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Note: This page contains sample records for the topic "neutrino mass mixing" from the National Library of EnergyBeta (NLEBeta).
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1

Models of Neutrino Masses and Mixing  

E-Print Network (OSTI)

Neutrino physics has entered an era of precision measurements. With these precise measurements, we may be able to distinguish different models that have been constructed to explain the small neutrino masses and the large mixing among them. In this talk, I review some of the existing theoretical models and their predictions for neutrino oscillations.

Mu-Chun Chen

2007-06-14T23:59:59.000Z

2

Phenomenological relations for neutrino masses and mixing parameters  

SciTech Connect

Phenomenological relations for masses, angles, and CP phases in the neutrino mixing matrix are proposed with allowance for available experimental data. For the case of CP violation in the lepton sector, an analysis of the possible structure of the neutrino mass matrix and a calculation of the neutrino mass features and the Dirac CP phase for the bimodal-neutrino model are performed. The values obtained in this way can be used to interpret and predict the results of various neutrino experiments.

Khruschov, V. V., E-mail: khru@imp.kiae.ru [National Research Center Kurchatov Institute (Russian Federation)

2013-11-15T23:59:59.000Z

3

Review Paper. Neutrino masses, mixing and oscillations  

Science Journals Connector (OSTI)

...experiments and experiments on the search for neutrinoless double beta-decay are briefly discussed. Neutrino Masses|Neutrino Oscillations|Neutrinoless Double beta-Decay| 10.1098/rspa.2003.1263 REVIEW PAPER...

2004-01-01T23:59:59.000Z

4

Review Paper. Neutrino masses, mixing and oscillations  

Science Journals Connector (OSTI)

...experiments on the search for neutrinoless...experiments on the search for neutrinoless...If neutrino fields enter only in the SM Lagrangians...is a neutrino mass term, which does not...i) Dirac mass term LD = - R MD L + h...Sterile fields do not enter into the standard...

2004-01-01T23:59:59.000Z

5

Neutrino Mixing  

E-Print Network (OSTI)

In this review we present the main features of the current status of neutrino physics. After a review of the theory of neutrino mixing and oscillations, we discuss the current status of solar and atmospheric neutrino oscillation experiments. We show that the current data can be nicely accommodated in the framework of three-neutrino mixing. We discuss also the problem of the determination of the absolute neutrino mass scale through Tritium beta-decay experiments and astrophysical observations, and the exploration of the Majorana nature of massive neutrinos through neutrinoless double-beta decay experiments. Finally, future prospects are briefly discussed.

Carlo Giunti; Marco Laveder

2004-10-01T23:59:59.000Z

6

Results on neutrino mass and mixing from Super Kamiokande  

E-Print Network (OSTI)

the mass 2 dierene above 1 eV , sale than disussed in thisallowing to probe mass sales smaller than 1 eV is neutrino

Kielczewska, Danuta; Super Kamiokande Collaboration, .; K2K Collaboration, .

2002-01-01T23:59:59.000Z

7

Neutrino mass and mixing: from theory to experiment  

Science Journals Connector (OSTI)

The origin of fermion mass hierarchies and mixings is one of the unresolved and most difficult problems in high-energy physics. One possibility to address the flavour problems is by extending the standard model to include a family symmetry. In the recent years it has become very popular to use non-Abelian discrete flavour symmetries because of their power in the prediction of the large leptonic mixing angles relevant for neutrino oscillation experiments. Here we give an introduction to the flavour problem and to discrete groups that have been used to attempt a solution for it. We review the current status of models in light of the recent measurement of the reactor angle, and we consider different model-building directions taken. The use of the flavons or multi-Higgs scalars in model building is discussed as well as the direct versus indirect approaches. We also focus on the possibility of experimentally distinguishing flavour symmetry models by means of mixing sum rules and mass sum rules. In fact, we illustrate in this review the complete path from mathematics, via model building, to experiments, so that any reader interested in starting work in the field could use this text as a starting point in order to obtain a broad overview of the different subject areas.

Stephen F King; Alexander Merle; Stefano Morisi; Yusuke Shimizu; Morimitsu Tanimoto

2014-01-01T23:59:59.000Z

8

Neutrino Mass and Mixing: from Theory to Experiment  

E-Print Network (OSTI)

The origin of fermion mass hierarchies and mixings is one of the unresolved and most difficult problem in high-energy physics. One possibility to address the flavour problem is by extending the Standard Model to include a family symmetry. In the recent years it has become very popular to use non-Abelian discrete flavour symmetries because of their power in the prediction of the large leptonic mixing angles relevant for neutrino oscillation experiments. Here we give an introduction to the flavour problem and to discrete groups which have been used to attempt a solution for it. We review the current status of models in the light of the recent measurement of the reactor angle and we consider different model building directions taken. The use of the flavons or multi Higgs scalars in model building is discussed as well as the direct vs. indirect approaches. We also focus on the possibility to distinguish experimentally flavour symmetry models by means of mixing sum rules and mass sum rules. In fact, we illustrate ...

King, Stephen F; Morisi, Stefano; Shimizu, Yusuke; Tanimoto, Morimitsu

2014-01-01T23:59:59.000Z

9

Neutrino Mass and Mixing: from Theory to Experiment  

E-Print Network (OSTI)

The origin of fermion mass hierarchies and mixings is one of the unresolved and most difficult problem in high-energy physics. One possibility to address the flavour problem is by extending the Standard Model to include a family symmetry. In the recent years it has become very popular to use non-Abelian discrete flavour symmetries because of their power in the prediction of the large leptonic mixing angles relevant for neutrino oscillation experiments. Here we give an introduction to the flavour problem and to discrete groups which have been used to attempt a solution for it. We review the current status of models in the light of the recent measurement of the reactor angle and we consider different model building directions taken. The use of the flavons or multi Higgs scalars in model building is discussed as well as the direct vs. indirect approaches. We also focus on the possibility to distinguish experimentally flavour symmetry models by means of mixing sum rules and mass sum rules. In fact, we illustrate in this review the complete path from mathematics, via model building, to experiments, so that any reader interested to start working in the field could use this text as a starting point in order to get a broad overview of the different subject areas.

Stephen F. King; Alexander Merle; Stefano Morisi; Yusuke Shimizu; Morimitsu Tanimoto

2014-02-18T23:59:59.000Z

10

Global analysis of neutrino masses, mixings, and phases: Entering the era of leptonic CP violation searches  

Science Journals Connector (OSTI)

We perform a global analysis of neutrino oscillation data, including high-precision measurements of the neutrino mixing angle ?13 at reactor experiments, which have confirmed previous indications in favor of ?13>0. Recent data presented at the Neutrino 2012 conference are also included. We focus on the correlations between ?13 and the mixing angle ?23, as well as between ?13 and the neutrino CP-violation phase ?. We find interesting indications for ?23mass hierarchy.

G. L. Fogli; E. Lisi; A. Marrone; D. Montanino; A. Palazzo; A. M. Rotunno

2012-07-23T23:59:59.000Z

11

Neutrino Masses, Lepton Flavor Mixing and Leptogenesis in the Minimal Seesaw Model  

E-Print Network (OSTI)

We present a review of neutrino phenomenology in the minimal seesaw model (MSM), an economical and intriguing extension of the Standard Model with only two heavy right-handed Majorana neutrinos. Given current neutrino oscillation data, the MSM can predict the neutrino mass spectrum and constrain the effective masses of the tritium beta decay and the neutrinoless double-beta decay. We outline five distinct schemes to parameterize the neutrino Yukawa-coupling matrix of the MSM. The lepton flavor mixing and baryogenesis via leptogenesis are investigated in some detail by taking account of possible texture zeros of the Dirac neutrino mass matrix. We derive an upper bound on the CP-violating asymmetry in the decay of the lighter right-handed Majorana neutrino. The effects of the renormalization-group evolution on the neutrino mixing parameters are analyzed, and the correlation between the CP-violating phenomena at low and high energies is highlighted. We show that the observed matter-antimatter asymmetry of the Universe can naturally be interpreted through the resonant leptogenesis mechanism at the TeV scale. The lepton-flavor-violating rare decays, such as $\\mu \\to e + \\gamma$, are also discussed in the supersymmetric extension of the MSM.

Wan-lei Guo; Zhi-zhong Xing; Shun Zhou

2006-12-05T23:59:59.000Z

12

Supernova observations for neutrino mixing parameters  

SciTech Connect

The neutrino spectra from a future galactic core collapse supernova could reveal information on the neutrino mixing pattern, especially on {theta}{sub 13} and the mass hierarchy. I briefly outline our current understanding of neutrino flavor conversions inside a supernova, and point out possible signatures of various neutrino mixing scenarios that the neutrino detectors should look for. Supernova neutrinos provide a probe for {theta}{sub 13} and mass hierarchy that is complementary to, and sometimes even better than, the current and proposed terrestrial neutrino oscillation experiments.

Dighe, Amol [Department of Theoretical Physics, Tata Institute of Fundamental Research, 1, Homi Bhabha Road, Colaba, Mumbai 400005 (India)

2011-10-06T23:59:59.000Z

13

neutrino_mixing_s805.dvi  

NLE Websites -- All DOE Office Websites (Extended Search)

NEUTRINO NEUTRINO PHYSICS AS EXPLORED BY FLAVOR CHANGE Written May 2002 by B. Kayser (Fermilab). I. The physics of flavor change: The rather convincing evidence that atmospheric neutrinos change from one flavor to another has now been joined by new, very strong evidence that the solar neutrinos do this as well. Neutrino flavor change implies that neutrinos have nonzero masses. That is, there is a spectrum of three or more neutrino mass eigenstates, ν 1 , ν 2 , ν 3 , . . ., that are the analogues of the charged-lepton mass eigenstates, e, µ, and τ . Neutrino flavor change also implies leptonic mixing. That is, the weak interaction coupling the W boson to a charged lepton and a neutrino can couple any charged-lepton mass eigenstate α to any neutrino mass eigenstate ν i . Here, α = e, µ, or τ , and e is the electron, etc. Leptonic W + decay can yield a particular + α in association with any ν i . The amplitude

14

Observables in Neutrino Mass Spectroscopy Using Atoms  

E-Print Network (OSTI)

The process of collective de-excitation of atoms in a metastable level into emission mode of a single photon plus a neutrino pair, called radiative emission of neutrino pair (RENP), is sensitive to the absolute neutrino mass scale, to the neutrino mass hierarchy and to the nature (Dirac or Majorana) of massive neutrinos. We investigate how the indicated neutrino mass and mixing observables can be determined from the measurement of the corresponding continuous photon spectrum taking the example of a transition between specific levels of the Yb atom. The possibility of determining the nature of massive neutrinos and, if neutrinos are Majorana fermions, of obtaining information about the Majorana phases in the neutrino mixing matrix, is analyzed in the cases of normal hierarchical, inverted hierarchical and quasi-degenerate types of neutrino mass spectrum. We find, in particular, that the sensitivity to the nature of massive neutrinos depends critically on the atomic level energy difference relevant in the RENP.

D. N. Dinh; S. T. Petcov; N. Sasao; M. Tanaka; M. Yoshimura

2012-09-21T23:59:59.000Z

15

Three Flavor Neutrino Mixing and Dark Energy Above GUT Scale  

Science Journals Connector (OSTI)

Neutrino mixing lead to a non zero contribution to the dark energy of the universe. We assume that the neutrino masses and mixing arise through physics at a scale intermediate ... the electroweak scale. The mecha...

Bipin Singh Koranga; Rajesh Pandey

2011-05-01T23:59:59.000Z

16

Dark energy, cosmological constant and neutrino mixing  

E-Print Network (OSTI)

The today estimated value of dark energy can be achieved by the vacuum condensate induced by neutrino mixing phenomenon. Such a tiny value is recovered for a cut-off of the order of Planck scale and it is linked to the sub eV neutrino mass scale. Contributions to dark energy from auxiliary fields or mechanisms are not necessary in this approach.

A. Capolupo; S. Capozziello; G. Vitiello

2007-05-02T23:59:59.000Z

17

Lepton mixing under the lepton charge nonconservation, neutrino masses and oscillations and the 'forbidden' decay Micro-Sign {sup -} {yields} e{sup -} + {gamma}  

SciTech Connect

The lepton-charge (L{sub e}, L{sub {mu}}, L{sub {tau}}) nonconserving interaction leads to the mixing of the electron, muon, and tau neutrinos, which manifests itself in spatial oscillations of a neutrino beam, and also to the mixing of the electron, negative muon, and tau lepton, which, in particular, may be the cause of the 'forbidden' radiative decay of the negative muon into the electron and {gamma} quantum. Under the assumption that the nondiagonal elements of the mass matrices for neutrinos and ordinary leptons, connected with the lepton charge nonconservation, are the same, and by performing the joint analysis of the experimental data on neutrino oscillations and experimental restriction for the probability of the decay Micro-Sign {sup -} {yields} e{sup -} + {gamma} per unit time, the following estimate for the lower bound of neutrino mass has been obtained: m{sup ({nu})} > 1.5 eV/c{sup 2}.

Lyuboshitz, V. L.; Lyuboshitz, V. V., E-mail: Valery.Lyuboshitz@jinr.ru [Joint Institute for Nuclear Research (Russian Federation)

2013-08-15T23:59:59.000Z

18

Double Beta Decay and the Absolute Neutrino Mass Scale  

E-Print Network (OSTI)

After a short review of the current status of three-neutrino mixing, the implications for the values of neutrino masses are discussed. The bounds on the absolute scale of neutrino masses from Tritium beta-decay and cosmological data are reviewed. Finally, we discuss the implications of three-neutrino mixing for neutrinoless double-beta decay.

Carlo Giunti

2003-08-20T23:59:59.000Z

19

Neutrino oscillations and mixings with three flavors  

Science Journals Connector (OSTI)

Global fits to all data of candidates for neutrino oscillations are presented in the framework of a three-flavor model. The analysis excludes mass regions where the MSW effect is important for the solar neutrino problem. The best fit gives ?1?28.9, ?2?4.2, ?3?45.0, m22-m12?2.8710-4 eV2, and m32-m22?1.11 eV2 indicating essentially maximal mixing between the two lightest neutrino mass eigenstates.

Tommy Ohlsson and Hkan Snellman

1999-10-07T23:59:59.000Z

20

Vacuum neutrino oscillations of solar neutrinos and lepton mass matrices  

Science Journals Connector (OSTI)

We consider the case that the solar neutrino deficit is due to vacuum oscillations. The lepton mass matrices with nearly bimaximal mixings are needed in order to explain both the solar and atmospheric neutrino deficit. A texture with the symmetry of flavor democracy or S3 has been investigated by taking account of the symmetry breaking terms of the charged lepton mass matrix. It is found that predicted mixings can be considerably changed from the neutrino mixings sin22???1 and sin22?atm?8/9 at the symmetric limit. The correlation between |Ue3| and |Ue1Ue2*| is also presented. The test of the model is discussed by focusing on the three flavor analyses in the solar neutrinos, atmospheric neutrinos, and long baseline experiments.

Morimitsu Tanimoto

1998-12-11T23:59:59.000Z

Note: This page contains sample records for the topic "neutrino mass mixing" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Effective Mass Matrix for Light Neutrinos Consistent with Solar and Atmospheric Neutrino Experiments  

E-Print Network (OSTI)

We propose an effective mass matrix for light neutrinos which is consistent with the mixing pattern indicated by solar and atmospheric neutrino experiments. Two scenarios for the mass eigenvalues are discussed and the connection with double beta decay is noted.

S. P. Rosen; Waikwok Kwong

1995-01-20T23:59:59.000Z

22

Sum rules of four-neutrino mixing in matter  

E-Print Network (OSTI)

Assuming the existence of one light sterile neutrino, we investigate the neutrino flavor mixing matrix in matter. Sum rules between the mixing parameters in vacuum and their counterparts in matter are derived. By using these new sum rules, we obtain the simple but exact expressions of the effective flavor mixing matrix in matter in terms of neutrino masses and the mixing parameters in vacuum. The rephasing invariants, sides of unitarity quadrangles and oscillation probabilities in matter are also achieved. Our model-independent results will be very helpful for analyzing flavor mixing and CP violation in the future long-baseline neutrino oscillation experiments.

He Zhang

2006-06-04T23:59:59.000Z

23

Can Neutrinos be Degenerate in Mass?  

E-Print Network (OSTI)

We reconsider the possibility that the masses of the three light neutrinos of the Standard Model might be almost degenerate and close to the present upper limits from Tritium beta decay and cosmology. In such a scenario, the cancellations required by the latest upper limit on neutrinoless double-beta decay enforce near-maximal mixing that may be compatible only with the vacuum-oscillation scenario for solar neutrinos. We argue that the mixing angles yielded by degenerate neutrino mass-matrix textures are not in general stable under small perturbations. We evaluate within the MSSM the generation-dependent one-loop renormalization of neutrino mass-matrix textures that yielded degenerate masses and large mixing at the tree level. We find that m_{nu_e} > m_{nu_mu} > m_{nu_tau} after renormalization, excluding MSW effects on solar neutrinos. We verify that bimaximal mixing is not stable, and show that the renormalized masses and mixing angles are not compatible with all the experimental constraints, even for tanbeta as low as unity. These results hold whether the neutrino masses are generated by a see-saw mechanism with heavy neutrinos weighing approx. 10^{13} GeV or by non-renormalizable interactions at a scale approx. 10^5 GeV. We also comment on the corresponding renormalization effects in the minimal Standard Model, in which m_{nu_e} < m_{nu_mu} < m_{nu_tau}. Although a solar MSW effect is now possible, the perturbed neutrino masses and mixings are still not compatible with atmospheric- and solar-neutrino data.

John Ellis; Smaragda Lola

1999-04-13T23:59:59.000Z

24

Constrained analytical interrelations in neutrino mixing  

E-Print Network (OSTI)

Hermitian squared mass matrices of charged leptons and light neutrinos in the flavor basis are studied under general additive lowest order perturbations away from the tribimaximal (TBM) limit in which a weak basis with mass diagonal charged leptons is chosen. Simple analytical expressions are found for the three measurable TBM-deviants in terms of perturbation parameters appearing in the neutrino and charged lepton eigenstates in the flavor basis. Taking unnatural cancellations to be absent and charged lepton perturbation parameters to be small, constrained analytical and testable interrelations are derived among neutrino masses, mixing angles and the amount of CP-violation, posing the challenge of verification to forthcoming experiments at the intensity frontier.

Brahmachari, Biswajoy

2014-01-01T23:59:59.000Z

25

Constrained analytical interrelations in neutrino mixing  

E-Print Network (OSTI)

Hermitian squared mass matrices of charged leptons and light neutrinos in the flavor basis are studied under general additive lowest order perturbations away from the tribimaximal (TBM) limit in which a weak basis with mass diagonal charged leptons is chosen. Simple analytical expressions are found for the three measurable TBM-deviants in terms of perturbation parameters appearing in the neutrino and charged lepton eigenstates in the flavor basis. Taking unnatural cancellations to be absent and charged lepton perturbation parameters to be small, constrained analytical and testable interrelations are derived among neutrino masses, mixing angles and the amount of CP-violation, posing the challenge of verification to forthcoming experiments at the intensity frontier.

Biswajoy Brahmachari; Probir Roy

2014-03-09T23:59:59.000Z

26

Neutrino mixing, flavor states and dark energy  

E-Print Network (OSTI)

We shortly summarize the quantum field theory formalism for the neutrino mixing and report on recent results showing that the vacuum condensate induced by neutrino mixing can be interpreted as a dark energy component of the Universe.

M. Blasone; A. Capolupo; S. Capozziello; G. Vitiello

2007-11-06T23:59:59.000Z

27

Dark energy induced by neutrino mixing  

E-Print Network (OSTI)

The energy content of the vacuum condensate induced by the neutrino mixing is interpreted as dynamically evolving dark energy.

