Neutrino Definition and 379 Threads

Sometimes experimental or observational evidence from credible physicists points to new physics and then turns out to be wrong due to statistical flukes, experimental error or a theoretical analysis mistake. What cases of this happening do you find most notable, what showed that the hints were...

I am having a question in mind that why π+ decays to muon and muonic neutrino ,why no electron and electronic neutrino?

Background The Standard Model conserves baryon number, which is equal to (quarks divided by three) minus (anti-quarks divided by three) and lepton number, which is equal to leptons minus antileptons, separately, except in sphaleron processes which conserve B-L, but not B or L separately. There...

i'm wondering about the differences in oscillations between a photon and neutrino, does a neutrino have a wider probability range (or a greater amplitude for a possible location than does a photon) how do the probability ranges for a photon and a neutrino compare when not looking at wavelength...

Wikipedia only tells neutrino spin 1/2, but no tell parity sign: positive or negative?

Neutrino is one of the few things that belong to mainstream beyond standard model stuff. I was reading the October 2017 Scientific American article "Neutrino Puzzle" and I have some questions about the following: https://www.scientificamerican.com/article/the-neutrino-puzzle/ "THE ORIGIN OF...

Homework Statement Mass of neutrino = 0 Mass of proton/neutron = 1 GeV Mass of tau = 2 GeV Homework Equations Energy of neutrino in lab = e Energy of neutrino in CM = e0 The Attempt at a Solution In the centre of mass frame, we will take the momentum of the neutron to be e0/c, c = speed of...

Hi, Assuming an average Neutrino mass of 2.0 Electron volts how much mass will a black hole with an event horizon the size of the one at the center of our galaxy accrete in a year? I've seen estimates of how many Neutrinos pass through our bodies each second and it seems like the mas would...

If we have a beta decay where a solar neutrino is produced: a proton converts into a neutron ,emitting a W. the W decays into an anti electron and a neutrino. So in the end of the chain we have a neutrino that will travel through space and oscillate. Neutrino Oscillation happens because of...

Last night I was watching the latest Alien: Covenant movie, where the crew and colonist are brought out of cryosleep to repair damages to the ship caused by a "neutrino blast". This didn't sit well with me, so I did some searching and thought I'd share what I found: Lethal Neutrinos...

Would neutrinos emitted in the distant and early universe be slowed enough to become thermal neutrinos? Could these be detected?

" But in a study published today in Science, researchers working at Oak Ridge National Laboratory (ORNL) detected never-before-seen neutrino interactions using a detector the size of a fire extinguisher. " From...

I am researcher in computational condensed matter physics. Now, I want to start research on neutrino physics using simulation. Please anybody guide me how to start: I mean which software to use and from where to get experimental data and then simulate. Thank you,

is there a reason that Deep Underground Neutrino Experiment which uses 70, 000 tons of liquid Argon doesn't also do double duty work as a proton decay experiment? Argon has plenty of protons and 70, 0000 tons is a lot of material to work with it costs several billion dollars so why not use...

Neutrinos were flavor eigenstates at the time of their decoupling from baryonic matter. Since they were not pure mass eigenstates, how do you take this fact into account if you try to study how they evolved as the universe expanded? Could we determine if the heaviest neutrino could be non...

In trying to understand the Neutrino where it has mass and its chirality is the same as its helicity, I have always had trouble visualizing a particle. I recently ran into this particle. I believe the "the chirality is the same as helicity" as in one direction it would feed things through the...

Sun produces neutrinos by sundry reactions: p+p→d+e++νe - called "pp" p+p+e→d+νe - called "pep" 3He+p→α+e++νe - called "hep" 3He+p+e→α+νe - never mentioned. What should it be called? "Heep"? Now, heep neutrinos should form a sharp line at a quite high energy. What is the intensity of heep line...

Homework Statement A tau neutrino with energy 1GeV interacts with a stationary neutron. Can the neutrino be detected via a charged current interaction? Take the mass of tau to be 1784MeV/c##^2##, 105MeV/c##^2## for the muon and 939MeV/##c^2## for the neutron. Homework EquationsThe Attempt at...

