmology. It can help us understand the properties of matter and how the universe evolved after the Big Bang. It can also have practical applications in technology, such as improving particle accelerators and developing new materials.
The Standard Model of particle physics is the current theory that describes the behavior and interactions of quarks. It predicts that quarks are stable particles and cannot exist independently. However, some theories suggest the existence of subatomic particles called "preons" that could explain the stability of quarks. Further research and experiments are needed to confirm these theories.