Antonio Capolupo; Salvatore Capozziello; Giuseppe Vitiello

2006-12-05T23:59:59.000Z

28

Calculable lepton masses, seesaw relations and four neutrino mixings in a 3-3-1 model with extra U(1) symmetry  

E-Print Network (OSTI)

We propose a scheme in that the masses of the heavier leptons obey seesaw type relations. The light lepton masses, except the electron and the electron neutrino ones are generated by one loop level radiative corrections. We work in a version of the 3-3-1 electroweak model that predicts singlets (charged and neutral) of heavy leptons beyond the known ones. An extra U(1)_Omega symmetry is introduced in order to avoid the light leptons get masses at the tree level. The electron mass induces an explicit symmetry breaking at U(1). We discuss also the mixing matrix among four neutrinos. The new energy scale required is not higher than a few TeV.

Nelson V. Cortez; Mauro D. Tonasse

2005-10-11T23:59:59.000Z

29

Phenomenology of Absolute Neutrino Masses  

E-Print Network (OSTI)

The phenomenology of absolute neutrino masses is reviewed, focusing on tritium beta decay, cosmological measurements and neutrinoless double-beta decay.

Carlo Giunti

2004-12-11T23:59:59.000Z

30

Flavor S_4 times Z_2 symmetry and neutrino mixing  

E-Print Network (OSTI)

We present a model of the lepton masses and flavor mixing based on the discrete group $S_4 \\times Z_2$. In this model, all the charged leptons and neutrinos are assigned to the $3_\\alpha$ representation of $S_4$ in the Yamanouchi bases. The charged lepton and neutrino masses are mainly determined by the vacuum expectation value structures of the Higgs fields. A nearly tri-bimaximal lepton flavor mixing pattern, which is in agreement with the current experimental results, can be accommodated in our model. The neutrino mass spectrum takes the nearly degenerate pattern, and thus can be well tested in the future precise experiments.

He Zhang

2006-12-18T23:59:59.000Z

31

Solar mass-varying neutrino oscillations  

E-Print Network (OSTI)

We propose that the solar neutrino deficit may be due to oscillations of mass-varying neutrinos (MaVaNs). This scenario elucidates solar neutrino data beautifully while remaining comfortably compatible with atmospheric neutrino and K2K data...

Marfatia, Danny; Huber, P.; Barger, V.

2005-11-18T23:59:59.000Z

32

Simple neutrino mass matrix with only two free parameters  

E-Print Network (OSTI)

A simple form of neutrino mass matrix which has only two free parameters is proposed from a phenomenological point of view. Using this mass matrix, we succeed to reproduce all the observed values for the MNS lepton mixing angles and the neutrino mass squared difference ratio. Our model also predicts $\\delta_{\

Hiroyuki Nishiura; Takeshi Fukuyama

2014-05-10T23:59:59.000Z

33

Simple neutrino mass matrix with only two free parameters  

E-Print Network (OSTI)

A simple form of neutrino mass matrix which has only two free parameters is proposed from a phenomenological point of view. Using this mass matrix, we succeed to reproduce all the observed values for the MNS lepton mixing angles and the neutrino mass squared difference ratio. Our model also predicts $\\delta_{\

Nishiura, Hiroyuki

2014-01-01T23:59:59.000Z

34

Absolute Values of Neutrino Masses: Status and Prospects  

E-Print Network (OSTI)

Compelling evidences in favor of neutrino masses and mixing obtained in the last years in Super-Kamiokande, SNO, KamLAND and other neutrino experiments made the physics of massive and mixed neutrinos a frontier field of research in particle physics and astrophysics. There are many open problems in this new field. In this review we consider the problem of the absolute values of neutrino masses, which apparently is the most difficult one from the experimental point of view. We discuss the present limits and the future prospects of beta-decay neutrino mass measurements and neutrinoless double-beta decay. We consider the important problem of the calculation of nuclear matrix elements of neutrinoless double-beta decay and discuss the possibility to check the results of different model calculations of the nuclear matrix elements through their comparison with the experimental data. We discuss the upper bound of the total mass of neutrinos that was obtained recently from the data of the 2dF Galaxy Redshift Survey and other cosmological data and we discuss future prospects of the cosmological measurements of the total mass of neutrinos. We discuss also the possibility to obtain information on neutrino masses from the observation of the ultra high-energy cosmic rays (beyond the GZK cutoff). Finally, we review the main aspects of the physics of core-collapse supernovae, the limits on the absolute values of neutrino masses from the observation of SN1987A neutrinos and the future prospects of supernova neutrino detection.

S. M. Bilenky; C. Giunti; J. A. Grifols; E. Masso

2003-03-27T23:59:59.000Z

35

Majorana neutrino masses in the three-flavor Pauli model  

SciTech Connect

A special Majorana model for three neutrino flavors is developed on the basis of the Pauli transformation group. In this model, the neutrinos possess a partially conserved generalized lepton (Pauli) charge that makes it possible to discriminate between neutrinos of different type. It is shown that, within the model in question, a transition from the basic 'mass' representation, where the average value of this charge is zero, to the representation associated with physical neutrinos characterized by specific Pauli 'flavor' charges establishes a relation between the neutrino mixing angles {theta}{sub mix,12}, {theta}{sub mix,23}, and {theta}{sub mix,13} and an additional relation between the Majorana neutrino masses. The Lagrangian mass part, which includes a term invariant under Pauli transformations and a representation-dependent term, concurrently assumes a 'quasi-Dirac' form. With allowance for these relations, the existing set of experimental data on the features of neutrino oscillations makes it possible to obtain quantitative estimates for the absolute values of the neutrino masses and the 2{beta}-decay mass parameter m{sub {beta}{beta}} and a number of additional constraints on the neutrino mixing angles.

Gaponov, Yu. V. [Russian Research Centre Kurchatov Institute (Russian Federation)

2011-02-15T23:59:59.000Z

36

Neutrino Masses in Flipped SU(5)  

E-Print Network (OSTI)

We analyse the fermion masses and mixings in the flipped SU(5) model. The fermion mass matrices are evolved from the GUT scale down to $m_W$ by solving the renormalization group equations for the Yukawa couplings. The constraints imposed by the charged fermion data are then utilised to make predictions about the neutrino properties . It is found that the {\\it generalized } see-saw mechanism which occurs naturally in this model can provide {\\it i})a solution to the solar neutrino problem via the MSW mechanism and {\\it ii})a sufficiently large $\

Leontaris, George K

1993-01-01T23:59:59.000Z

37

Neutrino mixing and oscillations in astrophysical environments  

SciTech Connect

A brief review of the current status of neutrino mixing and oscillations in astrophysical environments, with particular emphasis on the Sun and core-collapse supernovae, is given. Implications of the existence of sterile states which mix with the active neutrinos are discussed.

Balantekin, A. B. [Physics Department, University of Wisconsin, Madison WI 53706 (United States)

2014-05-02T23:59:59.000Z

38

Current Direct Neutrino Mass Experiments  

E-Print Network (OSTI)

In this contribution we review the status and perspectives of direct neutrino mass experiments. These experiments investigate the kinematics of $\\beta$-decays of specific isotopes ($^3$H, $^{187}$Re, $^{163}$Ho) to derive model-independent information on the averaged electron (anti-) neutrino mass, which is formed by the incoherent sum of the neutrino mass eigenstates contributing to the electron neutrino. We first review the kinematics of $\\beta$-decay and the determination of the neutrino mass, before giving a brief overview of past neutrino mass measurements (SN1987a-ToF studies, Mainz and Troitsk experiments for $^3$H, cryo-bolometers for $^{187}$Re). We then describe the Karlsruhe Tritium Neutrino (KATRIN) experiment which is currently under construction at Karlsruhe Institute of Technology. The large-scale setup will use the MAC-E-Filter principle pioneered earlier to push the sensitivity down to a value of 200 meV(90% C.L.). KATRIN faces many technological challenges that have to be resolved with regar...

Drexlin, G; Mertens, S; Weinheimer, C

2013-01-01T23:59:59.000Z

39

Testable constraint on near-tribimaximal neutrino mixing  

E-Print Network (OSTI)

General lowest order perturbations to hermitian squared mass matrices of leptons are considered away from the tribimaximal (TBM) limit in which a weak flavor basis with mass diagonal charged leptons is chosen. The three measurable TBM-deviants are expressed linearly in terms of perturbation induced dimensionless coefficients appearing in the charged lepton and neutrino flavor eigenstates. With unnatural cancellations assumed to be absent and the charged lepton perturbation contributions to their flavor eigenstates argued to be small, we analytically derive that a deviation from maximal atmospheric neutrino mixing and CP violation in neutrino oscillations cannot both be observably large, posing the challenge of verification to forthcoming experiments at the intensity frontier.

Brahmachari, Biswajoy

2014-01-01T23:59:59.000Z

40

Testable constraint on near-tribimaximal neutrino mixing  

E-Print Network (OSTI)

General lowest order perturbations to hermitian squared mass matrices of leptons are considered away from the tribimaximal (TBM) limit in which a weak flavor basis with mass diagonal charged leptons is chosen. The three measurable TBM-deviants are expressed linearly in terms of perturbation induced dimensionless coefficients appearing in the charged lepton and neutrino flavor eigenstates. With unnatural cancellations assumed to be absent and the charged lepton perturbation contributions to their flavor eigenstates argued to be small, we analytically derive that a deviation from maximal atmospheric neutrino mixing and CP violation in neutrino oscillations cannot both be observably large, posing the challenge of verification to forthcoming experiments at the intensity frontier.

Biswajoy Brahmachari; Probir Roy

2014-07-20T23:59:59.000Z

Note: This page contains sample records for the topic "neutrino mass mixing" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

On the muon neutrino mass  

E-Print Network (OSTI)

During the runs of the PS 179 experiment at LEAR of CERN, we photographed an event of antiproton-Ne absorption, with a complete pi+ -> mu+ ->e+ chain. From the vertex of the reaction a very slow energy pi+ was emitted. The pi+ decays into a mu+ and subsequently the mu+ decays into a positron. At the first decay vertex a muon neutrino was emitted and at the second decay vertex an electron neutrino and a muon antineutrino. Measuring the pion and muon tracks and applying the momentum and energy conservation and using a classical statistical interval estimator, we obtained an experimental upper limit for the muon neutrino mass: m_nu < 2.2 MeV at a 90% confidence level. A statistical analysis has been performed of the factors contributing to the square value of the neutrino mass limit.

N. Angelov; F. Balestra; Yu. Batusov; A. Bianconi; M. P. Bussa; L. Busso; L. Ferrero; R. Garfagnini; I. Gnesi; E. Lodi Rizzini; A. Maggiora; D. Panzieri; G. Piragino; G. Pontecorvo; F. Tosello; L. Venturelli

2006-05-03T23:59:59.000Z

42

What are the Neutrino Masses  

E-Print Network (OSTI)

The possible source of the production of neutrino with large masses is considered. For this purpose the reaction nu+n to e+p+gamma, in which the electron in neW+ vertex is produced off-mass-shell, is studied.

V. P. Efrosinin

2009-04-03T23:59:59.000Z

43

Small scales structures and neutrino masses  

E-Print Network (OSTI)

We review the impact of massive neutrinos on cosmological observables at the linear order. By means of N-body simulations we investigate the signatures left by neutrinos on the fully non-linear regime. We present the effects induced by massive neutrinos on the matter power spectrum, the halo mass function and on the halo-matter bias in massive neutrino cosmologies. We also investigate the clustering of cosmic neutrinos within galaxy clusters.

Villaescusa-Navarro, Francisco

2015-01-01T23:59:59.000Z

44

Graphene, neutrino mass and oscillation  

E-Print Network (OSTI)

A resolution of the Abraham-Minkowski dilemma is presented that other constant velocities can play the role of c in the theory of relativity. For example, in 2005 electrons of graphene were discovered to behave as if the coefficient is a Fermi velocity. Then we propose a conjecture for neutrinos to avoid the contradiction among two-component theory, negative rest mass-square and oscillation.

Z. Y. Wang

2009-09-10T23:59:59.000Z

45

Almost Maximal Lepton Mixing with Large T Violation in Neutrino Oscillations and Neutrinoless Double Beta Decay  

E-Print Network (OSTI)

We point out two simple but instructive possibilities to construct the charged lepton and neutrino mass matrices, from which the nearly bi-maximal neutrino mixing with large T violation can naturally emerge. The two lepton mixing scenarios are compatible very well with current experimental data on solar and atmospheric neutrino oscillations, and one of them may lead to an observable T-violating asymmetry between \

Zhi-zhong Xing

2001-07-02T23:59:59.000Z

46

Constraining Mass Spectra with Sterile Neutrinos from Neutrinoless Double Beta Decay, Tritium Beta Decay and Cosmology  

E-Print Network (OSTI)

We analyze the constraints on neutrino mass spectra with extra sterile neutrinos as implied by the LSND experiment. The various mass related observables in neutrinoless double beta decay, tritium beta decay and cosmology are discussed. Both neutrino oscillation results as well as recent cosmological neutrino mass bounds are taken into account. We find that some of the allowed mass patterns are severely restricted by the current constraints, in particular by the cosmological constraints on the total sum of neutrino masses and by the non-maximality of the solar neutrino mixing angle. Furthermore, we estimate the form of the four neutrino mass matrices and also comment on the situation in scenarios with two additional sterile neutrinos.

Srubabati Goswami; Werner Rodejohann

2006-05-18T23:59:59.000Z

47

Neutrino mixing and CP violation phases in Zee-Babu model  

E-Print Network (OSTI)

We show that the neutrino mass matrix of the Zee-Babu model is able to fit the most recent data on neutrino masses and mixing with large $\\theta_{13}$ and provides %the values of the Dirac and Majorana CP violation phases. For the normal hierarchy, the Majorana phases ($\\al_{2 1}, \\al_{3 1}$) are equal to zero, while for the inverted pattern, one phase ($\\al_{3 1}$) takes the value $2 \\pi$. The Dirac phase ($\\de$) is predicted to either $0$ or $\\pi$. The effective mass governing neutrinoless double beta decay and the sum of neutrino masses are consistent with the recent analysis. The model gives some regions of the parameters of neutrino mixing angles in both normal and inverted neutrino mass hierarchy.

Van Vien, Vo; Thu, Pham Ngoc

2014-01-01T23:59:59.000Z

48

The Invisible Axion and Neutrino Masses  

E-Print Network (OSTI)

We show that in any invisible axion model due to the effects of effective non-renormalizable interactions related to an energy scale near the Peccei-Quinn, grand unification or even the Planck scale, active neutrinos necessarily acquire masses in the sub-eV range. Moreover, if sterile neutrinos are also included and if appropriate cyclic $Z_N$ symmetries are imposed, it is possible that some of these neutrinos are heavy while others are light.

Alex G. Dias; V. Pleitez

2005-11-09T23:59:59.000Z

49

Frobenius group T13 and the canonical seesaw mechanism applied to neutrino mixing  

Science Journals Connector (OSTI)

The compatibility of the Frobenius group T13 with the canonical seesaw mechanism of neutrino mixing is examined. The standard model is extended minimally by introducing a family symmetry and three right-handed neutrinos. To fit experiments and place constraints on the possibilities, tribimaximal mixing is used as a guideline. The application of both a family symmetry group and the canonical seesaw mechanism naturally generates small neutrino masses. The various possibilities from combining these two models are listed. Enough constraints are produced to narrow down the parameters of the neutrino mass matrix to two. This is therefore a predictive model, where the physical neutrino masses and the allowed regions for neutrinoless double beta decay are suggested.

Christine Hartmann

2012-01-13T23:59:59.000Z

50

Mass Varying Neutrinos in the Sun  

E-Print Network (OSTI)

In this work we study the phenomenological consequences of the dependence of mass varying neutrinos on the neutrino density in the Sun, which we precisely compute in each point along the neutrino trajectory. We find that a generic characteristic of these scenarios is that they establish a connection between the effective Delta m^2 in the Sun and the absolute neutrino mass scale. This does not lead to any new allowed region in the oscillation parameter space. On the contrary, due to this effect, the description of solar neutrino data worsens for large absolute mass. As a consequence a lower bound on the level of degeneracy can be derived from the combined analysis of the solar and KamLAND data. In particular this implies that the analysis favours normal over inverted mass orderings. These results, in combination with a positive independent determination of the absolute neutrino mass, can be used as a test of these scenarios together with a precise determination of the energy dependence of the survival probability of solar neutrinos, in particular for low energies.

Marco Cirelli; M. C. Gonzalez-Garcia; Carlos Pena-Garay

2005-07-08T23:59:59.000Z

51

Neutrino masses, leptogenesis, and sterile neutrino dark matter  

E-Print Network (OSTI)

We analyze a scenario in which the lightest heavy neutrino $N_1$ is a dark matter candidate and the second- heaviest neutrino $N_2$ decays producing a lepton number. If $N_1$ were in thermal equilibrium, its energy density today would be much larger than that of the observed dark matter, so we consider energy injection by the decay of $N_2$. In this paper, we show the parameters of this scenario that give the correct abundances of dark matter and baryonic matter and also induce the observed neutrino masses. This model can explain a possible sterile neutrino dark matter signal of $M_1$=7 keV in the x-ray observation of x-ray multi-mirror mission.

Takanao Tsuyuki

2014-07-20T23:59:59.000Z

52

Neutrino mass matrix with U(2) flavor symmetry and neutrino oscillations  

Science Journals Connector (OSTI)

The three neutrino mass matrices in the SU(5)U(2) model are studied focusing on neutrino oscillation experiments. The atmospheric neutrino anomaly could be explained by a large ??-?? oscillation. The long baseline experiments are expected to detect signatures of the neutrino oscillation even if the atmospheric neutrino anomaly is not due to the neutrino oscillation. However, the model cannot solve the solar neutrino deficit while it could be reconciled with the LSND data.

Morimitsu Tanimoto

1998-02-01T23:59:59.000Z

53

Neutrinoless double-beta decay with three or four neutrino mixing  

E-Print Network (OSTI)

Considering the scheme with mixing of three neutrinos and a mass hierarchy that can accommodate the results of solar and atmospheric neutrino experiments, it is shown that the results of solar neutrino experiments imply a lower bound for the effective Majorana mass in neutrinoless double-beta decay, under the natural assumptions that massive neutrinos are Majorana particles and there are no unlikely fine-tuned cancellations among the contributions of the different neutrino masses. Considering the four-neutrino schemes that can accommodate also the results of the LSND experiment, it is shown that only one of them is compatible with the results of neutrinoless double-beta decay experiments and with the measurement of the abundances of primordial elements produced in Big-Bang Nucleosynthesis. It is shown that in this scheme, under the assumptions that massive neutrinos are Majorana particles and there are no cancellations among the contributions of the different neutrino masses, the results of the LSND experiment imply a lower bound for the effective Majorana mass in neutrinoless double-beta decay.

C. Giunti

1999-06-07T23:59:59.000Z

54

Arbitrary mass Majorana neutrinos in neutrinoless double beta decay  

E-Print Network (OSTI)

We revisit the mechanism of neutrinoless double beta (NLDBD) decay mediated by the exchange with the heavy Majorana neutrino N of arbitrary mass mN, slightly mixed with the electron neutrino. By assuming the dominance of this mechanism, we update the well-known NLDBD-decay exclusion plot in the mass-mixing angle plane taking into account recent progress in the calculation of nuclear matrix elements within quasiparticle random phase approximation and improved experimental bounds on the NLDBD-decay half-life of Ge-76 and Xe-136. We also consider the known formula approximating the mN dependence of the NLDBD-decay nuclear matrix element in a simple explicit form. We analyze its accuracy and specify the corresponding parameters, allowing one to easily calculate the NLDBD-decay half-life for arbitrary mN for all the experimentally interesting isotopes without resorting to real nuclear structure calculations.

