Question about particle reaction

[Clear Mind]

It's an easy question, let's consider this reaction:
$N+\nu_e \rightarrow e^{-}+P$
Is this reaction possible? If is not, what does violate?

(I think is possible because charge is conserved, baryon, lepton and fermion numbers are conserved. But I'm not totally sure)

 

[dukwon]

Yes, this is charged-current neutrino scattering. It's one of the processes that neutrino detectors look for.

 

[Orodruin]

Yes.

However, note that for free neutrons, it is much more likely that the neutrons will decay naturally unless you have an outrageously high neutrino flux.

 

[Clear Mind]

Thank you all!

It's one of the processes that neutrino detectors look for.

I suppose that the cross section it's really small ...

 

[Orodruin]

Thank you all!

I suppose that the cross section it's really small ...

This is why neutrino detectors are really big ... :)

 

[Clear Mind]

From a few day I've started to study particle physics, so I'm still a little bit confused ... I was wondering:
$N+\nu_e \rightarrow e^{-}+P$
it's a weak interaction, so it should violate c-symmetry, thus:
$\bar{N}+\bar{\nu_e} \rightarrow e^{+}+\bar{P}$
shouldn't be possible ...
I'm a little puzzled :(

 

[dukwon]

It is possible if you make both a charge inversion and a parity operation, since the weak force couples to left-handed fermions and right-handed antifermions.

Usually when we talk about an antiparticle it's the CP-conjugate rather than the C-conjugate.

 

[ChrisVer]

yes it is impossible, because you turned a right-handed neutrino into a right-handed antineutrino ... which doesn't exist [in SM]

 

[dukwon]

yes it is impossible, because you turned a right-handed neutrino into a right-handed antineutrino ... which doesn't exist [in SM]

It's the other way round. Antineutrinos have to be right-handed in the Standard Model.

 

[Clear Mind]

yes it is impossible, because you turned a right-handed neutrino into a right-handed antineutrino ... which doesn't exist [in SM]

Right! i was considering only charge, baryon, lepton and fermion numbers but not the parity :s

 

[ChrisVer]

It's the other way round. Antineutrinos have to be right-handed in the Standard Model.

OMG! indeed! Well I'm always forgetting the a-priori left and right... [except for when I write the doublets]...

 

[mfb]

C and CP violation do not mean the process is completely impossible. It can have a different dependence on the relative angles (P violation), or occur a bit more or less frequent even with an additional P transformation (CP violation), but it is still possible.