Homework Statement A free neutron is unstable and decays into proton electron and an anti neutrino. The rest masses of these particles are ##m_n = 939.6 MeV, m_p = 938.3 MeV m_e = 0.51 MeV ##and ##m_{\nu} = 0 ## so that the change in the total rest mass in the decay is 0.79 MeV. If in a...

Hello Just wondering what the difference is between resonant and non-resonant neutrino oscillations. Are resonant neutrino oscillations called Mikheyev-Smirnov-Wolfenstein? Thank you

Hello, I was just wondering when is a right handed neutrino a heavy neutral lepton? I know that RH neutrinos show up in a number of extension to the standard model, for example the neutrino minimal standard model (vMSM) and Left-right symmetric extensions. Ive heard them being referred to as...

Hello, So I am aware that neutrino masses, Baryogengesis/Baryon Asymmetry, and Dark matter cannot be explained by the standard model. However each can be explained by right handed neutrinos. I know that right handed neutrinos show up in many extensions to the standard model, e.g. vMSM (where...

Hello Just wondering, would neutrino oscillations occur is the three standard model neutrinos were the same mass? or are different masses needed in order to have different phases differences, as the phases differences are why the oscillations occur?Also why do neutrino oscillations prove that...

Homework Statement What is the kinetic energy given to the proton in the decay of a neutron when: a) The electron has negligibly small kinetic energy b) The neutrino has negligibly small kinetic energy Homework Equations Q = (mn - mp - me - mv ) c2 = .782MeV Where T is kinetic energy, and...

Hi all, I'm studying ## \mu \to e~ \gamma ## decay from cheng & Lie' book " gauge theory of elementary particles ". In Equation (13.84), he wrote the neutrino propagator ## \sum_i \Big ( \frac{U^{*}_{ei} U_{\mu i}}{(p+k)^2-m_i^2} \Big), ## (where the sum taken over neutrinos flavors) in the...

Homework Statement A charged π meson (rest mass = 273me) decays into a neutrino (zero rest mass) and a μ meson (rest mass = 207me). Find the kinetic energies of the neutrino and the mu meson. Homework Equations E = moγc2 K = mo(γ-1)c2 v = pc2/E p = moγv The Attempt at a Solution In the rest...

Hi, I would like to understand what is the MΔ which appears in the neutrino mass mechanism with Type-II seesaw. It seems to be the Higgs triplet mass. But I do not understand what is (physically) the masse of this triplet when we define it with 3 components : Δ=(Δ++,Δ+,Δ°). It is different from...

This question just occurred to me recently. Assuming the different neutrinos (electron, muon, tau) do not have the same mass, then if their energy is very low, such that they are moving non-relativistically, an oscillation must substantially change the velocity (to conserve momentum). It seems...

IK Pegasi B is considered the white dwarf most likely to supernova in our galactic neighborhood, although some professors (eg: Neil F. Cumins of Maine) thinks it might nova instead. (I agree with Professor Cumins) Questions: At about 150 light years distant would this faint star become...

Question: Draw the lowest-order Feynman diagrams for the e+e- --> W+W-process The answer gives three diagrams. I understand the first two, but the third makes no sense to me. Here it is: So this is a t-channel Feynman diagram. As far as I can tell regarding how these types of Feynman diagrams...

Hello everyone! I've a question regarding the neutrino masses. When neutrinos interact they must do so in a specific flavour (e.g. e, μ,τ) and if we go to find out what their flavour is at the interaction we get a specific answer. However, it is not clear to me what we would find out if we...

Now my understanding of neutrino detectors is that there are two common fluids used in the detectors, either Tetrachloroethylene (C2Cl4) aka "dry-cleaning fluid", and heavy water (D20). Why were these substances chosen specifically? Is there something about the elements within these substances...

I am completely unschooled here, so go a bit easy, if you would. My question(s) involves the actual mechanics of the T2K neutrino/antineutrino experiment that was written up here on Aug. 8. I have a hard time understanding the process described here: "To explore the (anti)neutrino flavour...

here's a link https://www.sciencedaily.com/releases/2016/08/160808091101.htm yet another null result for BSM physics so just in 2016 ... 750 gev diphoton null lux and panda x null susy lhc null 13 tev @ 12.9 fb-1 (consistent with previous 8 tev 20 fb-1 null) sterile neutrino null so what are...

