I read those (an many more) articles, do they contain experimental data? I must have missed them.I am asking if there is any concrete experimental data that confirms that it has indeed some spin and that its magnitude is h/4pidavenn said:
Thanks , Dave, I was just looking for some experimental evidence, or at least some indirect confirmation. I know the Standard Model assumes all fermions, leptons have spin 1/2. But suppose (ad absurdum) neutrino has no spin, what happens, what is the problem?davenn said:there probably is, but I haven't found any info in my looking
not sure what else you want ?Dave
alba said:.I am asking if there is any concrete experimental data that confirms that it has indeed some spin and that its magnitude is h/4pi
Why can't spin be added during the process?mfb said:A different spin would lead to different angular distributions of the decaying particles, something measured in the experiments of Wu and Goldhaber, and later much more precisely with particle accelerators.
What I meant is that the spin musn't necesseraly be an intrinsic property. Like in a billiard ball any spin can be generated by the cue or by a collision, the value of the spin +1/2 or -1/2 (or any other value) could be determined only by the process. This would also eliminate the akward assumption of an antineutrino antiparticle of itself. Does the linked experiment rule out this possibility? Ihave not the expertise to reach any conclusion.Vanadium 50 said:If the neutrino were spin-0, it would mean angular momentum is not conserved.
If the neutrino were spin-3/2, [itex]\frac{B(\pi \rightarrow \mu \nu \overline{\nu})}{B(\pi \rightarrow e \nu \overline{\nu})}[/itex] would be some number other than the measured ~12,000.
alba said:What I meant is that the spin musn't necesseraly be an intrinsic property.
What do you mean by "added"?alba said:Why can't spin be added during the process?
Assumption of what? It is possible that neutrinos are their own antiparticles, but they don't have to be - measurements are not precise enough yet to distinguish between those possibilities.alba said:This would also eliminate the akward assumption of an antineutrino antiparticle of itself.
mfb said:I think you just want one neutrino in the decay.
alba said:What I meant is that the spin musn't necesseraly be an intrinsic property.
By the way, have you ever seen a billiard ball "spinning" at half-integer angular momentum?alba said:What I meant is that the spin musn't necesseraly be an intrinsic property. Like in a billiard ball any spin can be generated by the cue or by a collision, the value of the spin +1/2 or -1/2 (or any other value) could be determined only by the process. This would also eliminate the akward assumption of an antineutrino antiparticle of itself. Does the linked experiment rule out this possibility? Ihave
Neutrinos are subatomic particles that have no electric charge and very little mass. They are important to study because they are the most abundant particles in the universe and can provide valuable insights into the fundamental laws of physics.
The spin of a neutrino refers to its intrinsic angular momentum. It is significant because it determines the behavior of neutrinos in various interactions and can provide information about their properties, such as their mass and flavor.
Scientists use a variety of experimental techniques, such as analyzing the polarization of emitted particles, studying the scattering and decays of neutrinos, and observing the effects of magnetic fields on neutrino beams, to measure the spin of neutrinos.
One of the main assumptions is that neutrinos have a definite and well-defined spin, which is not always the case in quantum mechanics. Another assumption is that neutrinos are Dirac particles, meaning that they have distinct antiparticles with opposite spin.
There have been various experimental observations that support the idea of neutrino spin. For example, the observation of neutrino oscillations, or the transformation of one type of neutrino into another, can only be explained by the fact that neutrinos have a non-zero spin and mass.