Neutrino mass Definition and 31 Threads

Ever since High school I've seen this model of the "particle zoo," including in my recently finished particle physics undergrad course, and I can't seem to find where the mass numbers for the neutrino family is coming from! Sure the model has a less than sign, but from what I understand all...

[This is a reference request.] I'm dissatisfied with the "proofs" I've found so far. E.g., in Kayser's review from 2008, in the paragraph following his eq(1.4), he assumes a propagation amplitude Prop##(\nu_i)## of ##\exp(-im_i \tau_i)##, where "##m_i## is the mass of the ##\nu_i## and...

arXiv: On the most constraining cosmological neutrino mass bounds From neutrino mixing we know that an inverted order (two "heavy" neutrinos, one light neutrino) needs a sum of masses of at least ~0.09 eV, while the normal order (two light, one "heavy") can have a sum as low as ~0.05 eV. The...

I am trying to find a picture of the N-body simulations that shows the LSS. Particularly I am looking for different neutrino masses without the CDM. For instance pictures likes this But with more varying/different neutrino masses. I am looking for articles

In an article its written, $$\Omega_{\nu} = \frac{\rho_{\nu}}{\rho_{crit}}=\frac{\sum m_{i,\nu}n_{i,\nu}}{\rho_{crit}} = \frac{\sum m_{\nu}}{93.14h^2eV}$$ Now I am trying to derive this for myself but I could not. Can someone help me ? So the values are, ##\rho_{crit} = 1.053 75 \times...

In five years also experiment KATRIN will give either the upper bound of electron neutrino mass (0,2 eV) or even the mass of the electron neutrino. https://www.katrin.kit.edu/ My question is, what we can expect from the astronomical and non-astronomical measurements to improve these data? I...

Why is there an assumption that if neutrinos didn't have mass they would move at the speed of light? and how does the fact they oscillate prove they have mass?

This T-shirt I bought at a physics conference displays the following equation. It looks like the Lagrangian of the Standard Model of particle physics but I only recognise lines 1 (electroweak) and 3 (Higgs mechanism). What are lines 2 and 4 and what is/isn't included? eg. are quarks, gluons...

I have just started reading about neutrino physics and recently came across two terms called double seesaw and singular seesaw. Although I’m familiar with other seesaw mechanisms (such as type-I and II) for explaining smallness of neutrino mass. I’m completely at dark about double and singular...

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...

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...

ok so this is a bit of a boring question, so sorry in advance, but for some reason I am struggling with this. I am deriving the seesaw formula. Now I have gone through the derivivate and I get A : ## m_{\nu} = - m_D^T M^{-1} m_D ## Now I have seen other derivations where they get B ...

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...

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...

I understand the basics of neutrino oscillation from the starting point of each neutrino flavour state being a superposition of mass states, or vice versa. However, the introductory texts I've seen never seem to explain what motivated such an idea. What made Pontecorvo think this?

Relic neutrinos decoupled from matter around the time of nucleogenesis so had the same temperature as matter and photons at that time. Photons decoupled much later, after electron/positron annihilation which heated the photons slightly so thereafter neutrino temperature should be (4/11)^(1/3)...

I just came across this paper arguing that the electron neutrino may have negative mass squared: http://arxiv.org/abs/1408.2804 It says it has been accepted for publication. I'm wondering if anyone has seen it and can comment on the paper's arguments.

In reading through all the info that is coming out from today's big announcement, it seems as they still can't peg the mass of the higgs boson as much of their data comes in the form of decay paths that include neutrinos of unknown mass. My question is whether when they peg the exact mass of...

Hi, Quick question. In the SM, why can't we have loop-level interactions that give neutrinos their small masses? (It seems like we must also have Majorana neutrinos)Thanks.

Hi, We know that when we have one flavour of neutrino, it can change into another flavour by neutrino oscillations. However, if we consider a mass eigenstate, then is it true that it can never change into a different mass eigenstate? In other words is a |v_{1}> neutrino forever a |v_{1}>? I...

when beta decay is observed it is noticed that some of the energy and some of the momentum is missing. it is thought that this missing energy and momentum is carried away by a neutrino. the neutrino mass is still unknown. if you know how much momentum (mv) is missing and you know how much...

can the neutrino mass eigenstate couple to the group of SU(2) doublet?if we intentionally not impose any flavor symmetry on it. \left(\begin{array}{c}\nu_{1}\\e\end{array}\right)

I've been reading up on neutrino oscillations and I have come across this issue. I know that oscillations are dependent on the mass squared differences of the mass eigenstates, which is why determining things like the absolute masses of the eigenstates and the hierarchy of the eigenstates is...

In books I find that the Majorana mass term for the neutrinos is given by m_L \nu_L^T C^\dagger \nu where C is Dirac Conjugation operator. How does C look like if I write \nu_L as in terms of its two components \left(\begin{array} (\nu_{L1} \\ \nu_{L2} \end{array} \right)? Is C=...

Wikipedia says that the phenomenon of Neutrino Oscillation implies that the neutrino has a non-zero mass (http://en.wikipedia.org/wiki/Neutrino_oscillation" ). Why is that? Why is it that Neutrino Oscillation can only exist, if neutrinos do have mass?

Hi everyone, I have always been very worried about the possible consequences of neutrino masses. I just came accros a paper which I thought I would share with you. First, the reference : Neutrino mass and mixing implied by underground deficit of low energy muon-neutrino events John G...

I tried and I got a ridiculous large number for the neutrino mass. I basically used E=\gamma m c and then, for 10 MeV neutrinos, time taken is t + 10 seconds to reach Earth, for 50 MeV neutrinos, time taken is t seconds. Speed = \frac{100 000}{(t+10)} for 10 MeV and Speed = \frac{100 000}{t}...

so does the Higg field give the neutrino mass, and can neutrino velocity change? how close to c is neutrino velocity?

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...

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

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...