Neutrinos Definition and 329 Threads

I was thinking about the properties of dark matter - how it doesn't seem to interact with any of the forces of the universe except gravity and I was thinking about how neutrinos also don't have any charge and they don't interact with any other forces except the weak force and gravity. I thought...

http://arxiv.org/pdf/1408.2804v7.pdfDoes the data cited in this paper truly lead to the conclusion presented? Please note that I am uneducated and do not understand the details of this paper, but it seems to me that tachyons are possible provided they don't have a real rest mass. I'd like to...

How do we know that out of 100 percent, 4.96% is Matter, 0.42% is Neutrinos, approx 25% Dark matter and rest 70% is dark energy. How do we know about these percentages if we don't know how large the universe is? Or are these calculations based on the spaces of the VISIBLE universe? Are Dark...

I've seen a few articles that describe neutrino interactions creating anti-particles and that those neutrinos are originating from deep space nuclear reactions. Could neutrinos from a fusion reactor be harvested/used to generate anti-hydrogen? Maybe by circulating protons around a fusion reactor.

I am puzzled by the mechanism that enables neutrinos to be able to pass though many light years of lead without interacting with anything. I understand that they do not feel the strong force and that the weak force is slow to respond, but to travel straight though a 100 light year thick slab of...

that can be detected.

Hi everyone. I think for grad school I want to do work on neutrinos. Anyone know of any good and up and coming schools with good faculty working on these experiments? My application should be good, but not great with great grades/research but very average GRE and PGRE scores.

I am reading Mohapatra's book: "Massive Neutrinos in Physics and Astrophysics". At the beginning of chapter 7, it is sought expressions where the right neutrino was considered in the Electroweak Standard Model. Everything was fine until I found the expression...

I am reading Mohapatra's book: "Massive Neutrinos in Physics and Astrophysics". At the beginning of chapter 7, it is sought expressions where the right neutrino was considered in the Electroweak Standard Model. Everything was fine until I found the expression...

Homework Statement I need some help understanding the following problem: A distant, advanced civilization wishes to make contact with us using neutrinos rather than photons as the transmitting medium to avoid problems of obscuration along the line of sight. Suppose they use an \bar{\nu_e}...

Hello everybody, I am a first year physics student and I have a question about neutrinos and antineutrinos. In a beta minus decay we will get an antineutrino, so I assume that Earth 'produces' more antineutrinos. Does it? However from a beta plus we get neutrinos and positrons. So does...

Could anybody explain why neutrinos have only ever been observed to be left-handed and antineutrinos right-handed? If neutrinos travel slower than light and have mass (albeit very small), as shown by neutrino oscillation experiments, why can neutrinos not change their handedness?

Hello, I am opening this thread so as to discuss if possible what you believe is the science case of building a neutrino telescope. Being a fanatic in the field , I would like to hear opinions from whoever wants to say about whether it is important to build such a detector and why. Thank you!

In β+ decay a proton releases a positron and an electron neutrino causing the proton to change into a neutron to help balance the nucleus. I am studying advanced PET imaging and trying find a better understanding of the positrons other half. Does it just go on being a normal electron.

Weinberg's dark matter idea re "fractional cosmic neutrinos" http://arxiv.org/pdf/1305.1971v1.pdf http://arxiv.org/abs/1305.1971 Goldstone Bosons as Fractional Cosmic Neutrinos Steven Weinberg (Submitted on 8 May 2013) It is suggested that Goldstone bosons may be masquerading as fractional...

I was reading in my QM book that neutrinos are "essentially left handedly polarized." (Townsend on Page 119) If neutrinos can be polarized, what is oscillating? Do other particles with mass exhibit polarization?

Do you think it would be possible to use a beam of neutrinos to probe the structure of atomic nuclei? Since they do not interact electronically, they would be useful to study the structure of both neutrons and protons, either through gravitational deflection or weak interactions. Could this...

1. Problem "Estimate the flux of neutrinos passing through your body per second if the present energy density of neutrinos from the Big Bang is 0.2 MeV/m3. Assume that you are a standard size covering 0.01 m2". Homework Equations nv = Uv(T) / <Ev> The Attempt at a Solution I've assumed that...

Hello, I was wondering if there is any evidence on how (free/not within nucleus) neutron/neutron interactions work. I know there is QCD which states they attract (but maybe only in a nucleus?), but that's theory - has this been experimentally proven at all ? I'm only interested in the free...

If I reach the speed of light which is 300 00 km/s the time will stop! and if I travel faster then light i'll travel to the past (Please Correct me if I'm wrong) I read that the Neutrino is faster then photon (light) so how can be this possible ?! Because if it is really faster than light that...

are the supposed superluminal neutrinos at gran sasso now considered 'pseudoscience'?

EDIT: I apologize for not noticing this earlier, but I realize this should be in the HW/Coursework section of the forum. If possible, would someone be able to move it over for me? Again, sorry for my error and any trouble/confusion. I would like some help calculating the flux of neutrinos...

Hey, I'm a high school student from Europe and my final paper is on Neutrino oscillations. I practiced some basic quantum states(qbit), but i find it much harder for this neutrino problem. I translated it in hope that some of you could give me some pointers. I left some parts of the...

If I'm correct, Cherenkov radiation is caused when particle moves faster than light in a certain medium. Can neutrinos, say, traveling through water, cause Cherenkov radiation then? Or is there a property of neutrinos which prevents that?

I've always understood that the "formula" for the Standard Model is SU(3) × SU(2) × U(1). Since the discovery of the Higgs boson, and observations of neutrino flavor oscillations, has that formula been revised, or is it still the same?

