Neutrinos are light, uncharged leptons. The neutrino tag should be applied to question relating to neutrino properties or interactions involving neutrinos.

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Earth density distribution from shooting neutrinos?

I am interested in possibility of inferring Earth interior structure from gravitational data. As classical calculus problem shows, it is impossible to understand non-uniform density distribution ...
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What type of neutrinos do we detect

There are three types of neutrinos known today. When detecting them, how can we tell which type we are detecting?
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What is the analogous effect of cosmological redshift for particles with mass?

Due to the metric expansion of space, light emitted from earlier times in faraway parts of the universe and travels for a long time to reach us get progressively redshifted, decreasing the energy of ...
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Is neutrino-based communication possible?

Referring to this article, where we see there are three flavors of neutrinos, got me thinking of simple binary-based communication, but more like the UDP protocol where we can live with dropped ...
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How is (anti)neutrinos' spin detected and measured?

Can you give a link or briefly explain how the direction and the value of the spin of a neutrino assessed? In particular, how can we know that in both cases spin is 1/2?
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How can a neutrino disrupt a nucleus?

In a previous answer prof. Strassler's site was cited. In the linked article it is stated that neutrinos can be detected because they can smash atoms: Suppose a neutrino does hit a quark or ...
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Neutrinos have mass. But how much mass?

Can somebody explain to me how much mass neutrinos have. According to my understanding neutrinos oscillate, therefore they should have some mass. If this is right then how much mass do they have?
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Current constraints on lightest neutrino mass?

This paper from 2005 claims that the mass of the lightest neutrino is unconstrained. (see p9) Oscillations are only able to constrain the differences in squares as far as I know, but perhaps ...
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Are Fermi-Dirac-statistics relevant to view the universal system of neutrinos?

Should the energy distribution of neutrinos be affected by Fermi-Dirac statistics? And if so, what would the consequences be? Could this locally cause weak interaction because of the Pauli Exclusion ...
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Is it experimentally verified that the neutrinos are affected by gravity?

If neutrinos (or any other particles) wasn't affected by gravity that would contradict the general theory of relativity. I'm convinced that the postulate of the equivalence between inertial mass and ...
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Radioactive decay as pure radiation of neutrinos and antineutrinos?

Is it possible with radioactive decay as pure radiation of neutrinos and antineutrinos? From a theoretical point of view? I'm not asking for processes since I'm convinced there are no known processes ...
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Do neutrinos have a half-life?

I know that neutrons are stable within the nucleus of an atom but free neutrons have a half-life. I couldn't find any information on neutrino half-lives. Do neutrinos have a half-life? Since ...
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Origin and motivation of various flavor symmetries in the neutrino sector

Flavor symmetries of various kinds (for example, $\mu-\tau$ permutation symmetry, or the scaling symmetry, or $S_3$ symmetry) are sometimes assumed between neutrino flavours to "reproduce" the ...
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The stunning footage of neutral currents, first observation of a neutrino: Knowledge needed

First of all, this question is purely motivated by curiosity. I call upon the community's knowledge on the matter. Following the link below, you can see the image of "A lepton event - a neutrino ...
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What's the significance of neutrino oscillations? [duplicate]

I read some about netrino oscillations and flavour changing between three types of neutrinos. The question is, what is the significance of that observation? So far, we did not expect them to oscillate ...
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1answer
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What is “forward peaking”?

In "Research and Development for a Gadolinium Doped Water Cherenkov Detector" the phrase "forward peaking" is used to describe a signal. This comes up in lots of other contexts too, but I still can't ...
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Free neutrons in the sun's core?

In the standard description of proton-proton fusion, the first step of the interaction proceeds through the unbound diproton $\rm^2He$: $$ \begin{aligned} \rm p + p &\to \rm {}^2He^* \\ \rm ^2He^* ...
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Muon Neutrinos vs Electron neutrinos

I read somewhere that for muon neutrinos, why is the upward measured flux half of what simulation of neutrino production in atmosphere predicts while the downward flux is the same? Whereas for ...
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Is there a numerical calculation for black hole - neutron star merges?

I think it might be even a more frequent event as the black hole merges. It would be similar to the black hole merges in the gravitational wave spectrum, but it could have a very clear neutrino and ...
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What is the smallest amount of neutrinos needed to create a black hole? [duplicate]

Is there some smallest amount of neutrinos needed to create a black hole? Note that this question is not at all the same as the question here If a 1kg mass was accelerated close to the speed of light ...
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What is the property of neutrino? [closed]

If mass of a particle is due to Higgs boson, spin is due to Z boson and translational energy is due to photons, what exactly is the innate property of a neutrino? If none exist, is neutrino truly a ...
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Alternatives to the neutrino in the beta spectrum?

It is well known that the neutrino appeared to explain the power distribution in the beta decay spectrum. (see PSE) What other explanations candidates were available? It is stated that the ...
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Wu experiment and masses of neutrino

Wu experiment have shown that there are only left-handed neutrinos (and right-handed antineutrinos) take part in weak interactions. My question is about the significance of this experiment in a ...
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Why do electrons, according to my textbook, exist forever?

Does that mean that electrons are infinitely stable? The neutrinos of the three leptons are also listed as having a mean lifespan of infinity.
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Are neutrinos weekly interacting particles? [closed]

Occasionally, I read about weekly interacting neutrinos, and although I know this is a typo, I wonder if it happens to be true. Do average neutrinos, as they fly through the universe, really interact ...
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Can the Cosmic Neutrino Background be detected from a lab moving near the speed of light?

If I've understood it correctly, the energy of an object depends on the reference frame, so when you accelerate, the CMB and CNB appear to gain energy (relative to your rest frame). So if you are ...
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Is the $\nu_e$ massive?

