Neutrino oscillations: Recent results and future directions

Advances in High Energy Physics, 2014

In the last decades, a very important breakthrough has been brought about in the elementary particle physics by the discovery of the phenomenon of the neutrino oscillations, which has shown neutrino properties beyond the Standard Model. But a full understanding of the various aspects of the neutrino oscillations is far to be achieved. In this paper the theoretical background of the neutrino oscillation phenomenon is described, referring in particular to the paradigmatic models. Then the various techniques and detectors which studied neutrinos from different sources are discussed, starting from the pioneering ones up to the detectors still in operation and to those in preparation. The physics results are finally presented adopting the same research path which has been crossed by this long saga. The problems not yet fixed in this field are discussed, together with the perspectives of their solutions in the near future.

Neutrino Physics in recent times has been going through a revolutionary period. Measurements of neutrinos coming from the sun or produced by cosmic rays in the Earth's atmosphere have revealed that neutrinos "oscillate", that is they change their flavor periodically with time. The observation of this phenomenon allows to obtain precious information on the neutrino masses and their mixing, shedding information about the "flavor problem", that is the origin of the fermion families and of the masses and mixing of quarks and leptons. In these lectures we introduce the subject and review these recent developments .

Progress in Particle and Nuclear Physics, 1999

This review is focused on neutrino mixing and neutrino oscillations in the light of the recent experimental developments. After discussing possible types of neutrino mixing for Dirac and Majorana neutrinos and considering in detail the phenomenology of neutrino oscillations in vacuum and matter, we review all existing evidence and indications in favour of neutrino oscillations that have been obtained in the atmospheric, solar and LSND experiments. We present the results of the analyses of the neutrino oscillation data in the framework of mixing of three and four massive neutrinos and investigate possibilities to test the different neutrino mass and mixing schemes obtained in this way. We also discuss briefly future neutrino oscillation experiments. 7 Conclusions 88 A Properties of Majorana neutrinos and fields 92 1 Notice that in the Goldhaber et al. experiment the helicity of the electron neutrino was measured. The helicity of the muon neutrino was measured in several experiments (for the references see the review of V.L. Telegdi [13]). The best accuracy in the measurement of the muon neutrino was achieved in the experiment by Grénacs et al. [14].

Pramana, 2006

We discuss effects of new physics (NP) in neutrino oscillation experiments. Such effects can modify a production neutrino flux, a detection cross-section and a matter transition. As a result, the NP effects change neutrino oscillations both in vacuum and in matter. A relation between the small effects of NP and the oscillation parameters is discussed. It is shown for which parameters the NP effects are suppressed and when they are potentially large. Oscillations of non-unitary mixed neutrinos are presented in more details.

Nuclear Physics B - Proceedings Supplements, 2005

I discuss the theoretical background and the status of neutrino oscillation parameters from the current worlds' global data sample and latest flux calculations. I give their allowed ranges, best fit values and discuss the small parameters α ≡ ∆m 2 sol /∆m 2 atm and sin 2 θ13, which characterize CP violation in neutrino oscillations. I mention the significance of ββ0ν (neutrinoless double beta decay) and current expectations in view of oscillation results.

I discuss, in a semi-pedagogical way, our current understanding of neutrino physics. I present a brief history of how the neutrino came to be "invented" and observed, and discuss the evidence that led to the recent discovery that neutrinos change flavor. I then spend some time presenting mass-induced neutrino flavor change (neutrino oscillation), and how it pieces all the neutrino puzzles except for the LSND anomaly, which is also briefly discussed. I conclude by highlighting the importance of determining the nature of the neutrinos, i.e., are they Dirac or Majorana fermions.