In the traditional Standard Model, Why right handed quarks can have mass And there can't be any right handed neutrino? Wikipedia says that it damages renormalizability, but why does that not happen with the corresponding quarks? In other words, why did you invent the see saw mechanism for...

what are standards model limits on decay of K0, Do, B0 meson into a pair of neutrino and anti neutrino. I know that these highly suppressed due to involve FCNC. but if someone can tell me about theoretical limits on these reactions.

The initial flux of neutrinos from a supernova is mostly radial (say we are far from where they are produced but also far below the top of the dying star)? As the neutrinos help blow the top off the star do the density variations of the outer portions of the star act like a variable index of...

problem regarding determining mass of neutrino (urgent) 1. Homework Statement [/b] It is found that the speed v of the neutrinos with 10 MeV of total energy is (1- v/c) < 2x10^(-9) Estimate the mass of the neutrinos in terms of eV, and determine whether the value you find is an upper or lower...

I'm currently reading a cosmology book, the book is 4 years old. I am looking for more recent articles and developments on the subject. This is in the nature of supportive study material.

I read that matter-antimatter annihilation is not as useful as we thought because a large amount of energy is carried away by neutrinos. So, how much is this energy ? What is the percentage of the lost energy to the energy calculated from E=mc^2 ?

Marcus suggested that the nuMSM deserves its own thread and I agree. The nuMSM is the context in which the Shaposhnikov-Wetterich prediction of the Higgs mass was made. (PF thread.) A search on "nuMSM" at InspireHEP turns up 29 papers, a lot of them about cosmology. Shaposhnikov in...

Hi, I am writing my (undergraduate) research thesis on accelerator/particle/neutrino physics. I'm planning on writing about the history of this field (HEP) and what such research has tried to accomplish. Currently, I'm looking for some books to read up on the history and such of HEP...

I've read that the experimental results of Z-Boson resonance confirm the theoretical expectations that there are 3-types of Neutrinos, not 2 or 4. How are these theoretical expectations calculated? I.e. how does the number of neutrino varieties affect Z-boson resonance? Thank you

Hello, In experiments such as KamLAND, it is expected to measure neutrinos emitted by Japan's nuclear reactors. Such experiments were built to find evidence for neutrino oscillation. Is there anyone who knows how one can make the difference between the neutrinos from nuclear reactors and...

Hi everyone, This is my first post. Years ago I read in a science magazine that (at least according to a certain theory) every shell electron would be accompanied by one (or was it two?) virtual neutrino(s). At least that's my recollection of what I read. I know it sounds a little crazy. I...

Hi, I recently attended several lectures on the topic of neutrino astrophysics. I wanted to verify some of the fact that I gleaned for them, specifically about the Dirac vs Majorana nature of neutrinos. 1) The most basic fact first. If a neutrino is Dirac in nature, then it has 3 flavors...

When the Z boson is around can a neutrino interact with a particle other than an electron? And how does the neutrino find the electron if the neutrino is neutral and does not interact electromagnetically?

What's the difference between a neutrino and a Muon? Will a neutrino induce fusion the same as a muon? Does muon induced fusion take place in the sun? Any help is greatly appreciated.

[SIZE="4"]Definition/Summary There are three masses of neutrino (they are unknown, but the differences of their squares is known approximately). There are three flavours of neutrino: electron- muon- and tau-, and a neutrino when it is created must be one of those three flavours. Each...

A charged lepton can absorb a W+ boson and be converted into a neutrino, and visa versa. The neutrino has such small rest mass, how can it produce these large particles/be produced by them?

Hi all! I am not sure how to prove mathematically that the expression for the probability that a neutrino originally of flavor α will later be observed as having flavor β P_{α \rightarrow β}=\left|<\nu_{\beta}|\nu_{\alpha}(t)>\right|^2=\left|\sum_{i}U_{β i}^*U_{α i}e^{-iE_it}\right|^2 (1) can...

How can someone think of the neutrinos as non relativistic? OK I understand for example that the neutrino temperature is very small even compared to their masses... but at the same time I find it non trivial to think of very light particles with energies: E≥1eV non-relativistic... How can the...

I'm stucked in a passage of Particle Physics (Martin B., Shaw G.) in page 41 regarding neutrino oscillations. Having defined E_i and E_j as the energies of the eigenstates \nu_i and \nu_j, we have: E_i - E_j = \sqrt{m^2_i - p^2} - \sqrt{m^2_j - p^2} \approx \frac{m^2_i - m^2_j}{2p} It...

The arrow for the electron antineutrino is pointing down which is against time, why is that?

Sorry if this is a trivial question; I don't know very much about particle physics.

This article on Majorana particles: http://news.yahoo.com/hunt-source-matter-continues-130052152.html If neutrinos are their own antimatter partners, it could help explain a fundamental mystery of the universe: Why matter exists at all. and If the predictions of the Standard Model —...

Greetings. I thought about how/ why light propagates slower trough matter than vacuum. Generally it is excepted that it happens because photons are absorbed and then emitted by the atoms and it kinda makes sense. But I see other possibilities. I propose and experiment: How about shining...

According to the the definition of anti-particles, they are particles with same mass but opposite charge. Neutrinos by definition have no charge. So, how can it have an anti-particle?

Hi all! This question concerns flavour changing oscillations. Let's narrow it down to the neutrino case, where we have additionally the violation of lepton numbers. So electron and muon neutrinos naturally follow the relativistic Dirac equation: (p\!\!\!/ + m_e ) \nu_e = 0 and (p\!\!\!/ +...