scholarly journals NEUTRALINO INDUCED MAJORANA NEUTRINO TRANSITION MAGNETIC MOMENTS

2009 ◽  
Vol 18 (04) ◽  
pp. 1094-1098 ◽  
Author(s):  
MAREK GÓŹDŹ ◽  
WIESŁAW A. KAMIŃSKI
Keyword(s):  
Magnetic Moment ◽  
Magnetic Moments ◽  
Majorana Neutrino ◽  
Neutrino Magnetic Moment ◽  
Order Of Magnitude

We calculate the effect of neutrino-neutralino mixing on the neutrino magnetic moment and compare it with the contribution of pure particle-sparticle loop. We have found that the dominated mechanism is still the bare loop, and that the bilinear insertions on the external neutrino lines contribute at least one order of magnitude weaker.

scholarly journals MAJORANA NEUTRINO MAGNETIC MOMENTS

2006 ◽  
Vol 15 (02) ◽  
pp. 441-445 ◽  
Author(s):  
MAREK GÓŹDŹ ◽  
WIESŁAW A. KAMIŃSKI ◽  
FEDOR ŠIMKOVIC
Keyword(s):  
Magnetic Moment ◽  
Magnetic Moments ◽  
Majorana Neutrino ◽  
Order Of Magnitude

The presence of trilinear R-parity violating interactions in the MSSM lagrangian leads to existence of quark–squark and lepton–slepton loops which generate mass of the neutrino. By introducing interaction with an external photon the magnetic moment is obtained. We derive bounds on that quantity being around one order of magnitude stronger than those present in the literature.

scholarly journals Origin of the Low Magnetic Moment in Fe2AlTi: An Ab Initio Study

Materials ◽  
2018 ◽  
Vol 11 (9) ◽  
pp. 1732 ◽  
Author(s):  
Martin Friák ◽  
Anton Slávik ◽  
Ivana Miháliková ◽  
David Holec ◽  
Monika Všianská ◽  
...  
Keyword(s):  
Ab Initio ◽  
Magnetic Moment ◽  
Energy Surface ◽  
Magnetic Moments ◽  
Local Magnetic Moment ◽  
Spin Configuration ◽  
Spin Effects ◽  
Order Of Magnitude ◽  
Huge Impact ◽  
Insight Into

The intermetallic compound Fe 2 AlTi (alternatively Fe 2 TiAl) is an important phase in the ternary Fe-Al-Ti phase diagram. Previous theoretical studies showed a large discrepancy of approximately an order of magnitude between the ab initio computed magnetic moments and the experimentally measured ones. To unravel the source of this discrepancy, we analyze how various mechanisms present in realistic materials such as residual strain effects or deviations from stoichiometry affect magnetism. Since in spin-unconstrained calculations the system always evolves to the spin configuration which represents a local or global minimum in the total energy surface, finite temperature spin effects are not well described. We therefore turn the investigation around and use constrained spin calculations, fixing the global magnetic moment. This approach provides direct insight into local and global energy minima (reflecting metastable and stable spin phases) as well as the curvature of the energy surface, which correlates with the magnetic entropy and thus the magnetic configuration space accessible at finite temperatures. Based on this approach, we show that deviations from stoichiometry have a huge impact on the local magnetic moment and can explain the experimentally observed low magnetic moments.

scholarly journals HOW MAGNETIC IS THE NEUTRINO?

2007 ◽  
Vol 22 (27) ◽  
pp. 4891-4899 ◽  
Author(s):  
N. F. BELL
Keyword(s):  
Neutrino Mass ◽  
Magnetic Moment ◽  
Magnetic Moments ◽  
New Physics ◽  
Upper Bounds ◽  
Radiative Corrections ◽  
Neutrino Magnetic Moment ◽  
Majorana Neutrinos ◽  
Model Independent ◽  
Moment Bounds

The existence of a neutrino magnetic moment implies contributions to the neutrino mass via radiative corrections. We derive model-independent "naturalness" upper bounds on the magnetic moments of Dirac and Majorana neutrinos, generated by physics above the electroweak scale. For Dirac neutrinos, the bound is several orders of magnitude more stringent than present experimental limits. However, for Majorana neutrinos the magnetic moment bounds are weaker than present experimental limits if μν is generated by new physics at ~ 1 TeV , and surpass current experimental sensitivity only for new physics scales > 10 – 100 TeV . The discovery of a neutrino magnetic moment near present limits would thus signify that neutrinos are Majorana particles.

Determination of the magnetic moments of 6Li and 7Li nuclei using an NMR spectrometer that records signals from two nuclei simultaneously

2020 ◽  
pp. 3-8
Author(s):  
Yu. I. Neronov
Keyword(s):  
Experimental Data ◽  
Magnetic Moment ◽  
Theoretical Calculations ◽  
Magnetic Moments ◽  
Systematic Errors ◽  
Simultaneous Recording ◽  
Resonant Frequencies ◽  
Low Concentration ◽  
Order Of Magnitude

The ratio of NMR frequencies of lithium isotopes was determined: with an error of 4,9·10–10. We used a spectrometer mode with simultaneous recording of signals from two cores, which allows us to reduce random and systematic errors by an order of magnitude. The ratio of the resonant frequencies of water protons and 7Li ions was determined: with an error of 3,5·10–9 for solutions with an extremely low concentration of LiOH*H2O salt in water and at a temperature of 25 °C. Based on the data obtained, the magnetic moments of lithium nuclei were calculated. The known data on the magnetic moment of the proton and data on the electronic shielding of these nuclei were used. The comparison of experimental data on µ(6Li) and µ(7Li) with data from theoretical calculations is discussed.