1998

2021

Neutrinos are one of the most elusive of the Standard Model particles known to physicists today. Despite the fact that crucial characteristics of these leptons remain largely a mystery, studying them can hold the key to fundamental insights for the field of particle physics and for our understanding of the universe as a whole. In order to learn why there is so much discussion within the physics community about these mysterious particles, its important to start at the beginning and connect one of their most important characteristics that of oscillations between their types with the subject of quantum mechanics. In fact, to engage with the subject of neutrino physics in general, beyond the surface-level qualitative approach, requires the quantum mechanical framework based heavily in linear algebra. Therefore, this paper will give an introduction to neutrino physics, specifically to their oscillations, through connecting the quantum mechanical formalism to current research within this ...

Phys Rev D, 2009

The CP asymmetry in neutrino oscillations, assuming new physics at production and/or detection processes, is analyzed. We compute this CP asymmetry using the standard quantum field theory within a general new physics scenario that may generate new sources of CP and flavor violation. Well known results for the CP asymmetry are reproduced in the case of V-A operators, and additional contributions from new physics operators are derived. We apply this formalism to SUSY extensions of the Standard Model where the contributions from new operators could produce a CP asymmetry observable in the next generation of neutrino experiments.

Acta Physica Polonica Series B, 2001

Neutrino flavors, light and heavy, are discussed in their interdependence within the minimal unifying gauge group of SO10. The general situation which excludes the existence of an exact symmetry from which exactly vanishing light neutrino masses would follow is discussed. Subtle and simple consequences for ``low--low'' oscillation phenomena are presented in a general framework.

Journal of Physics: Conference Series, 2010

I briefly summarize neutrino oscillation results and discuss their robustness. I mention recent attempts to understand the pattern of neutrino mixing within various seesaw mechanisms, with or without supersymmetry and/or flavor symmetries. I also mention the possibility of intrinsic supersymmetric neutrino masses in the context of broken R parity models, showing how this leads to clear tests at the LHC.

Particles and the Universe Proceedings of the Eighteenth Lake Louise Winter Institute, 2004

This pedagogical overview will cover the current status of neutrino physics from an experimentalist's point of view, focusing primarily on oscillation studies. The evidence for neutrino oscillations will be presented, along with the prospects for further refinement of observations in each of the indicated regions of two-flavor oscillation parameter space. The next steps in oscillation physics will then be covered (under the assumption of three-flavor mixing): the quest for θ 13 , mass hierarchy and, eventually, leptonic CP violation. Prospects for non-oscillation aspects of neutrino physics, such as kinematic tests for absolute neutrino mass and double beta decay searches, will also be discussed briefly.

Physics Letters B, 1987

We examine in detail the possibility that the low rates observed in the chlorine solar neutrino experiment are due to vacuum oscillations between just two neutrino species-a possibility which remains viable over a finite mass range. We calculate the expected signals, seasonal variations, and the effects of time-averaging for both chlorine and gallium based solar neutrino detectors. These provide unique signals for such oscillations, and thus also allow them to be distinguished from the recently proposed resonant neutrino conversion process, as well as from other possible causes of the observed suppression. Finally we display several striking signatures of oscillations relevant to future experiments which may be sensitive to the incident neutrino energy spectrum.

Eprint Arxiv Hep Ph 0609203, 2006

After briefly reviewing how the symmetries of the Standard Model (SM) are affected by neutrino masses and mixings, I discuss how these parameters may arise from GUTs and how patterns in the neutrino sector may reflect some underlying family symmetry. Leptogenesis provides a nice example of how different physical phenomena may be connected to the same neutrino window of physics beyond the SM. I end with some comments on the LSND signal and briefly discuss the idea that neutrinos have environment dependent masses.

Springer Tracts in Modern Physics, 2000

A review of the problem of neutrino mass, mixing and oscillations is given. Possible phenomenological schemes of neutrino mixing are discussed. The most important consequences of neutrino mixing-neutrino oscillations are considered in some details. The data of atmospheric, solar and LSND experiments are discussed. The results of phenomenological analyses of the data under the assumption of the mixing of three and four massive neutrinos are shortly presented.