Cherenkov radiation from neutral composite particles

In summary, the conversation discusses the possibility of atomic or subatomic neutral composite particles emitting cherenkov radiation if they are polarized strongly enough and moving at a high speed. However, it is unlikely for this to occur due to disintegration or other factors. The conversation also touches on the magnetic dipole moments of neutrons and neutral mesons, and the mechanisms for elastic scattering of neutrons and electrons. It is mentioned that color confinement does not necessarily prevent disintegration, and that mesons with spin zero may not possess a net magnetic moment due to symmetry. The conversation also addresses the concept of total angular momentum and its relation to magnetic moments.
  • #1
Garlic
Gold Member
181
72
Hello everyone,
Can atomic or subatomic neutral composite particles that consist charged particles emit cherenkov radiation if they are polarised strongly enough (and are fast enough)?
 
Physics news on Phys.org
  • #2
It's not impossible, but long before you get your first Cherenkov photon the compound disintegrates from scattering in the medium, loses all its energy or does something else that has nothing to do with Cherenkov radiation.
 
  • #3
mfb said:
It's not impossible, but long before you get your first Cherenkov photon the compound disintegrates from scattering in the medium,
What if the composite particle cannot disintegrate because of colour confinement?

Neutrons have a magnetic dipole moment. Do neutral mesons also possesses magnetic dipole moments?

Neutrons are capable of elastic scattering off a proton via strong interaction. But electrons are not subject to strong interaction. What is the prevalent mechanism for elastic scattering of neutrons from electrons: electromagnetic interaction with the magnetic dipole moment, or weak interaction?
 
  • #4
snorkack said:
What if the composite particle cannot disintegrate because of colour confinement?
Color confinement doesn't prevent anything if there is sufficient energy. On the other hand, color confined objects are too small for Cherenkov radiation anyway.
snorkack said:
Do neutral mesons also possesses magnetic dipole moments?
I would expect that, unless there is a symmetry preventing it.
 
  • #5
mfb said:
I would expect that, unless there is a symmetry preventing it.

Spin-0 mesons have a symmetry preventing it. (In which direction does the moment point?) Spin-1 and higher don't have this problem, but they are too short lived to have a substantial interaction with a magnetic field. The best you can usually do is measure a transition magnetic moment.
 
  • Like
Likes mfb
  • #6
Vanadium 50 said:
Spin-0 mesons have a symmetry preventing it. (In which direction does the moment point?)
Hydrogen atom does have a magnetic dipole moment - despite having spin zero. The spins of proton and electron are opposite and equally half, so cancel to zero - the magnetic moments of proton and electron are unequal, and leave a net magnetic moment.
Why then cannot a meson with spin zero consisting of two different quarks possesses a net magnetic moment?
 
  • #7
snorkack said:
Hydrogen atom does have a magnetic dipole moment - despite having spin zero.

Are you sure? What is [itex]\sqrt{l(l+1)}[/itex] in this case?
 
  • #8
Vanadium 50 said:
Are you sure? What is [itex]\sqrt{l(l+1)}[/itex] in this case?
What are you signifying with l here?
 
  • #9
L is total angular momentum. Zero for parahydrogen.
 
  • #10
Indeed. Zero total angular momentum because the spins of electron and proton are antiparallel and equal. Whereas the magnetic momenta are unequal, and actually in the same direction.

If electron and proton can have net magnetic moment despite having spin summed to zero, why cannot two quarks which are not each other´s antiparticles have a net magnetic moment despite having spin summed to zero?
 
  • #11
If you are in an eigenstate of total spin, the individual spins are in a state [itex]\uparrow \downarrow + \downarrow \uparrow [/itex]. When you operate the magnetic moment operator on that wavefunction, you get zero.

If you place this atom in a magnetic field, you will polarize the electron, sure. But now you are in an eignestate of electron spin and not in an eigenstate of total angular momentum.
 
  • #12
snorkack said:
Hydrogen atom does have a magnetic dipole moment - despite having spin zero.

I don't think so. A spin zero state is completely rotationally symmetric, so can't have a moment pointing in any particular direction.
 
  • Like
Likes vanhees71

1) What is Cherenkov radiation from neutral composite particles?

Cherenkov radiation from neutral composite particles is a type of electromagnetic radiation that is produced when charged particles pass through a medium at a speed greater than the speed of light in that medium. This phenomenon is named after Soviet physicist Pavel Cherenkov, who first observed it in 1934.

2) How is Cherenkov radiation from neutral composite particles different from other types of electromagnetic radiation?

Unlike other types of electromagnetic radiation, which are produced by the acceleration of charged particles, Cherenkov radiation is produced by the passage of charged particles through a medium. Additionally, Cherenkov radiation has a characteristic blue glow, while other types of radiation may have different colors or no visible light at all.

3) What are some practical applications of Cherenkov radiation from neutral composite particles?

Cherenkov radiation has many applications in various fields of science, including nuclear and particle physics, astrophysics, and medical imaging. It is also used in particle detectors, such as the Cherenkov Telescope Array, which is used to study high-energy gamma rays from outer space.

4) Can Cherenkov radiation from neutral composite particles be dangerous to humans?

In most cases, Cherenkov radiation from neutral composite particles is not dangerous to humans. The intensity of the radiation is relatively low and it can be shielded by materials such as water or concrete. However, in certain situations, such as in nuclear reactors, the radiation can be harmful and must be carefully monitored and controlled.

5) How is Cherenkov radiation from neutral composite particles detected and measured?

Cherenkov radiation is typically detected and measured using specialized detectors, such as photomultiplier tubes, which are sensitive to the blue light emitted by the radiation. The intensity and spectrum of the radiation can then be analyzed to gather information about the particles that produced it, such as their energy and direction of travel.

Similar threads

I Geometry of Cherenkov radiation
    • Classical Physics
Replies
4
Views
536
I How visible is ionizing radiation?
    • High Energy, Nuclear, Particle Physics
Replies
13
Views
2K
I Why is Cherenkov radiation blue? And what about refractive index?
    • Classical Physics
Replies
3
Views
804
I Speed faster than light speed in a medium
    • High Energy, Nuclear, Particle Physics
Replies
8
Views
1K
B Can alpha radiation make other materials radioactive?
    • High Energy, Nuclear, Particle Physics
Replies
6
Views
1K
I How prone is a photon to interacting with uncharged structureless particles?
    • High Energy, Nuclear, Particle Physics
Replies
8
Views
1K
Can neutrinos cause Cherenkov radiation?
    • High Energy, Nuclear, Particle Physics
Replies
7
Views
3K
I Impossibility of constructing a particle consisting of only neutrons and proton-neutron interaction
    • High Energy, Nuclear, Particle Physics
Replies
6
Views
892
Neutrino's and Cherenkov Radiation
    • High Energy, Nuclear, Particle Physics
Replies
5
Views
3K
I How do you get polarized charged particles?
    • High Energy, Nuclear, Particle Physics
Replies
11
Views
2K

Hot Threads

Recent Insights

Back
Top