A neutrino ( or ) (denoted by the Greek letter ν) is a fermion (an elementary particle with spin of 1/2) that interacts only via the weak interaction and gravity. The neutrino is so named because it is electrically neutral and because its rest mass is so small (-ino) that it was long thought to be zero. The rest mass of the neutrino is much smaller than that of the other known elementary particles excluding massless particles. The weak force has a very short range, the gravitational interaction is extremely weak, and neutrinos do not participate in the strong interaction. Thus, neutrinos typically pass through normal matter unimpeded and undetected.Weak interactions create neutrinos in one of three leptonic flavors: electron neutrinos (νe), muon neutrinos (νμ), or tau neutrinos (ντ), in association with the corresponding charged lepton. Although neutrinos were long believed to be massless, it is now known that there are three discrete neutrino masses with different tiny values, but they do not correspond uniquely to the three flavors. A neutrino created with a specific flavor has an associated specific quantum superposition of all three mass states. As a result, neutrinos oscillate between different flavors in flight. For example, an electron neutrino produced in a beta decay reaction may interact in a distant detector as a muon or tau neutrino. Although only differences between squares of the three mass values are known as of 2019, cosmological observations imply that the sum of the three masses (< 2.14 × 10−37 kg) must be less than one millionth that of the electron mass (9.11 × 10−31 kg).For each neutrino, there also exists a corresponding antiparticle, called an antineutrino, which also has spin of 1/2 and no electric charge. Antineutrinos are distinguished from the neutrinos by having opposite signs of lepton number and right-handed instead of left-handed chirality. To conserve total lepton number (in nuclear beta decay), electron neutrinos only appear together with positrons (anti-electrons) or electron-antineutrinos, whereas electron antineutrinos only appear with electrons or electron neutrinos.Neutrinos are created by various radioactive decays; the following list is not exhaustive, but includes some of those processes:
beta decay of atomic nuclei or hadrons,
natural nuclear reactions such as those that take place in the core of a star
artificial nuclear reactions in nuclear reactors, nuclear bombs, or particle accelerators
during a supernova
during the spin-down of a neutron star
when cosmic rays or accelerated particle beams strike atoms.The majority of neutrinos which are detected about the Earth are from nuclear reactions inside the Sun. At the surface of the Earth, the flux is about 65 billion (6.5×1010) solar neutrinos, per second per square centimeter. Neutrinos can be used for tomography of the interior of the earth.Research is intense in the hunt to elucidate the essential nature of neutrinos, with aspirations of finding:
the three neutrino mass values
the degree of CP violation in the leptonic sector (which may lead to leptogenesis)
evidence of physics which might break the Standard Model of particle physics, such as neutrinoless double beta decay, which would be evidence for violation of lepton number conservation.
I was wondering if anyone could help clarify this problem I am having.
Upon reading a section in a paper, I am a bit stuck as to how this value of the lower bound of the neutrino mass is reached here. I have highlighted the relevant part in the snapshot...
Hey,
Was reading how the CMB is ~2.75 Kelvin, while the Neutrino BG is ~2 Kelvin. Clearly this means that neutrino transparency occurred before photon transparency did in the early evolution of the universe. My question is why? Does is have anything to do with neutron-to-proton decay...
new paper by Kovtun and Zee
http://arxiv.org/abs/hep-ph/0604169
idea of composite neutrino
earlier we discussed Sundance Bilson-Thompson topological preon model incorporated into quantum gravity by Lee Smolin
and described in the online Lecture Series Introduction to Quantum Gravity, Lecture...
I'm looking to analyse data in favour of neutrino oscillations for my masters project. I know John Bahcall has some on his website, but this is for solar neutrino oscillations and takes account of the MSW effect. Does anyone know where any raw data for atmospheric neutrino oscillations (i.e...
I have to make a homework problem about neutrino oscillations, but I already don't know how to answer the first question.
Let \Psi_i, i = 1,2 be two spinor fields, with field equation
\gamma^{\mu}\partial_{\mu}\Psi_i = - \sum_{j=1}^2 M_{ij} \Psi_j
where M_{ij} is a hermitian matrix. Suppose...
Hi,
I have the following question: Neutrinos can be detected by an inverse beta-decay. The probability for an interaction of a neutrino and a proton is 10^(-43). How large should be a detector filled with water in order to let interact one of 1 million neutrinos with a proton? What would be...
I've got a couple options for summer research, and I was wondering what the board's views on the fields of nuclear physics and neutrino physics were. Where do you think these two fields will go in the next twenty years? Will they be funded regardless of the next US administration? Is there...
The core of the collapsing star is initially composed of iron supported by electron degeneracy pressure, since the nuclear fusion of iron doesn't release energy. When the core collapses, the densities and pressures in the core overcome even the electron degeneracy pressure and the iron atoms'...
Hi friends,
I have read that particles like neutrino have zero mass and zero charge.Yet it has the spin value (1/2).How it is possible?It is difficult even to imagine an item of zero mass spinning.Is it right to call an item of zero mass as a particle?If yes,What is a particle ?Can someone...
Boris Kayser at Fermilab put on arXiv as nice summary of the state of the art in Neutrino Physics yesterday. It is here: http://es.arxiv.org/PS_cache/hep-ph/pdf/0506/0506165.pdf
The presentation is more lucid than most.