Amand Faessler; Marcela Gonzalez; Sergey Kovalenko; Fedor Simkovic

2014-08-26T23:59:59.000Z

55

Neutrino mass hierarchy from nuclear reactor experiments  

Science Journals Connector (OSTI)

Ten years from now reactor neutrino experiments will attempt to determine which neutrino mass eigenstate is the most massive. In this paper we present the results of more than seven million detailed simulations of such experiments, studying the dependence of the probability of successfully determining the mass hierarchy upon the analysis method, the neutrino mass matrix parameters, reactor flux models, geoneutrinos and, in particular, combinations of baselines. We show that a recently reported spurious dependence of the data analysis upon the high energy tail of the reactor spectrum can be removed by using a weighted Fourier transform. We determine the optimal baselines and corresponding detector locations. For most values of the CP-violating, leptonic Dirac phase ?, a degeneracy prevents NO?A and T2K from determining either ? or the hierarchy. We determine the confidence with which a reactor experiment can determine the hierarchy, breaking the degeneracy.

Emilio Ciuffoli; Jarah Evslin; Xinmin Zhang

2013-08-29T23:59:59.000Z

56

Testing solar lepton mixing sum rules in neutrino oscillation experiments  

E-Print Network (OSTI)

Small discrete family symmetries such as S4, A4 or A5 may lead to simple leading-order predictions for the neutrino mixing matrix such as the bimaximal, tribimaximal or golden ratio mixing patterns, which may be brought into agreement with experimental data with the help of corrections from the charged-lepton sector. Such scenarios generally lead to relations among the parameters of the physical leptonic mixing matrix known as solar lepton mixing sum rules. In this article, we present a simple derivation of such solar sum rules, valid for arbitrary neutrino and charged lepton mixing angles and phases, assuming only {\\theta}13^{\

Ballett, Peter; Luhn, Christoph; Pascoli, Silvia; Schmidt, Michael A

2014-01-01T23:59:59.000Z

57

Neutrinoless double beta decay and neutrino masses  

Science Journals Connector (OSTI)

Neutrinoless double beta decay (0???) is a promising test for lepton number violating physics beyond the standard model (SM) of particle physics. There is a deep connection between this decay and the phenomenon of neutrino masses. In particular we will discuss the relation between 0??? and Majorana neutrino masses provided by the so-called Schechter-Valle theorem in a quantitative way. Furthermore we will present an experimental cross check to discriminate 0??? from unknown nuclear background using only one isotope i.e. within one experiment.

Michael Duerr

2012-01-01T23:59:59.000Z

58

Unified Explanation of Quark and Lepton Masses and Mixings in the Supersymmetric SO(10) Model  

E-Print Network (OSTI)

We discussed neutrino masses and mixings in SUSY SO(10) model where quarks and leptons have Yukawa couplings to at least two 10 and one $\\bar{126}$ Higgs scalars. In this model, the Dirac and the right-handed Majorana mass terms are expressed by linear combinations of quark and charged lepton mass matrices, which then determine the neutrino mass matrix by the see-saw mechanism. We show that there are various solutions to reproduce a large mixing angle for $\

Kin-ya Oda; Eiichi Takasugi; Minoru Tanaka; Masaki Yoshimura

1998-08-06T23:59:59.000Z

59

Double Beta Decay, Majorana Neutrinos, and Neutrino Mass  

E-Print Network (OSTI)

The theoretical and experimental issues relevant to neutrinoless double-beta decay are reviewed. The impact that a direct observation of this exotic process would have on elementary particle physics, nuclear physics, astrophysics and cosmology is profound. Now that neutrinos are known to have mass and experiments are becoming more sensitive, even the non-observation of neutrinoless double-beta decay will be useful. If the process is actually observed, we will immediately learn much about the neutrino. The status and discovery potential of proposed experiments are reviewed in this context, with significant emphasis on proposals favored by recent panel reviews. The importance of and challenges in the calculation of nuclear matrix elements that govern the decay are considered in detail. The increasing sensitivity of experiments and improvements in nuclear theory make the future exciting for this field at the interface of nuclear and particle physics.

Frank T. Avignone III; Steven R. Elliott; Jonathan Engel

2007-08-07T23:59:59.000Z

60

Experiments for the absolute neutrino mass measurement  

E-Print Network (OSTI)

Experimental results and perspectives of different methods to measure the absolute mass scale of neutrinos are briefly reviewed. The mass sensitivities from cosmological observations, double beta decay searches and single beta decay spectroscopy differ in sensitivity and model dependance. Next generation experiments in the three fields reach the sensitivity for the lightest mass eigenstate of $m_1<0.2eV$, which will finally answer the question if neutrino mass eigenstates are degenerate. This sensitivity is also reached by the only model-independent approach of single beta decay (KATRIN experiment). For higher sensitivities on cost of model-dependance the neutrinoless double beta decay search and cosmological observation have to be applied. Here, in the next decade sensitivities are approached with the potential to test inverted hierarchy models.

Markus Steidl

2009-06-02T23:59:59.000Z

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61

Quark and lepton masses and mixing in the landscape  

E-Print Network (OSTI)

Even if quark and lepton masses are not uniquely predicted by the fundamental theory, as may be the case in the string theory landscape, nevertheless their pattern may reveal features of the underlying theory. We use statistical techniques to show that the observed masses appear to be representative of a scale invariant distribution, rho(m) ~ 1/m. If we extend this distribution to include all the Yukawa couplings, we show that the resulting CKM matrix elements typically show a hierarchical pattern similar to observations. The Jarlskog invariant measuring the amount of CP violation is also well reproduced in magnitude. We also apply this framework to neutrinos using the seesaw mechanism. The neutrino results are ambiguous, with the observed pattern being statistically allowed even though the framework does not provide a natural explanation for the observed two large mixing angles. Our framework highly favors a normal hierarchy of neutrino masses. We also are able to make statistical predictions in the neutrino sector when we specialize to situations consistent with the known mass differences and two large mixing angles. Within our framework, we show that with 95% confidence the presently unmeasured MNS mixing angle sin theta_{13} is larger than 0.04 and typically of order 0.1. The leptonic Jarlskog invariant is found to be typically of order 10^{-2} and the magnitude of the effective Majorana mass m_{ee} is typically of order 0.001 eV.

John F. Donoghue; Koushik Dutta; Andreas Ross

2006-01-27T23:59:59.000Z

62

Invisible Z decay width bounds on active-sterile neutrino mixing in the (3+1) and (3+2) models  

E-Print Network (OSTI)

In this work we consider the standard model extended with singlet sterile neutrinos with mass in the eV range and mixed with the active neutrinos. The active-sterile neutrino mixing renders new contributions to the invisible Z decay width which, in the case of light sterile neutrinos, depends on the active-sterile mixing matrix elements only. We then use the current experimental value of the invisible Z decay width to obtain bounds on these mixing matrix elements for both (3+1) and (3+2) models.

C. A. de S. Pires

2007-06-08T23:59:59.000Z

63

Arbitrary mass Majorana neutrinos in neutrinoless double beta decay  

Science Journals Connector (OSTI)

We revisit the mechanism of neutrinoless double beta (0???) decay mediated by the exchange with the heavy Majorana neutrino N of arbitrary mass mN, slightly mixed ?UeN with the electron neutrino ?e. By assuming the dominance of this mechanism, we update the well-known 0???-decay exclusion plot in the mN?UeN plane taking into account recent progress in the calculation of nuclear matrix elements within quasiparticle random phase approximation and improved experimental bounds on the 0???-decay half-life of Ge76 and Xe136. We also consider the known formula approximating the mN dependence of the 0???-decay nuclear matrix element in a simple explicit form. We analyze its accuracy and specify the corresponding parameters, allowing one to easily calculate the 0???-decay half-life for arbitrary mN for all the experimentally interesting isotopes without resorting to real nuclear structure calculations.

Amand Faessler; Marcela Gonzlez; Sergey Kovalenko; Fedor imkovic

2014-11-21T23:59:59.000Z

64

Colliding neutrino beams  

E-Print Network (OSTI)

From several neutrino oscillation experiments, we understand now that neutrinos have mass. However, we really don't know what mechanism is responsible for producing this neutrino mass. Current or planned neutrino experiments utilize neutrino beams and long-baseline detectors to explore flavor mixing but do not address the question of the origin of neutrino mass. In order to answer that question, neutrino interactions need to be explored at much higher energies. This paper outlines a program to explore neutrinos and their interactions with various particles through a series of experiments involving colliding neutrino beams.

Reinhard Schwienhorst

2007-11-08T23:59:59.000Z

65

Fermion Masses from Six Dimensions and Implications for Majorana Neutrinos  

E-Print Network (OSTI)

In these notes, we review the main results of our approach to fermion masses. The marge mass ratios between fermions, confronted with a unique breaking mechanism leading to vector bosons masses, led us to consider the possibility that they result from the overlap of fermion wave functions. Such overlaps vary indeed very strongly if the observed fermion families in 4 dimensions originate in a single family in 6 dimensions, through localized wave functions. This framework leads in a natural way to large mass ratios and small mixing angles between quarks. What came as a surprise is that if we impose that neutrinos behave as 2-component ("Majorana") particles in 4D, a completely different situation is obtained for them. Instead of diagonal mass matrices, anti-diagonal ones emerge and lead to a generic prediction of combined inverted hierarchy, large mixing angles in the leptonic sector, and a suppression of neutrinoless-double beta decay placing it at the lower limit of the inverted hierarchy branch, a challenging situation for on-going and planned experiments. Our approach predicted the size of the $\\theta_{13}$ mixing angle before its actual measurement. Possible signals at colliders are only briefly evoked.

J-M Frre; M Libanov; S Mollet; S Troitsky

2014-09-29T23:59:59.000Z

66

Geometric gravitational origin of neutrino oscillations and mass-energy  

E-Print Network (OSTI)

A mass-energy scale for neutrinos was calculated from the null cone curvature using geometric concepts. The scale is variable depending on the gravitational potential and the trajectory inclination with respect to the field direction. The proposed neutrino covariant equation provides the adequate curvature. The mass-energy at the Earth surface varies from a horizontal value 0.402 eV to a vertical value 0.569 eV. Earth spinor waves with winding numbers n show squared energy differences within ranges from 2.05 x 10*(-3) to 4.10 x 10*(-3) eV*2 for n=0,1 neutrinos and from 3.89 x 10*(-5) to 7.79 x 10*(-5) eV*2 for n=1,2 neutrinos. These waves interfere and the different phase velocities produce neutrino-like oscillations. The experimental results for atmospheric and solar neutrino oscillation mass parameters respectivelly fall within these theoretical ranges. Neutrinos in outer space, where interactions may be neglected, appear as particles travelling with zero mass on null geodesics. These gravitational curvature energies are consistent with neutrino oscillations, zero neutrino rest masses and Einstein's General Relativity and energy mass equivalence principle. When analyzing or averaging experimental neutrino mass-energy results of different experiments on the Earth it is of interest to consider the possible influence of the trajectory inclination angle.

Gustavo R. Gonzalez-Martin

2012-12-10T23:59:59.000Z

67

Testing varying neutrino mass with short gamma ray bursts  

Science Journals Connector (OSTI)

In this paper we study the possibility of probing for the absolute neutrino mass and its variation with short gamma ray burst (GRB). We have calculated the flight time difference between a massive neutrino and a photon in two different approaches to the mass varying neutrinos. Firstly we parametrize the neutrino mass as a function of the redshift in a model independent way, then we consider two specific models where the neutrino mass varies during the evolution of the quintessence fields. Our calculations show in general the value of the time delay is changed substantially relative to a constant neutrino mass and is also expected to be larger than the duration time of the short GRB.

Hong Li; Zigao Dai; Xinmin Zhang

2005-06-07T23:59:59.000Z

68

Strong thermal leptogenesis and the absolute neutrino mass scale  

E-Print Network (OSTI)

We show that successful strong thermal leptogenesis, where the final asymmetry is independent of the initial conditions and in particular a large pre-existing asymmetry is efficiently washed-out, favours values of the lightest neutrino mass $m_1 \\gtrsim 10\\,{\\rm meV}$ for normal ordering (NO) and $m_1 \\gtrsim 3\\,{\\rm meV}$ for inverted ordering (IO) for models with orthogonal matrix entries respecting $|\\Omega_{ij}^2| \\lesssim 2$. . We show analytically why lower values of $m_1$ require a high level of fine tuning in the seesaw formula and/or in the flavoured decay parameters (in the electronic for NO, in the muonic for IO). We also show how this constraint exists thanks to the measured values of the neutrino mixing angles and can be tighten by a future determination of the Dirac phase. Our analysis also allows to place more stringent constraint for a specific model or class of models, such as $SO(10)$-inspired models, and shows that some models cannot realise strong thermal leptogenesis for any value of $m_1$. A scatter plot analysis fully supports the analytical results. We also briefly discuss the interplay with absolute neutrino mass scale experiments concluding that they will be able in the coming years to either corner strong thermal leptogenesis or find positive signals pointing to a non-vanishing $m_1$. Since the constraint is much stronger for NO than for IO, it is very important that new data from planned neutrino oscillation experiments will be able to solve the ambiguity.

Pasquale Di Bari; Sophie E. King; Michele Re Fiorentin

2014-03-24T23:59:59.000Z

69

Generation of Small Neutrino Majorana Masses in a Randall-Sundrum Model  

E-Print Network (OSTI)

We propose a model, in the framework of 5D with warped geometry, in which small neutrino Majorana masses are generated by tree level coupling of lepton doublets to a SU(2)_{L}-triplet scalar field, which is coupled to a bulk SM-singlet. The neutrino mass scale is determined by the bulk mass term (alpha_{S}) of the singlet as ve^{-2(alpha_{S}-1)*pi*kR}. This suppression is due to a small overlap between the profile of the singlet zero mode and the triplet, which is confined to the TeV brane. The generic form for the neutrino mass matrix due to the overlap between the fermions is not compatible with the LMA solution. This is overcome by imposing a Z_{4} symmetry, which is softly broken by couplings of the triplet Higgs to the lepton doublets. This model successfully reproduces the observed masses and mixing angles in charged lepton sector as well as in the neutrino sector, in addition to having a prediction of |U_{e3}| ~ O(0.01). The mass of the triplet is of the order of a TeV, and could be produced at upcoming collider experiments. The doubly charged member of the triplet can decay into two same sign charged leptons yielding the whole triplet coupling matrix which, in turn, gives the mixing matrix in the neutrino sector.

Mu-Chun Chen

2005-04-18T23:59:59.000Z

70

Connecting Leptonic CP Violation, Lightest Neutrino Mass and Baryon Asymmetry Through Type II Seesaw  

E-Print Network (OSTI)

We study the possibility of connecting leptonic Dirac CP phase $\\delta$, lightest neutrino mass and baryon asymmetry of the Universe within the framework of a model where both type I and type II seesaw mechanisms contribute to neutrino mass. Type I seesaw gives rise to Tri-Bimaximal (TBM) type neutrino mixing whereas type II seesaw acts as a correction in order to generate non-zero $\\theta_{13}$. We derive the most general form of type II seesaw mass matrix which can not only give rise to correct neutrino mixing angles but also can generate non-trivial value of $\\delta$. Considering both the cases where type II seesaw is sub-leading and is equally dominant compared to type I seesaw, we correlate the type II seesaw term with $\\delta$ and lightest neutrino mass. We further constrain the Dirac CP phase $\\delta$ and hence the type II seesaw mass matrix from the requirement of producing the observed baryon asymmetry through the mechanism of leptogenesis.

Kalita, Rupam

2014-01-01T23:59:59.000Z

71

Neutrino masses from R-parity violation with a Z3 symmetry  

Science Journals Connector (OSTI)

We consider a supersymmetric model where the neutrino mass matrix arises from bilinear and trilinear R-parity violation, both restricted by a Z3 flavor symmetry. Assuming flavor-blind soft supersymmetry breaking conditions, corrected at low energies due to running effects, we obtain a neutrino mass matrix in agreement with oscillation data. In particular, a large ?13 angle can be easily accommodated. We also find a correlation between the reactor and atmospheric mixing angles. This leads in some scenarios to a clear deviation from ?23=?/4. The lightest supersymmetric particle decay, dominated by the trilinear couplings, provides a direct way to test the model at colliders.

E. Peinado and A. Vicente

2012-11-27T23:59:59.000Z

72

Perspectives on Unification in View of Neutrino Mass  

Science Journals Connector (OSTI)

......neutrino and KamLand observations. We do not know the absolute value of the masses but for Majorana neutrinos, neutrinoless double beta decay experiments tell us that i U2 imi 1 eV (roughly) and from cosmology (WMAP), one finds also a similar......

Rabindra N. Mohapatra

2007-02-01T23:59:59.000Z

73

Constraining four neutrino mass patterns from neutrinoless double beta decay  

E-Print Network (OSTI)

All existing data on neutrino oscillations (including those from the LSND experiment) imply a four neutrino scheme with six different allowed mass patterns. Some of the latter are shown to be disfavored by using a conservative upper bound on the $\\beta beta 0 \

Sandip Pakvasa; Probir Roy

2002-03-19T23:59:59.000Z

74

Technique for Direct eV-Scale Measurements of the Mu and Tau Neutrino Masses Using Supernova Neutrinos  

E-Print Network (OSTI)

Early black hole formation in a core-collapse supernova will abruptly truncate the neutrino fluxes. The sharp cutoff can be used to make model-independent time-of-flight neutrino mass tests. Assuming a neutrino luminosity of $10^{52}$ erg/s per flavor at cutoff and a distance of 10 kpc, SuperKamiokande can detect an electron neutrino mass as small as 1.8 eV, and the proposed OMNIS detector can detect mu and tau neutrino masses as small as 6 eV. This {\\it Letter} presents the first technique with direct sensitivity to eV-scale mu and tau neutrino masses.

J. F. Beacom; R. N. Boyd; A. Mezzacappa

2000-06-01T23:59:59.000Z

75

Higgs boson Mass in GMSB with MessengerMatter mixing  

Science Journals Connector (OSTI)

A Higgs-like particle with mass of order 125 GeV has been observed by both ATLAS and CMS experiments. This Higgs mass causes sparticle masses in the several to multi-TeV range in the simple version of minimal GMSB models. We consider the effects of messengermatter mixing on the lightest CPeven Higgs boson mass in gaugemediated supersymmetry breaking models. We find with such mixings a 125 GeV Higgs boson can be naturally obtained even with a subTeV SUSY spectrum, and when the gravitino has a cosmologically preferred subkeV mass. In addition, when these models are embedded into a grand unification framework with a U ( 1 ) flavor symmetry they explain the fermion mass hierarchy and generate naturally large neutrino mixing angles accompanied with small quark mixing angles. While SUSY mediated flavor changing processes are sufficiently suppressed in such an embedding, it can resolve the apparent discrepancy in the CP asymmetry parameters sin 2 ? and ? K , and it predicts an observable ? ? e ? decay rate.

Abdelhamid Albaid

2012-01-01T23:59:59.000Z

76

Effective Neutrino Mass Operators: A Guide to Model Building  

E-Print Network (OSTI)

Effective operators relevant for generating small Majorana masses for the neutrinos in the Standard Model will be considered. These operators serve as a useful guide for building models of neutrino mass. Some of these operators are represented by familiar models in the literature, and others lead to interesting new models. The number of relevant operators will be drastically reduced if neutrinoless double beta decays are observed in current experiments.