Neutrino oscillations imply that the $\nu_\tau$ is more massive than the $\nu_\mu$, and the $\nu_\mu$ is more massive than the $\nu_e$, so it's inferred that the $\nu_\mu$ and $\nu_\tau$ have mass. ...
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Neutrinos born before inflation

What would happen, if there was (hypothetically, for any reason) a very large number of neutrinos+antineutrinos before the inflation period. They probably dont like to annihilate too much. I would ...
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Do electrons oscillate into muons just like electron-neutrinos into muon-neutrinos?

And if not, why? What is the difference to neutrinos oscillations?
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Is it possible that neutrinos or some other sub-atomic particle contributes to radioactive decay?

According to Wikipedia: For most radioactive nuclides, the half-life depends solely on nuclear properties and is essentially a constant. It is not affected by external factors such as ...
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Using the boltzmann equation to find neutrino decoupling temperature

I'm an undergraduate student currently following a particle astrophysics lecture. I was reading some stuff about the neutrinos decoupling before the $e^+ e^-$ annihilations. It's possible to quickly ...
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Can the brain detect the passage of a neutrino?

On a few occasions either in bed or sitting around a fire, with my eyes closed, I rarely but sometimes see a very quick fast flash of white and then, with my eyes still closed, the flash disappears ...
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Why are right hand neutrinos unaffected by all forces except gravity

I'm curious as to something I read on Berkeley's website. Does anyone happen to know why, according to this model,right hand neutrinos are unaffected by all forces except gravity? (Model taken from ...
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1answer
64 views

What are the quantum numbers of Majorana neutrinos?

I have a question about majorana neutrinos. Majorana particles are particles that are their own antiparticle. From this I would argue that they need to have all quantum numbers equal to zero. My ...
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Neutrino mass and the Majorana equation

I can't seem find this on the Internet. What does the Majorana equation predict neutrino masses to be (if they were their own antiparticle), and how? (I have little understanding of spinors, btw...) ...
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Understading triplet Majoron model

In the Higgs triplet Majoron model, the spontaneous breakdown of ungauged lepton number gives rise to two Numbu-Goldstone bosons. But isn’t the SU(2) symmetry also broken? I mean when the neutrak ...
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Would the blue glow of Cherenkov radiation be visible when diffused across ice, such as in the IceCube neutrino experiment?

The blue glow characteristic of Cherenkov radiation is visible emanating from underwater reactors. Is it also visible through ice, at the IceCube neutrino experiment (not that anyone is physically ...
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Why are the neutrino flavour eigenstates and mass eigenstates different?

Why does this happen for neutrinos and not for say, electrons and muons. Is there some way to predict which particles might oscillate amongst their flavour and which won't?
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Why are neutrinos ruled out as a major (or even sole) component of dark matter?

A number of times I have encountered in text-books and articles that neutrinos might contribute only a small fraction to dark matter. The reason has to do with the fact that if all of the dark matter ...
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572 views

Charged current vs. neutral current neutrino interactions

I am doing research related to the detection potential of neutrino detectors and, in looking up the various neutrino interaction channels that exist in each detector, I have found the interactions ...
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Why Majorana phases cannot be removed?

Why is the extra two Majorana phases in the PMNS matrix cannot be removed if neutrinos are Majorana fermions? Or in other words, why are the Majorana phases cannot be absorbed into the redefinition of ...
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What're some criticisms of the paper “Six observations consistent with the electron neutrino being a tachyon with mass: mνe² = −0.11±0.016 eV²”?

Today I read about this paper making the case that neutrinos have imaginary mass and travel faster than light. I want to get excited, but I have no way to know how likely it is that this paper will be ...
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Elastic scaterring of neutrinos - Why does the electron neutrino dominate this channel

Could anyone add more detail to this statement off wikipedia In the elastic scattering interaction, a neutrino collides with an atomic electron and imparts some of its energy to the electron. ...
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Why could the Homestake experiment only detect electron neutrinos

The Homestake experiment measured the incoming electron neutrino flux via $$\nu_{e}+ Cl^{37} \rightarrow Ar^{37} +e^{-}$$ Why does this reaction not apply to the other neutrino flavours? i.e. what ...
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Cosmic rays and neutrinos

I'm reading Gaggero's Cosmic Ray Diffusion in the Galaxy and Diffuse Gamma Emission and he makes the claim, ...the definitive proof of [Cosmic Ray proton acceleration in supernova remnants] would ...
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Is Helicity an intrinsic property of massive Neutrinos?

Hyperphysics states that, unlike an electron, the helicity of a neutrino is invariant because we cannot change to a reference frame where it is different: This and subsequent experiments have ...
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Neutrino decoupling and units

I have a problem that states: In the early Universe, neutrinos can be created and destroyed by the process: \begin{equation} \nu \bar{\nu} \leftrightarrow e^{+}e^{-} \end{equation} The thermally ...
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Why is 0 $\nu \beta\beta$ decay often written with electron emission and not positron?

According to http://www.cobra-experiment.org/double_beta_decay/ I can see that double $\beta$+ decay is possible, but I often find neutrinoless double beta sources with the double $\beta$- decay ...
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Are atoms made of protons, electrons and neutrinos?

If neutrons decay into proton, electron and (anti)neutrino of electron type, then is it safe to say that atoms are protons, electrons and neutrinos?
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Why aren't purely Dirac neutrinos ruled out?

It is common knowledge that in neutrinos can be Dirac particles without any Majorana masses as given a mass matrix, \begin{equation} \left( \begin{array}{cc}\nu _L & \nu _R \end{array} \right) ...