The paper definitely find that neutrions can change flavor which...
Hi, I have read some texts on the Internet on neutrino detection but I have some things I hope you can clarify..
When using heavy water (D20) for detection, the neutrino will interact with the deuterium nucleus producing a proton and an electron from the neutron. Now I have read that a...
I am in my senior year of undergrad studies and would like to read a research paper on the NEUTRINO MASS. I am hoping for it to be at a level which I can understand. I am taking particle physics right now. Are there any sites that would offer such documents?
James
Neutrino astrophysics fans may find this recent paper interesting:
APS Neutrino Study: Report of the Neutrino Astrophysics and Cosmology Working Group
http://arxiv.org/abs/astro-ph/0412544
I took the liberty of pasting a couple quotes I found provacative
Detection of relic neutrinos...
I have two questions about neutrinos that I haven't been able to figure out:
1. The evidence seems to indicate that neutrinos have rest mass. Since it is invisible to charge and electromagnetic fields and, apparently, gluon fields, how does it interact with matter at all? I think it may have...
the electron, neutrino and positron as well?
Hope I'm asking this at the right place, and that my spelling was ok!
Thanks for any replies!
Linda, Sweden
I was reading a book by Timothy Ferris and he mentioned something about if we could create a neutrino telescope we could see back in time to something like 1 second after the big bang. does anyone know if one of these telescopes could be made and what do you think we would see with them?
Is there anything else that the neutron does other than saveing the conservation laws. i mean there has to be something else the neutron plays a part of in the universe.
As some theory resuly, in p or n, there is a tini wormhole, to pass the tini hole, only by a neutrino. Naturely lower enerty is super.
To freeze p or n self whirlpoor in one direction by strong enough magnetic field. and pole the neutrino by strong laser beam structure. After some neutrino to...
A neutron plus a W particle yield a proton an electron an antineutrino and a W- particle.
The reactants - the neutron and W particle do not have oscillating masses.
One of the products does - the antineutrino.
Shouldn't there be an oscillating mass on both sides of the equation?
This is just a silly idea I had. Probably will never happen but interesting to talk about I think.
If a substance could be developed that easily reacted with neutrinos could it become a revolutionary power source?
First let's see how much power we could derive if we took all the energy...
Introduction to the Neutrino Report
Their was a calculation done about 50 years ago that showed that 1/3 of the neutrino’s from the nuclear reaction of the sun were missing(they measured the neutrino’s from Sun and their were 1/3 less than their should have been from...
Third and final A2 Physics paper tomorrow.
Currently struggling with one of the articles we have been given to study before the exam. It's all about neutrinos. I've been given some questions to try, educated guesses by teachers on what could come up on the exam paper.
"If the Sun is 150 Gm...
Why does the neutrino, which used to be assumed massless, have momentum? I know the answer to this has something to do with special relativity, but I'm not overly familiar with the theory.
Thanks,
Chris
Back in 1960's ,one could frequently hear opinions/claims that neutrino rest mass is 0.Not a very small one ,but exactly=0.Therefore,a nutrino would just like photons propagate at light velocity through the space.
What has changed in a meantime (since decade -two), except better insight to...
On the bottom of http://elasticity2.tripod.com/ I have added two supplements that explain the relationship between e neutrino, electron, positron and u quark. This is up for discussion in
Theory development :Vacuum theory; mass and charge
Hey all, I'm a Theoretical Physics undergrad and so far I've only done one course in QM. Mainly playing with the TISE pushing wavefunctions around.
Anyway after some trolling on here I've gotten to wondering, in a hydrogen atom why doesn't the electron just collapse into the nucleus? The...
I'd appreciate it if I could get a little help on this one, I'm confused about how this is done. I know there are numerous papers out there about how to do this based on the SN1987A event that was detected with KII and IMB. The problem in my textbook asks me to make a rough estimate of the...
can anyone tell me if the, "solar neutrino problem", has been
solved, i ask because, i found a April 2004 paper that "solves"
the problem by linking to Planck scale foams aka LQG.
the thread is "quantum gravity Planck scales" in S and GR.
http://arxiv.org/abs/hep-ph/0404014
Interesting Image of the solar stellar core neutrino flux:
http://antwrp.gsfc.nasa.gov/apod/ap980605.html
This image is of the solar stellar core, only a fraction of the total radial size of Sol.
If the solar stellar core neutrino flux is less than that predicted by the standard stellar...
I saw a series about neutrino research on TV and evrybody talked about 'Geisterteilchen' (ghost parts, literally translated)
As far as I understood there are 2 elementar pieces who change their spin in the same way though they might be at a great distance.
Evry try to measure the spin is...
When the cosmic background radiation first appeared 300,000 years after the Big Bang, was it x-rays and then redshifted over time to microwaves?
And to see what the Universe looked like before 300,000 years after its birth, will we need a neutrino telescope?
i have heard that there exists an anomaly in amount of neutrinos coming from sun. are there any explanations around? how is the presence of Jupiter sized planets near stars have been explained?
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ABSTRACT
This paper concern with neutrino exceeded light speed to come in this world. Its energy transform and its energy explore on the time-space boundary .This paper include a design to catch the neutrino.
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