C. N. Leung

2001-08-15T23:59:59.000Z

77

Neutrino mass spectrum and neutrinoless double beta decay  

E-Print Network (OSTI)

The relations between the effective Majorana mass of the electron neutrino, $m_{ee}$, responsible for neutrinoless double beta decay, and the neutrino oscillation parameters are considered. We show that for any specific oscillation pattern $m_{ee}$ can take any value (from zero to the existing upper bound) for normal mass hierarchy and it can have a minimum for inverse hierarchy. This means that oscillation experiments cannot fix in general $m_{ee}$. Mass ranges for $m_{ee}$ can be predicted in terms of oscillation parameters with additional assumptions about the level of degeneracy and the type of hierarchy of the neutrino mass spectrum. These predictions for $m_{ee}$ are systematically studied in the specific schemes of neutrino mass and flavor which explain the solar and atmospheric neutrino data. The contributions from individual mass eigenstates in terms of oscillation parameters have been quantified. We study the dependence of $m_{ee}$ on the non-oscillation parameters: the overall scale of the neutrino mass and the relative mass phases. We analyze how forthcoming oscillation experiments will improve the predictions for $m_{ee}$. On the basis of these studies we evaluate the discovery potential of future \\znbb decay searches. The role \\znbb decay searches will play in the reconstruction of the neutrino mass spectrum is clarified. The key scales of $m_{ee}$, which will lead to the discrimination among various schemes are: $m_{ee} \\sim 0.1$ eV and $m_{ee} \\sim 0.005$ eV.

H. V. Klapdor-Kleingrothaus; H. Ps; A. Y. Smirnov

2000-10-08T23:59:59.000Z

78

Neutrino diffusion and mass ejection in protoneutron stars  

SciTech Connect

We discuss the mass ejection mechanism induced by diffusion of neutrino during the early stage of the protoneutron star cooling. A dynamical calculation is employed in order to determine the amount of matter ejected and the remnant compact object mass. An equation of state considering hadronic and quark phases for the stellar dense matter was used to solve the whole time evolution of the system during the cooling phase. The initial neutrino population was obtained by considering beta equilibrium in the dense stellar matter with confined neutrinos, in the very early period of the deleptonic stage of the nascent pulsar. For specified initial configurations of the protoneutron star, we solve numerically the set of equations of motion together with neutrino diffusion through the dense stellar medium.

Almeida, L. G. [Universidade Federal do Acre-Campus Floresta, Estrada do Canela Fina, km 12, 69980-000, Cruzeiro do Sul, AC (Brazil); Centro Brasileiro de Pesquisas Fisicas, Rua Dr. Xavier Sigaud 150, 22290-180, Rio de Janeiro, RJ (Brazil); Rodrigues, H.; Portes, D. Jr. [Centro Federal de Educacao Tecnologica do Rio de Janeiro, Av. Maracana 249, 20271-110, Rio de Janeiro, RJ (Brazil); Duarte, S. B. [Centro Brasileiro de Pesquisas Fisicas, Rua Dr. Xavier Sigaud 150, 22290-180, Rio de Janeiro, RJ (Brazil)

2010-11-15T23:59:59.000Z

79

A new method for measuring the absolute neutrino mass  

E-Print Network (OSTI)

The probability of the event that a neutrino produced in pion decay is detected in the intermediate $T$ shorter than the life-time $\\tau_{\\pi}$, $T \\leq \\tau_{\\pi}$, is sensitive to the absolute mass of the neutrino. With a newly formulated S-matrix $S[T]$ that satisfies the boundary conditions of the experiments at a finite $T$, the rate of the event is computed as $\\Gamma_0+\\tilde{g}(\\omega_{\

Kenzo Ishikawa; Yutaka Tobita

2012-09-25T23:59:59.000Z

80

Loop-induced Neutrino Masses: A Case Study  

E-Print Network (OSTI)

We study the cocktail model in which the Majorana neutrino masses are generated by the so-called "cocktail" three-loop diagrams with the dark matter particle running in the loops. In particular, we give the correct analytic expressions of the neutrino masses in the model by the detailed calculation of the cocktail diagrams. Based on the reliable numerical calculation of the loop integrals, we explore the parameter space which can give the correct orders of neutrino masses while satisfying other experimental constraints, such as those from the neutrinoless double beta decay, low-energy lepton flavor violation processes, electroweak precision tests, and collider searches. As a result, the large couplings and the large mass difference between the two singly-charged (neutral) scalars are required.

Geng, Chao-Qiang; Tsai, Lu-Hsing

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "neutrino mass mixing" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Neutrino Mass and Dark Energy from Weak Lensing  

Science Journals Connector (OSTI)

Weak gravitational lensing of background galaxies by intervening matter directly probes the mass distribution in the Universe. This distribution is sensitive to both the dark energy and neutrino mass. We examine the potential of lensing experiments to measure features of both simultaneously. Focusing on the radial information contained in a future deep 4000??deg2 survey, we find that the expected (1-?) error on a neutrino mass is 0.1eV, if the dark-energy parameters are allowed to vary. The constraints on dark-energy parameters are similarly restrictive, with errors on w of 0.09.

Kevork N. Abazajian and Scott Dodelson

2003-07-24T23:59:59.000Z

82

Decay Oscillations in Electron Capture and the Neutrino Mass Difference  

E-Print Network (OSTI)

Quantum mechanical theory disallows the model that has been used to infer the neutrino mass difference from the reported "GSI oscillations" in the rates of decay of hydrogen-like ions by electron capture. It has not been proved that the existence of mass-difference-dependent oscillations conflicts with quantum mechanics but no consistent quantum mechanical model has been shown to predict them.

Murray Peshkin

2014-03-17T23:59:59.000Z

83

The Neutrino Mass Hierarchy from Nuclear Reactor Experiments  

E-Print Network (OSTI)

10 years from now reactor neutrino experiments will attempt to determine which neutrino mass eigenstate is the most massive. In this letter we present the results of more than seven million detailed simulations of such experiments, studying the dependence of the probability of successfully determining the mass hierarchy upon the analysis method, the neutrino mass matrix parameters, reactor flux models, geoneutrinos and, in particular, combinations of baselines. We show that a recently reported spurious dependence of the data analysis upon the high energy tail of the reactor spectrum can be removed by using a weighted Fourier transform. We determine the optimal baselines and corresponding detector locations. For most values of the CP-violating, leptonic Dirac phase delta, a degeneracy prevents NOvA and T2K from determining either delta or the hierarchy. We determine the confidence with which a reactor experiment can determine the hierarchy, breaking the degeneracy.

Emilio Ciuffoli; Jarah Evslin; Xinmin Zhang

2013-02-04T23:59:59.000Z

84

Testing Radiative Neutrino Mass Models at the LHC  

E-Print Network (OSTI)

The Large Hadron Collider provides us new opportunities to search for the origin of neutrino mass. Beyond the minimal see-saw models a plethora of models exist which realise neutrino mass at tree- or loop-level, and it is important to be sure that these possibilities are satisfactorily covered by searches. The purpose of this paper is to advance a systematic approach to this problem. Majorana neutrino mass models can be organised by SM-gauge-invariant operators which violate lepton number by two units. In this paper we write down the minimal ultraviolet completions for all of the mass-dimension 7 operators. We predict vector-like quarks, vector-like leptons, scalar leptoquarks, a charged scalar, and a scalar doublet, whose properties are constrained by neutrino oscillation data. A detailed collider study is presented for $O_3=LLQ\\bar dH$ and $O_8 = L\\bar d\\bar e^\\dagger \\bar u^\\dagger H$ completions with a vector-like quark $\\chi\\sim(3, 2, -\\frac{5}{6})$ and a leptoquark $\\phi\\sim(\\bar 3,1,\\frac{1}{3})$. The existing LHC limits extracted from searches for vector-like fermions and sbottoms/stops are $m_\\chi \\gtrsim 620$ GeV and $m_\\phi\\gtrsim 600$ GeV.

Yi Cai; Jackson D. Clarke; Michael A. Schmidt; Raymond R. Volkas

2014-10-22T23:59:59.000Z

85

E-Print Network 3.0 - active-sterile neutrino mixing Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

Collection: Physics 4 arXiv:hep-ph0608147v113Aug2006 NUHEP-TH06-06 Neutrino Phenomenology of Very Low-Energy Seesaws Summary: , related via the standard lepton mixing...

86

Ultra-low Q values for neutrino mass measurements  

SciTech Connect

We investigate weak nuclear decays with extremely small kinetic energy release (Q value) and thus extremely good sensitivity to the absolute neutrino mass scale. In particular, we consider decays into excited daughter states, and we show that partial ionization of the parent atom can help to tune Q values to << 1 keV. We discuss several candidate isotopes undergoing {beta}{sup {+-}}, bound state {beta}, or electron capture decay, and come to the conclusion that a neutrino mass measurement using low-Q decays might only be feasible if no ionization is required, and if future improvements in isotope production technology, nuclear mass spectroscopy, and atomic structure calculations are possible. Experiments using ions, however, are extremely challenging due to the large number of ions that must be stored. New precision data on nuclear excitation levels could help to identify further isotopes with low-Q decay modes and possibly less challenging requirements.

Kopp, Joachim; /Heidelberg, Max Planck Inst. /Fermilab; Merle, Alexander; /Heidelberg, Max Planck Inst.

2009-11-01T23:59:59.000Z

87

Neutrino mass hierarchy determination with IceCube-PINGU  

Science Journals Connector (OSTI)

We discuss the neutrino mass hierarchy determination with atmospheric neutrinos in Precision IceCube Next Generation Upgrade, based on a simulation with the GLoBES software including the full three flavor framework and parameter degeneracy, and we compare it to long-baseline experiment options. We demonstrate that the atmospheric mass hierarchy sensitivity depends on the achievable experiment properties, and we identify the main targets for optimization, whereas the impact of a large number of tested systematical errors turns out to be small. Depending on the values of ?23, ?, and the true hierarchy, a 90%C.L. to 3? discovery after three years of operation seems conceivable. We also emphasize the synergy with existing beam and reactor experiments, driven by NO?A, such as the complementary coverage of the parameter space. Finally, we point out that a low intensity neutrino beam with a relatively short decay pipe could be used to determine the mass hierarchy with a sensitivity comparable to the LBNE experiment irrespective of the directional resolution of the detector.

Walter Winter

2013-07-22T23:59:59.000Z

88

Searches for New Physics at MiniBooNE: Sterile Neutrinos and Mixing Freedom  

SciTech Connect

The MiniBooNE experiment was designed to perform a search for {nu}{sub {mu}} {yields} {nu}{sub e} oscillations in a region of {Delta}m{sup 2} and sin{sup 2} 2{theta} very different from that allowed by standard, three-neutrino oscillations, as determined by solar and atmospheric neutrino experiments. This search was motivated by the LSND experimental observation of an excess of {bar {nu}}{sub e} events in a {bar {nu}}{sub {mu}} beam which was found compatible with two-neutrino oscillations at {Delta}m{sup 2} {approx} 1 eV{sup 2} and sin{sup 2} 2{theta} < 1%. If confirmed, such oscillation signature could be attributed to the existence of a light, mostly-sterile neutrino, containing small admixtures of weak neutrino eigenstates. In addition to a search for {nu}{sub {mu}} {yields} {nu}{sub e} oscillations, MiniBooNE has also performed a search for {bar {nu}}{sub {mu}} {yields} {bar {nu}}{sub e} oscillations, which provides a test of the LSND two-neutrino oscillation interpretation that is independent of CP or CPT violation assumptions. This dissertation presents the MiniBooNE {nu}{sub {mu}} {yields} {nu}{sub e} and {bar {nu}}{sub {mu}} {yields} {bar {nu}}{sub e} analyses and results, with emphasis on the latter. While the neutrino search excludes the two-neutrino oscillation interpretation of LSND at 98% C.L., the antineutrino search shows an excess of events which is in agreement with the two-neutrino {bar {nu}}{sub {mu}} {yields} {bar {nu}}{sub e} oscillation interpretation of LSND, and excludes the no oscillations hypothesis at 96% C.L. Even though the neutrino and antineutrino oscillation results from MiniBooNE disagree under the single sterile neutrino oscillation hypothesis, a simple extension to the model to include additional sterile neutrino states and the possibility of CP violation allows for differences between neutrino and antineutrino oscillation signatures. In view of that, the viability of oscillation models with one or two sterile neutrinos is investigated in global fits to MiniBooNE and LSND data, with and without constraints from other oscillation experiments with similar sensitivities to those models. A general search for new physics scenarios which would lead to effective non-unitarity of the standard 3 x 3 neutrino mixing matrix, or mixing freedom, is also performed using neutrino and antineutrino data available from MiniBooNE.

Karagiorgi, Georgia S.; /MIT

2010-07-01T23:59:59.000Z

89

Neutrino democracy, fermion mass hierarchies, and proton decay from 5D SU(5)  

Science Journals Connector (OSTI)

The explanation of various observed phenomena such as large angle neutrino oscillations, hierarchies of charged fermion masses and CKM mixings, and apparent baryon number conservation may have a common origin. We show how this could occur in 5D SUSY SU(5) supplemented by a U(1) flavor symmetry and additional matter supermultiplets called copies. In addition, the proton decays into p?K?, with an estimated lifetime of the order of 1033-1036 yr. Other decay channels include Ke and K? with comparable rates. We also expect that BR(??e?)?BR(????).

Qaisar Shafi and Zurab Tavartkiladze

2003-04-11T23:59:59.000Z

90

Los Alamos Science, Number 25 -- 1997: Celebrating the Neutrino  

DOE R&D Accomplishments (OSTI)

This issue is devoted to the neutrino and its remaining mysteries. It is divided into the following areas: (1) The Reines-Cowan experiment -- detecting the poltergeist; (2) The oscillating neutrino -- an introduction to neutrino masses and mixing; (3) A brief history of neutrino experiments at LAMPF; (4) A thousand eyes -- the story of LSND (Los Alamos neutrino oscillation experiment); (5) The evidence for oscillations; (6) The nature of neutrinos in muon decay and physics beyond the Standard Model; (7) Exorcising ghosts -- in pursuit of the missing solar neutrinos; (8) MSW -- a possible solution to the solar neutrino problem; (8) Neutrinos and supernovae; and (9) Dark matter and massive neutrinos.

Cooper, N. G. [ed.

1997-00-00T23:59:59.000Z

91

INTRODUCTION TO THREE-NEUTRINO MIXING PARAMETERS LISTINGS  

E-Print Network (OSTI)

currently use this convention. Accelerator neutrino experiments: Ignoring the small m2 21 scale, CP;­ 2­ accelerator oscillation experiment are: P( ) = sin2 (223) cos4 (13) sin2 (m2 32L/4E) (3) P( e scale, the equation for neutrino oscillation in vacuum is: P( e) = P1 + P2 + P3 + P4 P1 = sin2 (23) sin

92

Model-independent Constraint on the Neutrino Mass Spectrum from the Neutrinoless Double Beta Decay  

E-Print Network (OSTI)

We present a concise formula to relate the effective mass term of the neutrinoless double beta decay to a single neutrino mass, two Majorana CP-violating phases and four observables of neutrino oscillations for a generic neutrino mass spectrum. If the alleged evidence for the neutrinoless double beta decay is taken into account, one may obtain a rough but model-independent constraint on the absolute scale of neutrino masses -- it is most likely to be in the range between 0.1 eV and 1 eV.

Zhi-zhong Xing

2002-02-05T23:59:59.000Z

93

Majorana Neutrino Masses from Neutrinoless Double Beta Decay and Cosmology  

E-Print Network (OSTI)

When three Majorana neutrinos describe the solar and atmospheric neutrino data via oscillations, a nonzero measurement of neutrinoless double beta ($0\

V. Barger; K. Whisnant

1999-04-08T23:59:59.000Z

94

Phenomenology Of Sterile Neutrinos At Different Mass Scales: Neutrinoless Double Beta Decay And Neutrino Oscillations.  

E-Print Network (OSTI)

??The existence of neutrino oscillation is the first evidence of physics beyond the Standard Model. It proves that neutrinos are massive and motivates the study (more)

WONG, CHAN,FAI

2012-01-01T23:59:59.000Z

95

Neutrino fluxes from nonuniversal Higgs mass LSP annihilations in the Sun  

SciTech Connect

We extend our previous studies of the neutrino fluxes expected from neutralino LSP annihilations inside the Sun to include variants of the minimal supersymmetric extension of the Standard Model (MSSM) with squark, slepton and gaugino masses constrained to be universal at the GUT scale, but allowing one or two nonuniversal supersymmetry breaking parameters contributing to the Higgs masses (NUHM1,2). As in the constrained MSSM (CMSSM) with universal Higgs masses, there are large regions of the NUHM parameter space where the LSP density inside the Sun is not in equilibrium, so that the annihilation rate may be far below the capture rate, and there are also large regions where the capture rate is not dominated by spin-dependent LSP-proton scattering. The spectra possible in the NUHM are qualitatively similar to those in the CMSSM. We calculate neutrino-induced muon fluxes above a threshold energy of 10 GeV, appropriate for the IceCube/DeepCore detector, for points where the NUHM yields the correct cosmological relic density for representative choices of the NUHM parameters. We find that the IceCube/DeepCore detector can probe regions of the NUHM parameter space in addition to analogues of the focus point strip and the tip of the coannihilation strip familiar from the CMSSM. These include regions with enhanced Higgsino-gaugino mixing in the LSP composition, that occurs where neutralino mass eigenstates cross over. On the other hand, rapid-annihilation funnel regions in general yield neutrino fluxes that are unobservably small.

Ellis, John [TH Division, Physics Department, CERN, 1211 Geneva 23, Switzerland and Theoretical Physics and Cosmology Group, Department of Physics, King's College London, London WC2R 2LS (United Kingdom); Olive, Keith A. [William I. Fine Theoretical Physics Institute, School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455 (United States) and Department of Physics and SLAC, Stanford University, Palo Alto, California 94305 (United States); Savage, Christopher [Oskar Klein Centre for Cosmoparticle Physics, Department of Physics, Stockholm University, AlbaNova, SE-10691 Stockholm (Sweden); Spanos, Vassilis C. [Institute of Nuclear Physics, NCSR 'Demokritos', GR-15310 Athens (Greece)

2011-04-15T23:59:59.000Z

96

Scotogenic $Z_2$ or $U(1)_D$ Model of Neutrino Mass with $\\Delta(27)$ Symmetry  

E-Print Network (OSTI)

The scotogenic model of radiative neutrino mass with $Z_2$ or $U(1)_D$ dark matter is shown to accommodate $\\Delta(27)$ symmetry naturally. The resulting neutrino mass matrix is identical to either of two forms, one proposed in 2006, the other in 2008. These two structures are studied in the context of present neutrino data, with predictions of $CP$ violation and neutrinoless double beta decay.

Ma, Ernest

2014-01-01T23:59:59.000Z

97

Light neutrino mass spectrum with one or two right-handed singlet fermions added  

E-Print Network (OSTI)

We analyse two cases of the minimal extension of the Standard Model when one or two right-handed fields are added to the three left-handed fields. A second Higgs doublet (two Higgs doublet model - 2HDM) is included in our model. We calculate one-loop radiative corrections to the mass parameters which produce mass terms for the neutral leptons. In both cases we numerically analyse light neutrino masses as functions of the heavy neutrino masses. Parameters of the model are varied to find light neutrino masses that are compatible with experimental data of solar and atmospheric neutrino mass differences for normal hierarchy. We choose values for the parameters of the tree-level by numerical scans, where we look for the best agreement between computed and experimental neutrino oscillation angles.