Presentation at ICHEP Report at university website The main plot is on slide 18: ##\delta_{CP}## seems to be somewhere around -2, with 0 appearing unlikely. In other words, muon neutrinos oscillate more likely to electron neutrinos than anti-muon neutrinos oscillate to anti-electron neutrinos...

"9σ" in quotation marks as it seems to include the statistical uncertainty only. Article at physicsworld.com The result was shown at the XXVII International Conference on Neutrino Physics and Astrophysics, the slides don't seem to be available and the abstract is not very helpful. RENO...

Is there any experimental evidence that neutrino spin is equal to the electron spin ( I think h/4pi, right?) If it is just an assumed intrinsic property,can you explain on what grounds it is assumed as such, is it juas a matter of parity?

Was wondering if anyone could give me some stats about the University of Hawaii. I'm tentatively looking at them for particle astrophysics or neutrino physics. Anyone know what the acceptance rate is/how hard it is to get in? Any reviews of the school? Should ranking concern me? They seem to do...

Homework Statement Stopped pions provide a useful mono-energetic source of neutrinos. For a pion at rest, calculate the energy of the neutrino in the decay $$\pi^+\rightarrow \mu^++\nu_{\mu}$$ You do not need to consider the subsequent decay of the ##\mu^+## and you can assume that the...

Hi, I'm a physics 2nd yr undergraduate and know some quantum physics, but I haven't been formally introduced to particle physics or QFT yet. What all do I need to learn before I start reading Giunti and Kim's Fundamentals of Neutrino Physics and Astrophysics? And which books should I refer for...

I was listening to a podcast about the solar neutrino problem, and they discussed how we have deduced that neutrinos are not massless due to the fact that they interact with other particles (even if this interaction occurs rarely). I paraphrase: "a particle traveling at the speed of light is...

Disclaimer: I am a novice. I am wondering if anyone knows if there has been any improvement in detecting any of the three types of neutrinos? I would also be interested in hearing any theories as how we can improve detection? I guess, since I did my research I'm more interested in picking...

What percentage of the total mass of the universe ( byaronic + dark matter and dark energy) is contributed by the neutrino..?? Maybe by relic neutrinos...most of the time I find 340 relic neutrinos per cm3 in website ...should I take account for the neutrinos produced by all the burning...

Hello, I have a simple question. Has the discovery that some neutrinos change their flavor posed any issues with conservation of energy?! How has this been solved?! Thank you.

I am wondering... And I may be wrong but please correct me... In general we have some constraints on the masses of the 3 flavored neutrinos m_{\nu_e}, m_{\nu_\mu} , m_{\nu_\tau} and so there must be some constrain on the values of the 3 neutrino masses m_1, m_2, m_3. Am I right? Also the...

Hello Could antineutrino anomalies be explained by Pandemonium effect? http://physicsworld.com/cws/article/news/2016/feb/18/chinese-lab-confirms-antineutrino-anomalies About Pandemonium effect: https://en.wikipedia.org/wiki/Pandemonium_effect Thank you in advance :) Greetings

When I first heard about the OPERA apparent superluminal results on the measurement of neutrinos speed, I tried to locate an explanation using all the possible relativistic effects. All were too small to account for a difference of 18 meters of virtual distance among photons and neutrinos. Then...

back ground http://arxiv.org/abs/0912.0208 Asymptotic safety of gravity and the Higgs boson mass Mikhail Shaposhnikov, Christof Wetterich (Submitted on 1 Dec 2009 (v1), last revised 12 Jan 2010 (this version, v2)) There are indications that gravity is asymptotically safe. The Standard Model...

it's commonly stated that the standard model has no dark matter candidate. axions and/or sterile neutrions are well motivated extensions of the standard model. if experiments show they exist and are a part of dark matter, would this still be within the framework of the standard model, or is it...

Homework Statement Suppose that two neutrinos are created in the sun - call the states |{ \nu_1}\rangle and |{ \nu_2}\rangle . (Among many other things) I am asked to show that once the neutrinos have propigated a distance x after a time t, the states satisfy: |{ \nu_1}(x,t)\rangle =...