A CLASS OF MODELS WITH LARGE NEUTRINO MAGNETIC MOMENT

1994 ◽  
Vol 09 (12) ◽  
pp. 2013-2032 ◽  
Author(s):  
DARWIN CHANG ◽  
W.-Y. KEUNG ◽  
IVAN PHILLIPS
Keyword(s):  
Neutrino Mass ◽  
Magnetic Moment ◽  
Magnetic Moments ◽  
Neutrino Masses ◽  
Symmetry Principle ◽  
Neutrino Magnetic Moment ◽  
Symmetry Principles

We show how a list of symmetry principles can be used to generate a class of models in which the neutrino masses are suppressed while relatively large magnetic moments are allowed. The simplest example is a model for neutrino mass proposed by Zee some time ago. We show how the model can be improved based on the symmetry principle and we also demonstrate other models in this class which avoid some of the weakness in the simplest model.

scholarly journals Neutron star kick velocity induced by neutrino chirality flip and a lower bound for the neutrino magnetic moment

2021 ◽  
Author(s):  
Alejandro Ayala ◽  
Santiago Bernal Langarica ◽  
Saul Hernández‐Ortiz ◽  
Luis Alberto Hernández ◽  
Daryel Manreza‐Paret
Keyword(s):  
Neutron Star ◽  
Lower Bound ◽  
Magnetic Moment ◽  
Neutrino Magnetic Moment

scholarly journals Probing neutrino magnetic moment at the Jinping neutrino experiment

2021 ◽  
Vol 2021 (8) ◽  
Author(s):  
Baobiao Yue ◽  
Jiajun Liao ◽  
Jiajie Ling
Keyword(s):  
Magnetic Moment ◽  
Liquid Scintillator ◽  
Solar Neutrinos ◽  
Electron Neutrino ◽  
Neutrino Experiment ◽  
Neutrino Magnetic Moment ◽  
Systematic Uncertainties ◽  
Electron Recoil ◽  
Massive Neutrinos ◽  
Highly Correlated

Abstract Neutrino magnetic moment (νMM) is an important property of massive neutrinos. The recent anomalous excess at few keV electronic recoils observed by the XENON1T collaboration might indicate a ∼ 2.2 × 10−11μB effective neutrino magnetic moment ($$ {\mu}_{\nu}^{\mathrm{eff}} $$ μ ν eff ) from solar neutrinos. Therefore, it is essential to carry out the νMM searches at a different experiment to confirm or exclude such a hypothesis. We study the feasibility of doing νMM measurement with 4 kton fiducial mass at Jinping neutrino experiment (Jinping) using electron recoil data from both natural and artificial neutrino sources. The sensitivity of $$ {\mu}_{\nu}^{\mathrm{eff}} $$ μ ν eff can reach < 1.2 × 10−11μB at 90% C.L. with 10-year data taking of solar neutrinos. Besides the abundance of the intrinsic low energy background 14C and 85Kr in the liquid scintillator, we find the sensitivity to νMM is highly correlated with the systematic uncertainties of pp and 85Kr. Reducing systematic uncertainties (pp and 85Kr) and the intrinsic background (14C and 85Kr) can help to improve sensitivities below these levels and reach the region of astrophysical interest. With a 3 mega-Curie (MCi) artificial neutrino source 51Cr installed at Jinping neutrino detector for 55 days, it could give us a sensitivity to the electron neutrino magnetic moment ($$ {\mu}_{\nu_e} $$ μ ν e ) with < 1.1 × 10−11μB at 90% C.L. . With the combination of those two measurements, the flavor structure of the neutrino magnetic moment can be also probed at Jinping.

scholarly journals Spin Gapless Semiconductor–Nonmagnetic Semiconductor Transitions in Fe-Doped Ti2CoSi: First-Principle Calculations

2018 ◽  
Vol 8 (11) ◽  
pp. 2200 ◽  
Author(s):  
Yu Feng ◽  
Zhou Cui ◽  
Ming-sheng Wei ◽  
Bo Wu ◽  
Sikander Azam
Keyword(s):  
Magnetic Moment ◽  
Electronic Structures ◽  
Magnetic Moments ◽  
Total Magnetic Moment ◽  
First Principle ◽  
Half Metallic ◽  
Heusler Compound ◽  
First Principle Calculations ◽  
Metallic Ferromagnet

Employing first-principle calculations, we investigated the influence of the impurity, Fe atom, on magnetism and electronic structures of Heusler compound Ti2CoSi, which is a spin gapless semiconductor (SGS). When the impurity, Fe atom, intervened, Ti2CoSi lost its SGS property. As TiA atoms (which locate at (0, 0, 0) site) are completely occupied by Fe, the compound converts to half-metallic ferromagnet (HMF) TiFeCoSi. During this SGS→HMF transition, the total magnetic moment linearly decreases as Fe concentration increases, following the Slate–Pauling rule well. When all Co atoms are substituted by Fe, the compound converts to nonmagnetic semiconductor Fe2TiSi. During this HMF→nonmagnetic semiconductor transition, when Fe concentration y ranges from y = 0.125 to y = 0.625, the magnetic moment of Fe atom is positive and linearly decreases, while those of impurity Fe and TiB (which locate at (0.25, 0.25, 0.25) site) are negative and linearly increase. When the impurity Fe concentration reaches up to y = 1, the magnetic moments of Ti, Fe, and Si return to zero, and the compound is a nonmagnetic semiconductor.

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