Darius Jurciukonis; Thomas Gajdosik; Andrius Juodagalvis

2014-10-16T23:59:59.000Z

98

INTRODUCTION TO THREE-NEUTRINO MIXING PARAMETERS LISTINGS  

E-Print Network (OSTI)

(ANL). Introduction and Notation: With the exception of the LSND anomaly, current accelerator, reactor currently use this convention. Accelerator neutrino experiments: Ignoring the small m2 21 scale, CP violation, and matter effects, the equations for the probability of appearance in an accelerator oscillation

99

Results from Neutrino Oscillations Experiments  

SciTech Connect

The interpretation of the results of early solar and atmospheric neutrino experiments in terms of neutrino oscillations has been verified by several recent experiments using both, natural and man-made sources. The observations provide compelling evidence in favor of the existence of neutrino masses and mixings. These proceedings give a general description of the results from neutrino oscillation experiments, the current status of the field, and some possible future developments.

Aguilar-Arevalo, Alexis [Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico, Apartado Postal 70-543, Mexico, D.F., 04510 (Mexico)

2010-09-10T23:59:59.000Z

100

Iodine molecule for neutrino mass spectroscopy: ab initio calculation of spectral rate  

Science Journals Connector (OSTI)

......such as tritium for the measurement of an averaged absolute neutrino mass value, and (2) the search of neutrinoless double beta decay for verification of lepton number violation related to a finite Majorana type of masses. So far negative......

Motomichi Tashiro; Masahiro Ehara; Susumu Kuma; Yuki Miyamoto; Noboru Sasao; Satoshi Uetake; Motohiko Yoshimura

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "neutrino mass mixing" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Neutrinoless double beta decay in four-neutrino models  

E-Print Network (OSTI)

The most stringent constraint on the so-called effective electron neutrino mass from the present neutrinoless double beta decay experiments is |M_{ee}| < 0.2 eV, while the planned next generation experiment GENIUS is anticipated to reach a considerably more stringent limit |M_{ee}|< 0.001 eV. We investigate the constraints these bounds set on the neutrino masses and mixings of neutrinos in four-neutrino models where there exists a sterile neutrino along with the three ordinary neutrinos. We find that the GENIUS experiment would be sensitive to the electron neutrino masses down to the limit m_{\

Anna Kalliomaki; Jukka Maalampi

2000-03-29T23:59:59.000Z

102

Left-right models with light neutrino mass prediction and dominant neutrinoless double beta decay rate  

E-Print Network (OSTI)

In TeV scale left-right symmetric models, new dominant predictions to neutrinoless double beta decay and light neutrino masses are in mutual contradiction because of large contribution to the latter through popular seesaw mechanisms. We show that in a class of left-right models with high-scale parity restoration, these results coexist without any contravention with neutrino oscillation data and the relevant formula for light neutrino masses is obtained via gauged inverse seesaw mechanism. The most dominant contribution to the double beta decay is shown to be via $W^-_L- W^-_R$ mediation involving both light and heavy neutrino exchanges, and the model predictions are found to discriminate whether the Dirac neutrino mass is of quark-lepton symmetric origin or without it. We also discuss associated lepton flavor violating decays.

M. K. Parida; Sudhanwa Patra

2013-01-14T23:59:59.000Z

103

Neutrino mass matrices with a texture zero and a vanishing minor  

Science Journals Connector (OSTI)

We study the implications of the simultaneous existence of a texture zero and a vanishing minor in the neutrino mass matrix. There are 36 possible texture structures of this type, 21 of which reduce to two texture zero cases which have, already, been extensively studied. Of the remaining 15 textures only six are allowed by the current data. We examine the phenomenological implications of the allowed texture structures for Majorana type CP-violating phases, 1-3 mixing angle, and Dirac type CP-violating phase. All these possible textures can be generated through the seesaw mechanism and realized in the framework of discrete Abelian flavor symmetry. We present the symmetry realization of these texture structures.

S. Dev; Surender Verma; Shivani Gupta; R. R. Gautam

2010-03-31T23:59:59.000Z

104

Can neutrino mass be measured in low-energy electron capture decay?  

E-Print Network (OSTI)

The standard kinematic method for determining neutrino mass from the beta decay of tritium or other isotope is to measure the shape of the electron spectrum near the endpoint. It has been known for 30 years that a similar distortion of the "visible energy" remaining after electron capture is caused by neutrino mass. There has been a resurgence of interest in using this method with 163-Ho. Recent theoretical analyses offer reassurance that there are no significant theoretical uncertainties. We show that the situation is, however, more complicated, and that the spectrum shape is presently not well enough understood to permit a sensitive determination of the neutrino mass in this way.

Robertson, R G H

2014-01-01T23:59:59.000Z

105

Neutrino Oscillations, Neutrinoless Double Beta Decay  

Science Journals Connector (OSTI)

We review the experimental evidence for neutrino mixing and neutrino mass. Searches for possible branches into heavy neutrinos do not reveal evidence for static mixing with branching ratios larger than 10?4 to 10?6. Similarly neutrino oscillation experiments show no evidence for dynamic mixing in various oscillation channels. Stringent limits for ? e disappearance from a recent reactor experiment are presented. Results from neutrinoless double beta decay provide sensitive test for Majorana mass and right?hand couplings the present limits being 310 eV and 10?5 respectively.

F. Boehm

1982-01-01T23:59:59.000Z

106

Improved measurements of the neutrino mixing angle $?_{13}$ with the Double Chooz detector  

E-Print Network (OSTI)

The Double Chooz experiment presents improved measurements of the neutrino mixing angle $\\theta_{13}$ using the data collected in 467.90 live days from a detector positioned at an average distance of 1050 m from two reactor cores at the Chooz nuclear power plant. Several novel techniques have been developed to achieve significant reductions of the backgrounds and systematic uncertainties with respect to previous publications, whereas the efficiency of the $\\bar\

Y. Abe; J. C. dos Anjos; J. C. Barriere; E. Baussan; I. Bekman; M. Bergevin; T. J. C. Bezerra; L. Bezrukov; E. Blucher; C. Buck; J. Busenitz; A. Cabrera; E. Caden; L. Camilleri; R. Carr; M. Cerrada; P. -J. Chang; E. Chauveau; P. Chimenti; A. P. Collin; E. Conover; J. M. Conrad; J. I. Crespo-Anadn; K. Crum; A. S. Cucoanes; E. Damon; J. V. Dawson; J. Dhooghe; D. Dietrich; Z. Djurcic; M. Dracos; M. Elnimr; A. Etenko; M. Fallot; F. von Feilitzsch; J. Felde; S. M. Fernandes; V. Fischer; D. Franco; M. Franke; H. Furuta; I. Gil-Botella; L. Giot; M. Gger-Neff; L. F. G. Gonzalez; L. Goodenough; M. C. Goodman; C. Grant; N. Haag; T. Hara; J. Haser; M. Hofmann; G. A. Horton-Smith; A. Hourlier; M. Ishitsuka; J. Jochum; C. Jollet; F. Kaether; L. N. Kalousis; Y. Kamyshkov; D. M. Kaplan; T. Kawasaki; E. Kemp; H. de Kerret; D. Kryn; M. Kuze; T. Lachenmaier; C. E. Lane; T. Lasserre; A. Letourneau; D. Lhuillier; H. P. Lima Jr; M. Lindner; J. M. Lpez-Castao; J. M. LoSecco; B. Lubsandorzhiev; S. Lucht; J. Maeda; C. Mariani; J. Maricic; J. Martino; T. Matsubara; G. Mention; A. Meregaglia; T. Miletic; R. Milincic; A. Minotti; Y. Nagasaka; Y. Nikitenko; P. Novella; L. Oberauer; M. Obolensky; A. Onillon; A. Osborn; C. Palomares; I. M. Pepe; S. Perasso; P. Pfahler; A. Porta; G. Pronost; J. Reichenbacher; B. Reinhold; M. Rhling; R. Roncin; S. Roth; B. Rybolt; Y. Sakamoto; R. Santorelli; A. C. Schilithz; S. Schnert; S. Schoppmann; M. H. Shaevitz; R. Sharankova; S. Shimojima; D. Shrestha; V. Sibille; V. Sinev; M. Skorokhvatov; E. Smith; J. Spitz; A. Stahl; I. Stancu; L. F. F. Stokes; M. Strait; A. Stken; F. Suekane; S. Sukhotin; T. Sumiyoshi; Y. Sun; R. Svoboda; K. Terao; A. Tonazzo; H. H. Trinh Thi; G. Valdiviesso; N. Vassilopoulos; C. Veyssiere; M. Vivier; S. Wagner; N. Walsh; H. Watanabe; C. Wiebusch; L. Winslow; M. Wurm; G. Yang; F. Yermia; V. Zimmer

2014-06-30T23:59:59.000Z

107

Neutrino Oscillations from String Theory  

E-Print Network (OSTI)

We derive the character of neutrino oscillations that results from a model of equivalence principle violation suggested recently by Damour and Polyakov as a plausible consequence of string theory. In this model neutrino oscillations will take place through interaction with a long range scalar field of gravitational origin even if the neutrinos are degenerate in mass. The energy dependence of the oscillation length is identical to that in the conventional mass mixing mechanism. This possibility further highlghts the independence of and need for more exacting direct neutrino mass measurements together with a next generation of neutrinoless double beta decay experiments.

A. Halprin; C. N. Leung

1997-07-21T23:59:59.000Z

108

Neutrino Physics: A Selective Overview  

E-Print Network (OSTI)

Neutrinos in the Standard Model of particle physics are massless, neutral fermions that seemingly do little more than conserve 4-momentum, angular momentum, lepton number, and lepton flavour in weak interactions. In the last decade conclusive evidence has demonstrated that the Standard Model's description of neutrinos does not match reality. We now know that neutrinos undergo flavour oscillations, violating lepton flavour conservation and implying that neutrinos have non-zero mass. A rich oscillation phenomenology then becomes possible, including matter-enhanced oscillation and possibly CP violation in the neutrino sector. Extending the Standard Model to include neutrino masses requires the addition of new fields and mass terms, and possibly new methods of mass generation. In this review article I will discuss the evidence that has established the existence of neutrino oscillation, and then highlight unresolved issues in neutrino physics, such as the nature of three-generational mixing (including CP-violating effects), the origins of neutrino mass, the possible existence of light sterile neutrinos, and the difficult question of measuring the absolute mass scale of neutrinos.

Scott M. Oser

2006-04-11T23:59:59.000Z

109

Exotic Solutions to the Solar Neutrino Problem and Some Implications for Low Energy Solar Neutrino Experiments  

E-Print Network (OSTI)

In this talk, I review, from the phenomenological point of view, solutions to the solar neutrino problem, which are not provided by the conventional neutrino oscillation induced by mass and flavor mixing, and show that they can provide a good fit to the observed data. I also consider some simple implications for low energy solar neutrino experiments.

H. Nunokawa

2001-05-03T23:59:59.000Z

110

Neutrinos  

NLE Websites -- All DOE Office Websites (Extended Search)

source. Keywords: Neutrino, Oscillations, MiniBooNE, NuMI, off-axis PACS: 14.60.Pq,14.60.Lm,13.15.+g INTRODUCTION The NuMI beamline 1 produces neutrinos for the MINOS experiment...

111

The Power of Neutrino Mass Sum Rules for Neutrinoless Double Beta Decay Experiments  

E-Print Network (OSTI)

Neutrino mass sum rules relate the three neutrino masses within generic classes of flavour models, leading to restrictions on the effective mass parameter measured in experiments on neutrinoless double beta decay as a function of the lightest neutrino mass. We perform a comprehensive study of the implications of such neutrino mass sum rules, which provide a link between model building, phenomenology, and experiments. After a careful explanation of how to derive predictions from sum rules, we discuss a large number of examples both numerically, using all three global fits available for the neutrino oscillation data, and analytically wherever possible. In some cases, our results disagree with some of those in the literature for reasons that we explain. Finally we discuss the experimental prospects for many current and near-future experiments, with a particular focus on the uncertainties induced by the unknown nuclear physics involved. We find that, in many cases, the power of the neutrino mass sum rules is so strong as to allow certain classes of models to be tested by the next generation of neutrinoless double beta decay experiments. Our study can serve as both a guideline and a theoretical motivation for future experimental studies.

Stephen F. King; Alexander Merle; Alexander J. Stuart

2013-07-31T23:59:59.000Z

112

Solar models and solar neutrino oscillations John N Bahcall and Carlos Pea-Garay  

E-Print Network (OSTI)

Solar models and solar neutrino oscillations John N Bahcall and Carlos Peña-Garay Institute and experimental, of solar neutrino fluxes and of the masses and mixing angles that characterize solar neutrino oscillations. We also summarize the principal reasons for performing new solar neutrino experiments and what we

Bahcall, John

113

Solar models and solar neutrino oscillations John N Bahcall and Carlos PeaGaray  

E-Print Network (OSTI)

Solar models and solar neutrino oscillations John N Bahcall and Carlos Peña­Garay Institute and experimental, of solar neutrino fluxes and of the masses and mixing angles that characterize solar neutrino oscillations. We also summarize the principal reasons for performing new solar neutrino experiments and what we

Bahcall, John

114

Neutrino mass, lepton number, and the origin of matter  

E-Print Network (OSTI)

antiparticles? And many other things% Do neutrinos violate CP? #12;Neutrinoless Double Beta Decay W. Rodejohann? #12;Neutrinoless Double Beta Decay 1 sigma W. Rodejohann, 1206.2560 #12;14 F. Iachello #12;15 Regions

115

Dark Matter and Lepton Flavour Violation in a Hybrid Neutrino Mass Model  

E-Print Network (OSTI)

We describe a hybrid model in which the light neutrino mass matrix receives both tree-level seesaw and loop-induced contributions. An additional U(1) gauge symmetry is used to stabilize the lightest right-handed neutrino as the Dark Matter candidate. After fitting the experimental neutrino data, we analyze and correlate the phenomenological consequences of the model, namely its impact on electroweak precision measurements, the Dark Matter relic abundance, lepton flavour violating rare decays and neutrinoless double beta decay. We find that natural realizations of the model characterized by large Yukawa couplings are compatible with and close to the current experimental limits.

Deppisch, Frank F

2014-01-01T23:59:59.000Z

116

A new strategy for probing the Majorana neutrino CP violating phases and masses  

E-Print Network (OSTI)

We propose a new strategy for detecting the CP-violating phases and the effective mass of muon Majorana neutrinos by measuring observables associated with neutrino-antineutrino oscillations in $\\pi^{\\pm}$ decays. Within the generic framework of quantum field theory, we compute the non-factorizable probability for producing a pair of same-charged muons in $\\pi^{\\pm}$ decays as a distinctive signature of $\

Delepine, David; Castro, Gabriel Lopez

2009-01-01T23:59:59.000Z

117

Probing dark energy and neutrino mass from upcoming lensing experiments of CMB and galaxies  

SciTech Connect

We discuss the synergy of the cosmic shear and CMB lensing experiments to simultaneously constrain the neutrino mass and dark energy properties. Taking fully account of the CMB lensing, cosmic shear, CMB anisotropies, and their cross correlation signals, we clarify a role of each signal, and investigate the extent to which the upcoming observations by a high-angular resolution experiment of CMB and deep galaxy imaging survey can tightly constrain the neutrino mass and dark energy equation-of-state parameters. Including the primary CMB information as a prior cosmological information, the Fisher analysis reveals that the time varying equation-of-state parameters, given by w(a) = w{sub 0}+w{sub a}(1?a), can be tightly constrained with the accuracies of 5% for w{sub 0} and 15% for w{sub a}, which are comparable to or even better than those of the stage-III type surveys neglecting the effect of massive neutrinos. In other words, including the neutrino mass in the parameter estimation would not drastically alter the figure-of-Merit estimates of dark energy parameters from the weak lensing measurements. For the neutrino mass, a clear signal for total neutrino mass with ? 0.1 eV can be detected with ? 2-? significance. The robustness and sensitivity of these results are checked in detail by allowing the setup of cosmic shear experiment to vary as a function of observation time or exposure time, showing that the improvement of the constraints very weakly depends on the survey parameters, and the results mentioned above are nearly optimal for the dark energy parameters and the neutrino mass.

Namikawa, Toshiya; Saito, Shun [Department of Physics, Graduate School of Science, The University of Tokyo, Tokyo 113-0033 (Japan); Taruya, Atsushi, E-mail: namikawa@utap.phys.s.u-tokyo.ac.jp, E-mail: ssaito@astro.berkeley.edu, E-mail: ataruya@utap.phys.s.u-tokyo.ac.jp [Research Center for the Early Universe, School of Science, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033 (Japan)

2010-12-01T23:59:59.000Z

118

SLIM at LHC: LHC search power for a model linking dark matter and neutrino mass  

Science Journals Connector (OSTI)

Recently a model has been proposed that links dark matter and neutrino masses. The dark matter candidate which is dubbed as SLIM has a mass of MeV scale and can show up at low energy experiments. The model als...

Y. Farzan; M. Hashemi

2010-11-01T23:59:59.000Z

119

neutrino-properties-web.dvi  

NLE Websites -- All DOE Office Websites (Extended Search)

THE THE NEUTRINO PROPERTIES LISTINGS Revised August 2013 by P. Vogel (Caltech) and A. Piepke (University of Alabama). The following Listings concern measurements of various properties of neutrinos. Nearly all of the measurements, all of which so far are limits, actually concern superpositions of the mass eigenstates ν i , which are in turn related to the weak eigenstates ν ℓ , via the neutrino mixing matrix |ν ℓ = i U ℓi |ν i . In the analogous case of quark mixing via the CKM matrix, the smallness of the off-diagonal terms (small mixing angles) permits a "dominant eigenstate" approximation. However, the results of neutrino oscillation searches show that the mixing matrix contains two large mixing angles and a third angle that is not exceedingly small. We cannot, therefore, associate any particular state |ν i with any particular lepton label e, µ or τ . Nevertheless,

120

STATUS OF THE MILANO NEUTRINO MASS EXPERIMENT WITH THERMAL DETECTORS  

E-Print Network (OSTI)

Science, University of California, Berkeley CA 94720, USA In this paper we present our recent developments eV. The recent hints on atmospheric, solar and reactor neutrino oscillations 1 increase the interest=C and therefore any material with a low heat capacity C

Note: This page contains sample records for the topic "neutrino mass mixing" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Systematic errors in the measurement of neutrino masses due to baryonic feedback processes: Prospects for stage IV lensing surveys  

E-Print Network (OSTI)

We examine the importance of baryonic feedback effects on the matter power spectrum on small scales, and the implications for the precise measurement of neutrino masses through gravitational weak lensing. Planned large galaxy surveys such as the Large Synoptic Sky Telescope (LSST) and Euclid are expected to measure the sum of neutrino masses to extremely high precision, sufficient to detect non-zero neutrino masses even in the minimal mass normal hierarchy. We show that weak lensing of galaxies while being a very good probe of neutrino masses, is extremely sensitive to baryonic feedback processes. We use publicly available results from the Overwhelmingly Large Simulations (OWLS) project to investigate the effects of active galactic nuclei feedback, the nature of the stellar initial mass function, and gas cooling rates, on the measured weak lensing shear power spectrum. Using the Fisher matrix formalism and priors from CMB+BAO data, we show that when one does not account for feedback, the measured neutrino mas...

Natarajan, Aravind; Battaglia, Nicholas; Trac, Hy

2014-01-01T23:59:59.000Z

122

WiggleZ Dark Energy Survey: Cosmological neutrino mass constraint from blue high-redshift galaxies  

Science Journals Connector (OSTI)

The absolute neutrino mass scale is currently unknown, but can be constrained by cosmology. The WiggleZ high redshift, star-forming, and blue galaxy sample offers a complementary data set to previous surveys for performing these measurements, with potentially different systematics from nonlinear structure formation, redshift-space distortions, and galaxy bias. We obtain a limit of ?m?<0.60??eV (95% confidence) for WiggleZ+Wilkinson?Microwave?Anisotropy?Probe. Combining with priors on the Hubble parameter and the baryon acoustic oscillation scale gives ?m?<0.29??eV, which is the strongest neutrino mass constraint derived from spectroscopic galaxy redshift surveys.

Signe RiemerSrensen et al.

2012-04-23T23:59:59.000Z

123

E-Print Network 3.0 - active-unsterile neutrino mixing Sample...  

NLE Websites -- All DOE Office Websites (Extended Search)

University, Atomic Physics Collection: Fission and Nuclear Technologies ; Physics 7 Phenomenology of FourthPhenomenology of Fourth Generation NeutrinosGeneration Neutrinos Summary:...

124

ADDENDUM on the mass neutrino oscillation in a gravitational field  

E-Print Network (OSTI)

In the article {\\it Gen. Rel. Grav.} {\\bf 32}, 1633 (2000), by J. G. Pereira and C. M. Zhang, the special relativity energy-momentum tensor was used to discuss the neutrino phase-splitting in a weak gravitational field. However, it would be more appropriate to use the general relativity energy-momentum tensor. When we do that, as we are going to see, some results change, but the basic conclusion remains the same.

J. G. Pereira; C. M. Zhang

2002-05-08T23:59:59.000Z

125

GSI Oscillations as Interference of Neutrino Flavour Mass--Eigenstates and Measuring Process  

E-Print Network (OSTI)

This paper is addressed to the proof of the important role of measuring apparatus, i.e. the measuring process, in the formation of necessary and sufficient conditions for the explanation of a time modulation of K-shell electron capture (EC) decay rates of hydrogen-like (H-like) heavy ions (or the GSI oscillations) as the interference of neutrino mass-eigenstates of the electron neutrino constituents. For our analysis we use a toy-model, which has been recently proposed by Peshkin arXiv: 1403.4292 [nucl-th] for a verification of the mechanism of the GSI oscillations as the interference of neutrino mass-eigenstates by Ivanov and Kienle Phys. Rev. Lett. 103, 062502 (2009).

Ivanov, A N

2014-01-01T23:59:59.000Z

126

GSI Oscillations as Interference of Neutrino Flavour Mass--Eigenstates and Measuring Process  

E-Print Network (OSTI)

This paper is addressed to the proof of the important role of measuring apparatus, i.e. the measuring process, in the formation of necessary and sufficient conditions for the explanation of a time modulation of K-shell electron capture (EC) decay rates of hydrogen-like (H-like) heavy ions (or the GSI oscillations) as the interference of neutrino mass-eigenstates of the electron neutrino constituents. For our analysis we use a toy-model, which has been recently proposed by Peshkin arXiv: 1403.4292 [nucl-th] for a verification of the mechanism of the GSI oscillations as the interference of neutrino mass-eigenstates by Ivanov and Kienle Phys. Rev. Lett. 103, 062502 (2009).

A. N. Ivanov; P. Kienle

2014-06-10T23:59:59.000Z

127

Gravitational wave generated by mass ejection in protoneutron star neutrino burst  

SciTech Connect

In this work we discuss the mechanism of mass ejection in protoneutron stars induced by diffusion of neutrinos. A dynamical calculation is employed in order to determine the amount of matter ejected and the properties of the remnant compact object [1]. The equations of state of this supra-nuclear regime [2] is properly linked with others describing the different sub-nuclear regimes of density [3, 4, 5]. For specified initial configurations of the protoneutron star, we solve numerically the set of equations of motion together with a schematic treatment of the neutrino transport through the dense stellar medium. We investigate the gravitational waves production accompanying the mass ejection induced by the neutrino burst. It is estimated the gravitational wave intensity and the detection of such wave by the existing detector or near future project for this purpose is discussed.

Almeida, L. G. [Universidade Federal do Acre-Campus Floresta, Estrada do Canela Fina, km 12, 69980-000, Cruzeiro do Sul, AC (Brazil); Centro Brasileiro de Pesquisas Fisicas, Rua Dr. Xavier Sigaud 150, 22290-180, Rio de Janeiro, RJ (Brazil); Rodrigues, H.; Portes, D. JR. [Centro Federal de Educacao Tecnologica do Rio de Janeiro Av. Maracana 249, 20271-110, Rio de Janeiro, RJ (Brazil); Duarte, S. B. [Centro Brasileiro de Pesquisas Fisicas, Rua Dr. Xavier Sigaud 150, 22290-180, Rio de Janeiro, RJ (Brazil)

2010-11-12T23:59:59.000Z

128

Neutrino_Lectures_1and2  

NLE Websites -- All DOE Office Websites (Extended Search)

NuTeV sin 2 W Measurement Direct Neutrino Mass Measurements Neutrino Oscillation Phenomenology Solar Neutrinos (part 1) Lecture 2: Solar Neutrinos (part 2) Atmospheric and...

129

Top-Quark Mass Data and the Sum of Quasi-Degenerate Neutrino Masses (One small electroweak-bound e-parameter organizes elementary particle 3-flavor phenomenology)  

E-Print Network (OSTI)

The absolute neutrino masses and type of neutrino mass hierarchy are among the main problems in neutrino physics. Top-quark mass is another topical problem in particle physics. These problems extend the old puzzle of electron-muon mass ratio close to the fine structure constant, which is still not solved by known theory. Here I continue the search for a general flavor pattern that may incorporate these problems. Relations between neutrino/electron and electron/top-quark pole mass ratios are obtained from supposition that realistic elementary particle dimensionless bare flavor quantities are small deviated (measured by universal parameter e) from the values of a stated flavor pattern (at e=0) and experimental data hints. With the world average t-quark mass data the sum of QD-neutrino masses is estimated (0.50 +- 0.003)eV in agreement with cosmological constraints and known QD-neutrino mass estimations from experimental data on neutrino oscillation mass-squared differences.

E. M. Lipmanov

2008-10-01T23:59:59.000Z

130

MADPH071500 IZTECHP07/05 DESY07213 Dirac Neutrino Masses from Generalized Supersymmetry Breaking  

E-Print Network (OSTI)

#ective Dirac mass terms involving the ``wrong Higgs'' field can arise either at tree level due to hard. The neutrino magnetic and electric dipole moments resulting from the radiative mechanism also vanish at one the ultraviolet behavior of the SM beyond Fermi ener­ gies. Low­energy softly­broken supersymmetry thus pro­ vides

131

What neutrinoless double beta decay would tell us about neutrino mass  

Science Journals Connector (OSTI)

We identify several types of gauge theories which together comprise a very broad range in which the observation of neutrinoless double beta decay would imply a significant lower bound on neutrino mass. We explain why these gauge theories have this property.

Boris Kayser

1992-01-01T23:59:59.000Z

132

Determination of ?23 in long-baseline neutrino oscillation experiments with three-flavor mixing effects  

Science Journals Connector (OSTI)

We examine the accuracy of ?23 determination in future long-baseline (LBL) ?? disappearance experiments in the three-flavor mixing scheme of neutrinos. Despite that the error of sin?22?23 is indeed a few percent level at around the maximal mixing, we show that the error of physics variable s232 is large, ?(s232)/s232?10-20%, depending upon regions of ?23. The errors are severely affected by the octant degeneracy of ?23, and ?(s232) is largely amplified by the Jacobian factor relating these two variables in a region near the maximal mixing. The errors are also affected by the uncertainty due to the unknown value of ?13; ?(s232) is doubled at off maximal in the second octant of ?23 where the effect is largest. To overcome this problem, we discuss combined analysis with ?e appearance measurement in LBL experiments, or with reactor measurement of ?13. For possible relevance of subleading effects even in the next generation LBL experiments, we give a self-contained derivation of the survival probability to the next to leading order in s132 and ?m212/?m312.

Hisakazu Minakata; Masashi Sonoyama; Hiroaki Sugiyama

2004-12-23T23:59:59.000Z

133

On the minimum dark matter mass testable by neutrinos from the Sun  

SciTech Connect

We discuss a limitation on extracting bounds on the scattering cross section of dark matter with nucleons, using neutrinos from the Sun. If the dark matter particle is sufficiently light (less than about 4 GeV), the effect of evaporation is not negligible and the capture process goes in equilibrium with the evaporation. In this regime, the flux of solar neutrinos of dark matter origin becomes independent of the scattering cross section and therefore no constraint can be placed on it. We find the minimum values of dark matter masses for which the scattering cross section on nucleons can be probed using neutrinos from the Sun. We also provide simple and accurate fitting functions for all the relevant processes of GeV-scale dark matter in the Sun.

Busoni, Giorgio; Simone, Andrea De; Huang, Wei-Chih, E-mail: giorgio.busoni@sissa.it, E-mail: andrea.desimone@sissa.it, E-mail: wei-chih.huang@sissa.it [SISSA and INFN, Sezione di Trieste, via Bonomea 265, I-34136 Trieste (Italy)

2013-07-01T23:59:59.000Z

134

The WiggleZ Dark Energy Survey: Cosmological neutrino mass constraint from blue high-redshift galaxies  

E-Print Network (OSTI)

The absolute neutrino mass scale is currently unknown, but can be constrained from cosmology. The WiggleZ high redshift star-forming blue galaxy sample is less sensitive to systematics from non-linear structure formation, redshift-space distortions and galaxy bias than previous surveys. We obtain a upper limit on the sum of neutrino masses of 0.60eV (95% confidence) for WiggleZ+Wilkinson Microwave Anisotropy Probe. Combining with priors on the Hubble Parameter and the baryon acoustic oscillation scale gives an upper limit of 0.29eV, which is the strongest neutrino mass constraint derived from spectroscopic galaxy redshift surveys.

Signe Riemer-Srensen; Chris Blake; David Parkinson; Tamara M. Davis; Sarah Brough; Matthew Colless; Carlos Contreras; Warrick Couch; Scott Croom; Darren Croton; Michael J. Drinkwater; Karl Forster; David Gilbank; Mike Gladders; Karl Glazebrook; Ben Jelliffe; Russell J. Jurek; I-hui Li; Barry Madore; D. Christopher Martin; Kevin Pimbblet; Gregory B. Poole; Michael Pracy; Rob Sharp; Emily Wisnioski; David Woods; Ted K. Wyder; H. K. C. Yee

2011-12-21T23:59:59.000Z

135

Neutrino mass and dark matter in light of recent AMS-02 results  

Science Journals Connector (OSTI)

We study a simple extension of the Standard Model supplemented by an electroweak triplet scalar field to accommodate small neutrino masses by the type-II seesaw mechanism, while an additional singlet scalar field can play the role of cold dark matter (DM) in our Universe. This DM candidate is leptophilic for a wide range of model parameter space, and the lepton flux due to its annihilation carries information about the neutrino mass hierarchy. Using the recently released high-precision data on positron fraction and flux from the AMS-02 experiment, we examine the DM interpretation of the observed positron excess in our model for two kinematically distinct scenarios with the DM and triplet scalar masses (a) nondegenerate (mDM?m?) and (b) quasidegenerate (mDM?m?). We find that a good fit to the AMS-02 data can be obtained in both cases (a) and (b) with a normal hierarchy of neutrino masses, while the inverted hierarchy case is somewhat disfavored. Although we require a larger boost factor for the normal hierarchy case, this is still consistent with the current upper limits derived from Fermi-LAT and IceCube data for case (a). Moreover, the absence of an excess antiproton flux as suggested by PAMELA data sets an indirect upper limit on the DM-nucleon spin-independent elastic scattering cross section, which is stronger than the existing DM direct detection bound from LUX in the AMS-02 preferred DM mass range.

P.?S. Bhupal Dev; Dilip Kumar Ghosh; Nobuchika Okada; Ipsita Saha

2014-05-02T23:59:59.000Z

136

Neutrino Physics AAPT Strand Day  

NLE Websites -- All DOE Office Websites (Extended Search)

Physics AAPT Strand Day NSTA Regional, 2005 Jocelyn Monroe, Columbia University 1. What Is a Neutrino Anyway? 2. The Question Of Neutrino Mass 3. Searching For Neutrino...

137

Optimizing the Determination of the Neutrino Mixing Angle $?_{13}$ from Reactor Data  

E-Print Network (OSTI)

The technical breakthroughs of multiple detectors developed by Daya Bay and RENO collaborations have gotten great attention. Yet the optimal determination of neutrino mixing parameters from reactor data depends on the statistical method and demands equal attention. We find that a straightforward method using a minimal parameters will generally outperform a multi-parameter method by delivering more reliable values with sharper resolution. We review standard confidence levels and statistical penalties for models using extra parameters, and apply those rules to our analysis. We find that the methods used in recent work of the Daya Bay and RENO collaborations have several undesirable properties. The existing work also uses non-standard measures of significance which we are unable to explain. A central element of the current methods consists of variationally fitting many more parameters than data points. As a result the experimental resolution of $\\sin ^{2}(2\\theta _{13})$ is degraded. The results also become extremely sensitive to certain model parameters that can be adjusted arbitrarily. The number of parameters to include in evaluating significance is an important issue that has generally been overlooked. The measures of significance applied previously would be consistent if and only if all parameters but one were considered to have no physical relevance for the experiment's hypothesis test. Simpler, more transparent methods can improve the determination of the mixing angle $\\theta _{13}$ from reactor data, and exploit the advantages from superb hardware technique of the experiments. We anticipate that future experimental analysis will fully exploit those advantages.

Amir N. Khan; Douglas W. McKay; John P. Ralston

2014-01-17T23:59:59.000Z

138

Systematic errors in the measurement of neutrino masses due to baryonic feedback processes: Prospects for stage IV lensing surveys  

E-Print Network (OSTI)

We examine the importance of baryonic feedback effects on the matter power spectrum on small scales, and the implications for the precise measurement of neutrino masses through gravitational weak lensing. Planned large galaxy surveys such as the Large Synoptic Sky Telescope (LSST) and Euclid are expected to measure the sum of neutrino masses to extremely high precision, sufficient to detect non-zero neutrino masses even in the minimal mass normal hierarchy. We show that weak lensing of galaxies while being a very good probe of neutrino masses, is extremely sensitive to baryonic feedback processes. We use publicly available results from the Overwhelmingly Large Simulations (OWLS) project to investigate the effects of active galactic nuclei feedback, the nature of the stellar initial mass function, and gas cooling rates, on the measured weak lensing shear power spectrum. Using the Fisher matrix formalism and priors from CMB+BAO data, we show that when one does not account for feedback, the measured neutrino mass may be substantially larger or smaller than the true mass, depending on the dominant feedback mechanism, with the mass error |\\Delta m_nu| often exceeding the mass m_nu itself. We also consider gravitational lensing of the cosmic microwave background (CMB) and show that it is not sensitive to baryonic feedback on scales l power spectrum can be measured to similar accuracy.

Aravind Natarajan; Andrew R. Zentner; Nicholas Battaglia; Hy Trac

2014-09-04T23:59:59.000Z

139

Nucleon effective masses within the Brueckner-Hartree-Fock theory: Impact on stellar neutrino emission  

E-Print Network (OSTI)

We calculate the effective masses of neutrons and protons in dense nuclear matter within the microscopic Brueckner-Hartree-Fock many-body theory and study the impact on the neutrino emissivity processes of neutron stars. We compare results based on different nucleon-nucleon potentials and nuclear three-body forces. Useful parametrizations of the numerical results are given. We find substantial in-medium suppression of the emissivities, strongly dependent on the interactions.

Baldo, M; Schulze, H -J; Taranto, G

2014-01-01T23:59:59.000Z

140

No Collective Neutrino Flavor Conversions during the Supernova Accretion Phase  

SciTech Connect

We perform a dedicated study of the supernova (SN) neutrino flavor evolution during the accretion phase, using results from recent neutrino radiation hydrodynamics simulations. In contrast to what was expected in the presence of only neutrino-neutrino interactions, we find that the multiangle effects associated with the dense ordinary matter suppress collective oscillations. The matter suppression implies that neutrino oscillations will start outside the neutrino decoupling region and therefore will have a negligible impact on the neutrino heating and the explosion dynamics. Furthermore, the possible detection of the next galactic SN neutrino signal from the accretion phase, based on the usual Mikheyev-Smirnov-Wolfenstein effect in the SN mantle and Earth matter effects, can reveal the neutrino mass hierarchy in the case that the mixing angle {theta}{sub 13} is not very small.

Chakraborty, Sovan; Mirizzi, Alessandro; Saviano, Ninetta; Tomas, Ricard [II Institut fuer Theoretische Physik, Universitaet Hamburg, Luruper Chaussee 149, 22761 Hamburg (Germany); Fischer, Tobias [GSI, Helmholtzzentrum fuer Schwerionenforschung GmbH, Planckstrasse 1, 64291 Darmstadt (Germany); Technische Universitaet Darmstadt, Schlossgartenstrasse 9, 64289 Darmstadt (Germany)

2011-10-07T23:59:59.000Z

Note: This page contains sample records for the topic "neutrino mass mixing" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Testing the Reactor and Gallium Anomalies with Intense (Anti)Neutrino Emitters  

E-Print Network (OSTI)

Several observed anomalies in neutrino oscillation data could be explained by a hypothetical fourth neutrino separated from the three standard neutrinos by a squared mass difference of a few 0.1 eV$^2$ or more. This hypothesis can be tested with MCi neutrino electron capture sources ($^{51}$Cr) or kCi antineutrino $\\beta$-source ($^{144}$Ce) deployed inside or next to a large low background neutrino detector. In particular, the compact size of this source coupled with the localization of the interaction vertex lead to an oscillating pattern in event spatial (and possibly energy) distributions that would unambiguously determine neutrino mass differences and mixing angles.

Th. Lasserre

2012-09-23T23:59:59.000Z

142

New mechanism for neutrino mass generation and triply charged Higgs bosons at the LHC  

SciTech Connect

We propose a new mechanism for generating small neutrino masses which predicts the relation m{sub {nu}}{approx}v{sup 4}/M{sup 3}, where v is the electroweak scale, rather than the conventional seesaw formula m{sub {nu}}{approx}v{sup 2}/M. Such a mass relation is obtained via effective dimension seven operators LLHH(H{sup {dagger}}H)/M{sup 3}, which arise when an isospin 3/2 Higgs multiplet {phi} is introduced along with isotriplet leptons. The masses of these particles are naturally in the TeV scale. The triply charged Higgs boson contained in {phi} can be pair produced at the LHC and the Tevatron, with {phi}{sup +++} decaying into W{sup +}l{sup +}l{sup +} or W{sup +}W{sup +}W{sup +}, possibly with displaced vertices. The leptonic decays of {phi}{sup +++} will help discriminate between normal and inverted hierarchies of neutrino masses. This scenario also allows for raising the standard Higgs boson mass to values in excess of 500 GeV.

Babu, K. S.; Nandi, S.; Tavartkiladze, Zurab [Department of Physics and Oklahoma Center for High Energy Physics, Oklahoma State University, Stillwater, Oklahoma 74078 (United States)

2009-10-01T23:59:59.000Z

143

Short Baseline Neutrino  

NLE Websites -- All DOE Office Websites (Extended Search)

March 10, 2003 March 10, 2003 Jonathan Link, Columbia La Thuile A Little Neutrino Phenomenology If neutrinos have mass then they may oscillate between flavors. ) 27 . 1 ( sin...

144

ILC phenomenology in a TeV scale radiative seesaw model for neutrino mass, dark matter and baryon asymmetry  

E-Print Network (OSTI)

We discuss phenomenology in a new TeV scale model which would explain neutrino oscillation, dark matter, and baryon asymmetry of the Universe simultaneously by the dynamics of the extended Higgs sector and TeV-scale right-handed neutrinos. Tiny neutrino masses are generated at the three-loop level due to the exact $Z_2$ symmetry, by which the stability of the dark matter candidate is guaranteed. The model provides various discriminative predictions in Higgs phenomenology, which can be tested at the Large Hadron Collider and the International Linear Collider.

Mayumi Aoki; Shinya Kanemura; Osamu Seto

2010-08-14T23:59:59.000Z

145

E-Print Network 3.0 - active neutrino masses Sample Search Results  

NLE Websites -- All DOE Office Websites (Extended Search)

Nazionale di Fisica Nucleare, Milano Weak Interactions Group Collection: Physics 6 Phenomenology of FourthPhenomenology of Fourth Generation NeutrinosGeneration Neutrinos Summary:...

146

Non-stationary hyperaccretion of stellar-mass black holes in three dimensions: Torus evolution and neutrino emission  

E-Print Network (OSTI)

We present three-dimensional hydrodynamic simulations of the evolution of selfgravitating, thick accretion discs around hyperaccreting stellar-mass black holes. The black hole-torus systems are considered to be remnants of compact object mergers, in which case the disc is not fed by an external mass reservoir and the accretion is non-stationary. Our models take into account viscous dissipation, described by an alpha-law, a detailed equation of state for the disc gas, and an approximate treatment of general relativistic effects on the disc structure by using a pseudo-Newtonian potential for the black hole including its possible rotation and spin-up during accretion. Magnetic fields are ignored. The neutrino emission of the hot disc is treated by a neutrino-trapping scheme, and the neutrino-antineutrino annihilation near the disc is evaluated in a post-processing step. Our simulations show that the neutrino emission and energy deposition by neutrino-antineutrino annihilation increase sensitively with the disc mass, with the black hole spin in case of a disc in corotation, and in particular with the alpha-viscosity. We find that for sufficiently large alpha-viscosity neutrino-antineutrino annihilation can be a viable energy source for gamma-ray bursts.

S. Setiawan; M. Ruffert; H. -Th. Janka

2004-02-20T23:59:59.000Z

147

Radiative decay of keV-mass sterile neutrinos in a strongly magnetized plasma  

E-Print Network (OSTI)

The radiative decay of sterile neutrinos with typical masses of 10 keV is investigated in the presence of a strong magnetic field and degenerate plasma. Full account is taken of the strongly modified photon dispersion relation relative to vacuum. The limiting cases of relativistic and non-relativistic plasma are analyzed. The decay rate in a strongly magnetized plasma as a function of the electron number density is compared with the un-magnetized case. We find that a strong magnetic field suppresses the catalyzing influence of the plasma on the decay rate.

Dobrynina, Alexandra A; Raffelt, Georg G

2014-01-01T23:59:59.000Z

148

Radiative decay of keV-mass sterile neutrinos in a strongly magnetized plasma  

E-Print Network (OSTI)

The radiative decay of sterile neutrinos with typical masses of 10 keV is investigated in the presence of a strong magnetic field and degenerate plasma. Full account is taken of the strongly modified photon dispersion relation relative to vacuum. The limiting cases of relativistic and non-relativistic plasma are analyzed. The decay rate in a strongly magnetized plasma as a function of the electron number density is compared with the un-magnetized case. We find that a strong magnetic field suppresses the catalyzing influence of the plasma on the decay rate.

Alexandra A. Dobrynina; Nicolay V. Mikheev; Georg G. Raffelt

2014-10-29T23:59:59.000Z

149

$N_{\\rm eff}$ in low-scale seesaw models versus the lightest neutrino mass  

E-Print Network (OSTI)

We evaluate the contribution to $N_{\\rm eff}$ of the extra sterile states in low-scale Type I seesaw models (with three extra sterile states). We explore the full parameter space and find that at least two of the heavy states always reach thermalisation in the Early Universe, while the third one might not thermalise provided the lightest neutrino mass is below ${\\mathcal O}(10^{-3}$eV). Constraints from cosmology therefore severely restrict the spectra of heavy states in the range 1eV- 100 MeV. The implications for neutrinoless double beta decay are also discussed.

Hernandez, P; Lopez-Pavon, J

2014-01-01T23:59:59.000Z

150

Lepton Mixing and Cancellation of the Dirac Mass Hierarchy in SO(10) GUTs with Flavor Symmetries T7 and Sigma(81)  

E-Print Network (OSTI)

In SO(10) grand unified theories (GUTs) the hierarchy which is present in the Dirac mass term of the neutrinos is generically as strong as the one in the up-type quark mass term. We propose a mechanism to partially or completely cancel this hierarchy in the light neutrino mass matrix in the seesaw context. The two main ingredients of the cancellation mechanism are the existence of three fermionic gauge singlets and of a discrete flavor symmetry G_f which is broken at a higher scale than SO(10). Two realizations of the cancellation mechanism are presented. The realization based on the Frobenius group T7 = Z7 x Z3 leads to a partial cancellation of the hierarchy and relates maximal 2-3 lepton mixing with the geometric hierarchy of the up-quark masses. In the realization with the group Sigma(81) the cancellation is complete and tri-bimaximal lepton mixing is reproduced at the lowest order. In both cases, to fully accommodate the leptonic data we take into account additional effects such as effects of higher-dimensional operators involving more than one flavon. The heavy neutral fermion mass spectra are considered. For both realizations we analyze the flavon potential at the renormalizable level as well as ways to generate the Cabibbo angle.

Claudia Hagedorn; Michael A. Schmidt; Alexei Yu. Smirnov

2008-11-18T23:59:59.000Z

151

Proton hexality from an anomalous flavor U(1) and neutrino masses--Linking to the string scale  

SciTech Connect

We devise minimalistic gauged U(1)_X Froggatt-Nielsen models which at low-energy give rise to the recently suggested discrete gauge Z_6 symmetry, proton hexality, thus stabilizing the proton. Assuming three generations of right-handed neutrinos, with the proper choice of X-charges, we obtain viable neutrino masses. Furthermore, we find scenarios such that no X-charged hidden sector superfields are needed, which from a bottom-up perspective allows the calculation of g_string, g_X and G_SM's Kac-Moody levels. The only mass scale apart from M_grav is m_soft.

Murayama, Hitoshi; Dreiner, Herbi K.; Luhn, Christoph; Murayama, Hitoshi; Thormeiere, Marc

2007-08-07T23:59:59.000Z

152

Solar Neutrinos and the Decaying Neutrino Hypothesis  

E-Print Network (OSTI)

We explore, mostly using data from solar neutrino experiments, the hypothesis that the neutrino mass eigenstates are unstable. We find that, by combining $^8$B solar neutrino data with those on $^7$Be and lower-energy solar neutrinos, one obtains a mostly model-independent bound on both the $\

Jeffrey M. Berryman; Andre de Gouvea; Daniel Hernandez

2014-11-02T23:59:59.000Z

153

Solar Neutrinos and the Decaying Neutrino Hypothesis  

E-Print Network (OSTI)

We explore, mostly using data from solar neutrino experiments, the hypothesis that the neutrino mass eigenstates are unstable. We find that, by combining $^8$B solar neutrino data with those on $^7$Be and lower-energy solar neutrinos, one obtains a mostly model-independent bound on both the $\

Berryman, Jeffrey M; Hernandez, Daniel

2014-01-01T23:59:59.000Z

154

Neutrinos: Theory and Phenomenology  

SciTech Connect

The theory and phenomenology of neutrinos will be addressed, especially that relating to the observation of neutrino flavor transformations. The current status and implications for future experiments will be discussed with special emphasis on the experiments that will determine the neutrino mass ordering, the dominant flavor content of the neutrino mass eigenstate with the smallest electron neutrino content and the size of CP violation in the neutrino sector. Beyond the neutrino Standard Model, the evidence for and a possible definitive experiment to confirm or refute the existence of light sterile neutrinos will be briefly discussed.

Parke, Stephen

2013-10-22T23:59:59.000Z

155

A measurement of neutrino oscillations with muon neutrinos in the MINOS experiment  

SciTech Connect

Experimental evidence has established that neutrino flavor states evolve over time. A neutrino of a particular flavor that travels some distance can be detected in a different neutrino flavor state. The Main Injector Neutrino Oscillation Search (MINOS) is a long-baseline experiment that is designed to study this phenomenon, called neutrino oscillations. MINOS is based at Fermilab near Chicago, IL, and consists of two detectors: the Near Detector located at Fermilab, and the Far Detector, which is located in an old iron mine in Soudan, MN. Both detectors are exposed to a beam of muon neutrinos from the NuMI beamline, and MINOS measures the fraction of muon neutrinos that disappear after traveling the 734 km between the two detectors. One can measure the atmospheric neutrino mass splitting and mixing angle by observing the energy-dependence of this muon neutrino disappearance. MINOS has made several prior measurements of these parameters. Here I describe recently-developed techniques used to enhance our sensitivity to the oscillation parameters, and I present the results obtained when they are applied to a dataset that is twice as large as has been previously analyzed. We measure the mass splitting {Delta}m{sub 23}{sup 2} = (2.32{sub -0.08}{sup +0.12}) x 10{sup -3} eV{sup 2}/c{sup 4} and the mixing angle sin{sup 2}(2{theta}{sub 32}) > 0.90 at 90% C.L. These results comprise the world's best measurement of the atmospheric neutrino mass splitting. Alternative disappearance models are also tested. The neutrino decay hypothesis is disfavored at 7.2{sigma} and the neutrino quantum decoherence hypothesis is disfavored at 9.0{sigma}.

Coleman, Stephen James; /William-Mary Coll.

2011-01-01T23:59:59.000Z

156

Determining the neutrino mass hierarchy and CP violation in NoVA with a second off-axis detector  

SciTech Connect

We consider a Super-NOVA-like experimental configuration based on the use of two detectors in a long-baseline experiment as NOVA. We take the far detector as in the present NOVA proposal and add a second detector at a shorter baseline. The location of the second off-axis detector is chosen such that the ratio L/E is the same for both detectors, being L the baseline and E the neutrino energy. We consider liquid argon and water- Cerenkov techniques for the second off-axis detector and study, for different experimental setups, the detector mass required for the determination of the neutrino mass hierarchy, for different values of {theta}{sub 13}. We also study the capabilities of such an experimental setup for determining CP-violation in the neutrino sector. Our results show that by adding a second off-axis detector a remarkable enhancement on the capabilities of the current NOVA experiment could be achieved.

Mena, Olga; /Fermilab; Palomares-Ruiz, Sergio; /Vanderbilt U.; Pascoli, Silvia; /CERN /Durham U., IPPP

2005-10-01T23:59:59.000Z

157

A new upper limit on the total neutrino mass from the 2dF Galaxy Redshift Survey  

E-Print Network (OSTI)

We constrain f_nu = Omega_nu / Omega_m, the fractional contribution of neutrinos to the total mass density in the Universe, by comparing the power spectrum of fluctuations derived from the 2dF Galaxy Redshift Survey with power spectra for models with four components: baryons, cold dark matter, massive neutrinos and a cosmological constant. Adding constraints from independent cosmological probes we find f_nu < 0.13 (at 95% confidence) for a prior of 0.1< Omega_m <0.5, and assuming the scalar spectral index n=1. This translates to an upper limit on the total neutrino mass and m_nu,tot < 1.8 eV for "concordance" values of Omega_m and the Hubble constant. Very similar results are obtained with a prior on Omega_m from Type Ia supernovae surveys, and with marginalization over n.

O. Elgaroy; O. Lahav; W. J. Percival; J. A. Peacock; D. S. Madgwick; S. L. Bridle; C. M. Baugh; I. K. Baldry; J. Bland-Hawthorn; T. Bridges; R. Cannon; S. Cole; M. Colless; C. Collins; W. Couch; G. Dalton; R. De Propris; S. P. Driver; G. P. Efstathiou; R. S. Ellis; C. S. Frenk; K. Glazebrook; C. Jackson; I. Lewis; S. Lumsden; S. Maddox; P. Norberg; B. A. Peterson; W. Sutherland; K. Taylor

2002-06-14T23:59:59.000Z

158

Searches for sterile neutrinos with IceCube DeepCore  

Science Journals Connector (OSTI)

We show that study of the atmospheric neutrinos in the 10100GeV energy range by DeepCore subarray of the IceCube Neutrino Observatory can substantially constrain the mixing of sterile neutrinos of mass ?1??eV with active neutrinos. In the scheme with one sterile neutrino we calculate ?? and ?? oscillation probabilities as well as zenith angle distributions of ??CC (charge current) events in different energy intervals in DeepCore. The distributions depend on the mass hierarchy of active neutrinos. Therefore, in principle, the hierarchy can be identified, if ?s exists. After a few years of exposure the DeepCore data will allow us to exclude the mixing of |U?4|2?0.02 indicated by the LSND/MiniBooNE results. Combination of the DeepCore and high-energy IceCube data will further improve sensitivity to ?s mixing parameters.

Soebur Razzaque and A. Yu. Smirnov

2012-05-18T23:59:59.000Z

159

Neutrinos in Nuclear Physics  

E-Print Network (OSTI)

Since the discovery of nuclear beta decay, nuclear physicists have studied the weak interaction and the nature of neutrinos. Many recent and current experiments have been focused on the elucidation of neutrino oscillations and neutrino mass. The quest for the absolute value of neutrino mass continues with higher precision studies of the tritium beta decay spectrum near the endpoint. Neutrino oscillations are studied through measurements of reactor neutrinos as a function of baseline and energy. And experiments searching for neutrinoless double beta decay seek to discover violation of lepton number and establish the Majorana nature of neutrino masses.

McKeown, R D

2014-01-01T23:59:59.000Z

160

Energy Loss of Neutrinos in 20M{center_dot} Star  

SciTech Connect

Current ideas on neutrino oscillation plus confirmation from neutrino experiments make possible the changing of neutrino flavor due to interactions with the electrons in medium. When neutrinos pass through a medium and interact with the electrons, an effective potential energy is produced due to coherent forward scattering that occurred in the medium. This potential engenders significant changes in the neutrino masses and their mixing in the medium. Thus electron neutrinos would oscillate into different mass eigenstate and this is dependent on the energy of the neutrinos. Some of the energy will be lost in the coherent scattering with the electrons by the charged current interaction. We have calculated the energy loss of the neutrinos by using a stopping power equation for a 20M{center_dot} star.

Ahmad, Nor Sofiah; Yusof, Norhasliza; Kassim, Hasan Abu [Department of Physics, University of Malaya, 50603, Kuala Lumpur (Malaysia)

2010-08-12T23:59:59.000Z

Note: This page contains sample records for the topic "neutrino mass mixing" from the National Library of EnergyBeta (NLEBeta).
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161

Searches for new physics at MiniBooNE : sterile neutrinos and mixing freedom  

E-Print Network (OSTI)

The MiniBooNE experiment was designed to perform a search for Vu --> Ve oscillations in a region of A[delta]sin 2 20very different from that allowed by standard, three neutrino oscillations, as determined by solar and ...

Karagiorgi, Georgia S. (Georgia Stelios)

2010-01-01T23:59:59.000Z

162

FEASIBILITY STUDY II OF A MUON BASED NEUTRINO SOURCE.  

SciTech Connect

The concept of using a muon storage ring to provide a well characterized beam of muon and electron neutrinos (a Neutrino Factory) has been under study for a number of years now at various laboratories throughout the world. The physics program of a Neutrino Factoryis focused on the relatively unexplored neutrino sector. In conjunction with a detector located a suitable distance from the neutrino source, the facility would make valuable contributions to the study of neutrino masses and lepton mixing. A Neutrino Factory is expected to improve the measurement accuracy of sin{sup 2}(2{theta}{sub 23}) and {Delta}m{sup 2}{sub 32} and provide measurements of sin{sup 2}(2{theta}{sub 13}) and the sign of {Delta}m{sup 2}{sub 32}. It may also be able to measure CP violation in the lepton sector.

GALLARDO,J.C.; OZAKI,S.; PALMER,R.B.; ZISMAN,M.

2001-06-30T23:59:59.000Z

163

Black Hole Formation in Core-Collapse Supernovae and Time-of-Flight Measurements of the Neutrino Masses  

E-Print Network (OSTI)

Early black hole formation in core-collapse supernovae may be triggered by mass accretion or a change in the high-density equation of state. We consider the possibility that black hole formation happens when the flux of neutrinos is still measurably high. If this occurs, then the neutrino signal from the supernova will be terminated abruptly (the transition takes $\\lesssim 0.5$ ms). The properties and duration of the signal before the cutoff are important measures of both the physics and astrophysics of the cooling proto-neutron star. For the event rates expected in present and proposed detectors, the cutoff will generally appear sharp, thus allowing model-independent time-of-flight mass tests for the neutrinos after the cutoff. If black hole formation occurs relatively early, within a few ($\\sim 1$) seconds after core collapse, then the expected luminosities are of order $L_{BH} = 10^{52}$ erg/s per flavor. In this case, the neutrino mass sensitivity can be extraordinary. For a supernova at a distance $D = 10$ kpc, SuperKamiokande can detect a $\\bar{\

J. F. Beacom; R. N. Boyd; A. Mezzacappa

2000-10-19T23:59:59.000Z

164

Neutrino mass mechanisms in 3-3-1 models: A short review  

E-Print Network (OSTI)

In this paper we review some mechanisms that provide light neutrinos in the framework of 3-3-1 gauge models without exotic leptons. In regard to the minimal 3-3-1 model, we call the attention to the fact that the perturbative regime of the model goes until 5 TeV. This requires alternative mechanisms in order to generate light neutrinos. In this review we discuss two mechanisms capable of generating light neutrinos in the framework of the minimal 3-3-1 model. In regard to the 3-3-1 model with right-handed neutrinos, we call the attention to the fact that in it mechanisms that generate light left-handed neutrinos also generate light right-handed neutrinos. Finally, we call the attention to the fact that the 3-3-1 model with right-handed neutrinos accommodate naturally the inverse seesaw mechanism.

Pires, C A de S

2014-01-01T23:59:59.000Z

165

HOLMES - The Electron Capture Decay of 163Ho to Measure the Electron Neutrino Mass with sub-eV sensitivity  

E-Print Network (OSTI)

The European Research Council has recently funded HOLMES, a new experiment to directly measure the neutrino mass. HOLMES will perform a calorimetric measurement of the energy released in the decay of 163Ho. The calorimetric measurement eliminates systematic uncertainties arising from the use of external beta sources, as in experiments with beta spectrometers. This measurement was proposed in 1982 by A. De Rujula and M. Lusignoli, but only recently the detector technological progress allowed to design a sensitive experiment. HOLMES will deploy a large array of low temperature microcalorimeters with implanted 163Ho nuclei. The resulting mass sensitivity will be as low as 0.4 eV. HOLMES will be an important step forward in the direct neutrino mass measurement with a calorimetric approach as an alternative to spectrometry. It will also establish the potential of this approach to extend the sensitivity down to 0.1 eV. We outline here the project with its technical challenges and perspectives.

B. Alpert; M. Balata; D. Bennett; M. Biasotti; C. Boragno; C. Brofferio; V. Ceriale; D. Corsini; M. De Gerone; R. Dressler; M. Faverzani; E. Ferri; J. Fowler; F. Gatti; A. Giachero; J. Hays-Wehle; S. Heinitz; G. Hilton; U. Koester; M. Lusignoli; M. Maino; J. Mates; S. Nisi; R. Nizzolo; A. Nucciotti; G. Pessina; G. Pizzigoni; A. Puiu; S. Ragazzi; C. Reintsema; M. Ribeiro Gomes; D. Schmidt; D. Schumann; M. Sisti; D. Swetz; F. Terranova; J. Ullom

2014-12-16T23:59:59.000Z

166

HOLMES - The Electron Capture Decay of 163Ho to Measure the Electron Neutrino Mass with sub-eV sensitivity  

E-Print Network (OSTI)

The European Research Council has recently funded HOLMES, a new experiment to directly measure the neutrino mass. HOLMES will perform a calorimetric measurement of the energy released in the decay of 163Ho. The calorimetric measurement eliminates systematic uncertainties arising from the use of external beta sources, as in experiments with beta spectrometers. This measurement was proposed in 1982 by A. De Rujula and M. Lusignoli, but only recently the detector technological progress allowed to design a sensitive experiment. HOLMES will deploy a large array of low temperature microcalorimeters with implanted 163Ho nuclei. The resulting mass sensitivity will be as low as 0.4 eV. HOLMES will be an important step forward in the direct neutrino mass measurement with a calorimetric approach as an alternative to spectrometry. It will also establish the potential of this approach to extend the sensitivity down to 0.1 eV. We outline here the project with its technical challenges and perspectives.

Alpert, B; Bennett, D; Biasotti, M; Boragno, C; Brofferio, C; Ceriale, V; Corsini, D; De Gerone, M; Dressler, R; Faverzani, M; Ferri, E; Fowler, J; Gatti, F; Giachero, A; Hays-Wehle, J; Heinitz, S; Hilton, G; Koester, U; Lusignoli, M; Maino, M; Mates, J; Nisi, S; Nizzolo, R; Nucciotti, A; Pessina, G; Pizzigoni, G; Puiu, A; Ragazzi, S; Reintsema, C; Gomes, M Ribeiro; Schmidt, D; Schumann, D; Sisti, M; Swetz, D; Terranova, F; Ullom, J

2014-01-01T23:59:59.000Z

167

BooNE: Booster Neutrino Experiment  

NLE Websites -- All DOE Office Websites (Extended Search)

BooNE will investigate the question of neutrino mass by searching for oscillations of muon neutrinos into electron neutrinos. This will be done by directing a muon neutrino beam...

168

CUORE and beyond: bolometric techniques to explore inverted neutrino mass hierarchy  

E-Print Network (OSTI)

The CUORE (Cryogenic Underground Observatory for Rare Events) experiment will search for neutrinoless double beta decay of $^{130}$Te. With 741 kg of TeO$_2$ crystals and an excellent energy resolution of 5 keV (0.2%) at the region of interest, CUORE will be one of the most competitive neutrinoless double beta decay experiments on the horizon. With five years of live time, CUORE projected neutrinoless double beta decay half-life sensitivity is $1.6\\times 10^{26}$ y at $1\\sigma$ ($9.5\\times10^{25}$ y at the 90% confidence level), which corresponds to an upper limit on the effective Majorana mass in the range 40--100 meV (50--130 meV). Further background rejection with auxiliary light detector can significantly improve the search sensitivity and competitiveness of bolometric detectors to fully explore the inverted neutrino mass hierarchy with $^{130}$Te and possibly other double beta decay candidate nuclei.

D. R. Artusa; F. T. Avignone III; O. Azzolini; M. Balata; T. I. Banks; G. Bari; J. Beeman; F. Bellini; A. Bersani; M. Biassoni; C. Brofferio; C. Bucci; X. Z. Cai; A. Camacho; L. Canonica; X. G. Cao; S. Capelli; L. Carbone; L. Cardani; M. Carrettoni; N. Casali; D. Chiesa; N. Chott; M. Clemenza; S. Copello; C. Cosmelli; O. Cremonesi; R. J. Creswick; I. Dafinei; A. Dally; V. Datskov; A. De Biasi; M. M. Deninno; S. Di Domizio; M. L. di Vacri; L. Ejzak; D. Q. Fang; H. A. Farach; M. Faverzani; G. Fernandes; E. Ferri; F. Ferroni; E. Fiorini; M. A. Franceschi; S. J. Freedman; B. K. Fujikawa; A. Giachero; L. Gironi; A. Giuliani; J. Goett; P. Gorla; C. Gotti; T. D. Gutierrez; E. E. Haller; K. Han; K. M. Heeger; R. Hennings-Yeomans; H. Z. Huang; R. Kadel; K. Kazkaz; G. Keppel; Yu. G. Kolomensky; Y. L. Li; C. Ligi; X. Liu; Y. G. Ma; C. Maiano; M. Maino; M. Martinez; R. H. Maruyama; Y. Mei; N. Moggi; S. Morganti; T. Napolitano; S. Nisi; C. Nones; E. B. Norman; A. Nucciotti; T. O'Donnell; F. Orio; D. Orlandi; J. L. Ouellet; M. Pallavicini; V. Palmieri; L. Pattavina; M. Pavan; M. Pedretti; G. Pessina; V. Pettinacci; G. Piperno; C. Pira; S. Pirro; E. Previtali; V. Rampazzo; C. Rosenfeld; C. Rusconi; E. Sala; S. Sangiorgio; N. D. Scielzo; M. Sisti; A. R. Smith; L. Taffarello; M. Tenconi; F. Terranova; W. D. Tian; C. Tomei; S. Trentalange; G. Ventura; M. Vignati; B. S. Wang; H. W. Wang; L. Wielgus; J. Wilson; L. A. Winslow; T. Wise; A. Woodcraft; L. Zanotti; C. Zarra; B. X. Zhu; S. Zucchelli

2014-07-04T23:59:59.000Z

169

CUORE and beyond: bolometric techniques to explore inverted neutrino mass hierarchy  

E-Print Network (OSTI)

The CUORE (Cryogenic Underground Observatory for Rare Events) experiment will search for neutrinoless double beta decay of $^{130}$Te. With 741 kg of TeO$_2$ crystals and an excellent energy resolution of 5 keV (0.2%) at the region of interest, CUORE will be one of the most competitive neutrinoless double beta decay experiments on the horizon. With five years of live time, CUORE projected neutrinoless double beta decay half-life sensitivity is $1.6\\times 10^{26}$ y at $1\\sigma$ ($9.5\\times10^{25}$ y at the 90% confidence level), which corresponds to an upper limit on the effective Majorana mass in the range 40--100 meV (50--130 meV). Further background rejection with auxiliary light detector can significantly improve the search sensitivity and competitiveness of bolometric detectors to fully explore the inverted neutrino mass hierarchy with $^{130}$Te and possibly other double beta decay candidate nuclei.

Artusa, D R; Azzolini, O; Balata, M; Banks, T I; Bari, G; Beeman, J; Bellini, F; Bersani, A; Biassoni, M; Brofferio, C; Bucci, C; Cai, X Z; Camacho, A; Canonica, L; Cao, X G; Capelli, S; Carbone, L; Cardani, L; Carrettoni, M; Casali, N; Chiesa, D; Chott, N; Clemenza, M; Copello, S; Cosmelli, C; Cremonesi, O; Creswick, R J; Dafinei, I; Dally, A; Datskov, V; De Biasi, A; Deninno, M M; Di Domizio, S; di Vacri, M L; Ejzak, L; Fang, D Q; Farach, H A; Faverzani, M; Fernandes, G; Ferri, E; Ferroni, F; Fiorini, E; Franceschi, M A; Freedman, S J; Fujikawa, B K; Giachero, A; Gironi, L; Giuliani, A; Goett, J; Gorla, P; Gotti, C; Gutierrez, T D; Haller, E E; Han, K; Heeger, K M; Hennings-Yeomans, R; Huang, H Z; Kadel, R; Kazkaz, K; Keppel, G; Kolomensky, Yu G; Li, Y L; Ligi, C; Liu, X; Ma, Y G; Maiano, C; Maino, M; Martinez, M; Maruyama, R H; Mei, Y; Moggi, N; Morganti, S; Napolitano, T; Nisi, S; Nones, C; Norman, E B; Nucciotti, A; O'Donnell, T; Orio, F; Orlandi, D; Ouellet, J L; Pallavicini, M; Palmieri, V; Pattavina, L; Pavan, M; Pedretti, M; Pessina, G; Pettinacci, V; Piperno, G; Pira, C; Pirro, S; Previtali, E; Rampazzo, V; Rosenfeld, C; Rusconi, C; Sala, E; Sangiorgio, S; Scielzo, N D; Sisti, M; Smith, A R; Taffarello, L; Tenconi, M; Terranova, F; Tian, W D; Tomei, C; Trentalange, S; Ventura, G; Vignati, M; Wang, B S; Wang, H W; Wielgus, L; Wilson, J; Winslow, L A; Wise, T; Woodcraft, A; Zanotti, L; Zarra, C; Zhu, B X; Zucchelli, S

2014-01-01T23:59:59.000Z

170

Scientific Opportunities with the Long-Baseline Neutrino Experiment  

SciTech Connect

In this document, we describe the wealth of science opportunities and capabilities of LBNE, the Long-Baseline Neutrino Experiment. LBNE has been developed to provide a unique and compelling program for the exploration of key questions at the forefront of particle physics. Chief among the discovery opportunities are observation of CP symmetry violation in neutrino mixing, resolution of the neutrino mass hierarchy, determination of maximal or near-maximal mixing in neutrinos, searches for nucleon decay signatures, and detailed studies of neutrino bursts from galactic supernovae. To fulfill these and other goals as a world-class facility, LBNE is conceived around four central components: (1) a new, intense wide-band neutrino source at Fermilab, (2) a fine-grained `near' neutrino detector just downstream of the source, (3) the Sanford Underground Research Facility (SURF) in Lead, South Dakota at an optimal distance (~1300 km) from the neutrino source, and (4) a massive liquid argon time-projection chamber (LArTPC) deployed there as a 'far' detector. The facilities envisioned are expected to enable many other science opportunities due to the high event rates and excellent detector resolution from beam neutrinos in the near detector and atmospheric neutrinos in the far detector. This is a mature, well developed, world class experiment whose relevance, importance, and probability of unearthing critical and exciting physics has increased with time.

Adams, C.; et al.,

2013-07-28T23:59:59.000Z

171

Neutrino Theory  

NLE Websites -- All DOE Office Websites (Extended Search)

operators in the Lagrangian (Majorana mass terms), or both. The ongoing neutrinoless double-beta decay searches may be able to shine light on the matter. But the neutrino sector...

172

Global analysis of the post-SNO solar neutrino data for standard and nonstandard oscillation mechanisms  

Science Journals Connector (OSTI)

What can we learn from solar neutrino observations? Is there any solution to the solar neutrino anomaly which is favored by the present experimental panorama? After SNO results, is it possible to affirm that neutrinos have mass? In order to answer such questions we analyze the current available data from the solar neutrino experiments, including the recent SNO result, in view of many acceptable solutions to the solar neutrino problem based on different conversion mechanisms, for the first time using the same statistical procedure. This allows us to do a direct comparison of the goodness of the fit among different solutions, from which we can discuss and conclude on the current status of each proposed dynamical mechanism. These solutions are based on different assumptions: (a) neutrino mass and mixing, (b) a nonvanishing neutrino magnetic moment, (c) the existence of nonstandard flavor-changing and nonuniversal neutrino interactions, and (d) a tiny violation of the equivalence principle. We investigate the quality of the fit provided by each one of these solutions not only to the total rate measured by all the solar neutrino experiments but also to the recoil electron energy spectrum measured at different zenith angles by the Super-Kamiokande Collaboration. We conclude that several nonstandard neutrino flavor conversion mechanisms provide a very good fit to the experimental data which is comparable with (or even slightly better than) the most famous solution to the solar neutrino anomaly based on the neutrino oscillation induced by mass.

A. M. Gago; M. M. Guzzo; P. C. de Holanda; H. Nunokawa; O. L. G. Peres; V. Pleitez; R. Zukanovich Funchal

2002-03-19T23:59:59.000Z

173

Neutrino Oscillation Experiments at Nuclear Reactors  

E-Print Network (OSTI)

In this paper I give an overview of the status of neutrino oscillation experiments performed using nuclear reactors as sources of neutrinos. I review the present generation of experiments (Chooz and Palo Verde) with baselines of about 1 km as well as the next generation that will search for oscillations with a baseline of about 100 km. While the present detectors provide essential input towards the understanding of the atmospheric neutrino anomaly, in the future, the KamLAND reactor experiment represents our best opportunity to study very small mass neutrino mixing in laboratory conditions. In addition KamLAND with its very large fiducial mass and low energy threshold, will also be sensitive to a broad range of different physics.

Giorgio Gratta

1999-05-06T23:59:59.000Z

174

Neutrino-driven supernova of a low-mass iron-core progenitor boosted by three-dimensional turbulent convection  

E-Print Network (OSTI)

We present the first successful simulation of a neutrino-driven supernova explosion in three dimensions (3D), using the Prometheus-Vertex code with an axis-free Yin-Yang grid and a sophisticated treatment of three-flavor, energy-dependent neutrino transport. The progenitor is a non-rotating, zero-metallicity 9.6 Msun star with an iron core. While in spherical symmetry outward shock acceleration sets in later than 300 ms after bounce, a successful explosion starts at ~130 ms post-bounce in two dimensions (2D). The 3D model explodes at about the same time but with faster shock expansion than in 2D and a more quickly increasing and roughly 10 percent higher explosion energy. The more favorable explosion conditions in 3D are explained by lower temperatures and thus reduced neutrino emission in the cooling layer below the gain radius. This moves the gain radius inward and leads to a bigger mass in the gain layer, whose larger recombination energy boosts the explosion energy in 3D. These differences are caused by less coherent, less massive, and less rapid convective downdrafts associated with post-shock convection in 3D. The less violent impact of these accretion downflows in the cooling layer produces less dissipative heating and therefore diminishes energy losses by neutrino emission. We thus have, for the first time, identified a reduced mass accretion rate, lower infall velocities, and a smaller surface filling factor of convective downdrafts as consequences of 3D postshock turbulence that facilitate neutrino-driven explosions and strengthen them compared to the 2D case.

Tobias Melson; Hans-Thomas Janka; Andreas Marek

2015-01-08T23:59:59.000Z

175

Majorana phases, CP violation, sterile neutrinos and neutrinoless double-beta decay  

SciTech Connect

CP violation plays a crucial role in the generation of the baryon asymmetry in the Universe. Within this context we investigate the possibility of CP violation in the lepton sector caused by Majorana neutrino mixing. Focus is put on the model including 1 sterile neutrino. Both cases of normal and inverted neutrino mass spectrum are considered. We address the question whether the Majorana phases can be measured in the neutrinoless double-beta decay experiments with sensitivity to the effective Majorana neutrino mass of the order of 10{sup ?2} eV.

Babi?, Andrej [Department of Nuclear Physics and Biophysics, Faculty of Mathematics, Physics and Informatics, Comenius University, Mlynsk dolina, 842 48 Bratislava (Slovakia); imkovic, Fedor [Bogoliubov Laboratory of Theoretical Physics, JINR, Joliot-Curie 6, 141980 Dubna, Moscow region, Russia and Institute of Experimental and Applied Physics, Czech Technical University, CZ-128 00 Prague (Czech Republic)

2013-12-30T23:59:59.000Z

176

Atmospheric and Solar neutrinos in the light of the SuperKamiokande results  

E-Print Network (OSTI)

The hierarchy $\\Delta m^2_{atm} \\gg \\Delta m^2_\\odot$ and the large $\\theta_{23}$ mixing angle, as suggested by neutrino oscillation experiments, can be accounted for by a variety of lepton flavour models. A dichotomy emerges: i) Models were all neutrino masses are bounded by $m_{atm}\\equiv (\\Delta m^2_{atm})^{1/2}\\approx 0.03 eV$; ii) Models of quasi-degenerate neutrinos. It is shown how these different patterns of neutrino masses may arise from different lepton flavour symmetries. Physical implications are discussed in the various cases.

Riccardo Barbieri

1999-01-07T23:59:59.000Z

177

Beyond the Standard Model: The Weak Scale, Neutrino Mass, and the Dark Sector  

SciTech Connect

The goal of this proposal was to advance theoretical studies into questions of collider physics at the weak scale, models and signals of dark matter, and connections between neutrino mass and dark energy. The project was a significant success, with a number of developments well beyond what could have been anticipated at the outset. A total of 35 published papers and preprints were produced, with new ideas and signals for LHC physics and dark matter experiments, in particular. A number of new ideas have been found on the possible indirect signals of models of dark matter which relate to the INTEGRAL signal of astrophysical positron production, high energy positrons seen at PAMELA and Fermi, studies into anomalous gamma rays at Fermi, collider signatures of sneutrino dark matter, scenarios of Higgs physics arising in SUSY models, the implications of galaxy cluster surveys for photon-axion conversion models, previously unconsidered collider phenomenology in the form of 'lepton jets' and a very significant result for flavor physics in supersymmetric theories. Progress continues on all fronts, including development of models with dramatic implications for direct dark matter searches, dynamics of dark matter with various excited states, flavor physics, and consequences of modified missing energy signals for collider searches at the LHC.

Weiner, Neal

2010-12-20T23:59:59.000Z

178

Muon neutrino disappearance at MINOS  

SciTech Connect

A strong case has been made by several experiments that neutrinos oscillate, although important questions remain as to the mechanisms and precise values of the parameters. In the standard picture, two parameters describe the nature of how the neutrinos oscillate: the mass-squared difference between states and the mixing angle. The purpose of this thesis is to use data from the MINOS experiment to precisely measure the parameters associated with oscillations first observed in studies of atmospheric neutrinos. MINOS utilizes two similar detectors to observe the oscillatory nature of neutrinos. The Near Detector, located 1 km from the source, observes the unoscillated energy spectrum while the Far Detector, located 735 km away, is positioned to see the oscillation signal. Using the data in the Near Detector, a prediction of the expected neutrino spectrum at the Far Detector assuming no oscillations is made. By comparing this prediction with the MINOS data, the atmospheric mixing parameters are measured to be {Delta}m{sub 32}{sup 2} = 2.45{sub +0.12}{sup -0.12} x 10{sub -3} eV{sup 2} and sin{sup 2}(2{theta}{sub 32}) = 1.00{sub -0.04}{sup +0.00} (> 0.90 at 90% confidence level).

Armstrong, R.; /Indiana U.

2009-08-01T23:59:59.000Z

179

Grand Unified Yukawa Matrix Ansatz: The Standard Model Fermion Mass, Quark Mixing and CP Violation Parameters  

E-Print Network (OSTI)

We propose a new mass matrix ansatz: At the grand unified (GU) scale, the standard model (SM) Yukawa coupling matrix elements are integer powers of the square root of the GU gauge coupling constant \\varepsilon \\equiv \\sqrt{\\alpha_{\\text{GU}}}, multiplied by order unity random complex numbers. It relates the hierarchy of the SM ermion masses and quark mixings to the gauge coupling constants, greatly reducing the SM parameters, and can give good fitting results of the SM fermion mass, quark mixing and CP violation parameters. This is a neat but very effective ansatz.

Yong-Chao Zhang; De-Hai Zhang

2009-10-20T23:59:59.000Z

180

Flavor-changing decays of the Z into heavy neutrinos  

Science Journals Connector (OSTI)

We consider flavor-changing decays of the Z boson to a fourth-generation heavy neutrino and a light neutrino, which are induced at one loop in the standard model. Such decays have a characteristic monojet signature which makes them readily distinguished experimentally, unlike flavor-changing decays involving quarks. Like other such one-loop processes, however, they are very rare when reasonable mixing angles and intermediate fermion masses are considered.

Frederick J. Gilman and Sun H. Rhie

1989-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "neutrino mass mixing" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Solving the Neutrino Mass Mystery using Double Beta Decay. An Examination of the Feasibility of Xennoon Purification and Ion Capture and Release using an Electrostatic Probe  

SciTech Connect

Double beta decay has long been recognized as a useful avenue for the study of electron neutrinos, especially the neutrino mass and its fundamental nature (Majorana or Dirac). Recent neutrino oscillation experiments have provided compelling evidence that the neutrino has mass. The detection of the neutrinoless mode of double beta decay would finally set a lower limit on the mass of the electron neutrino, as well as prove that the neutrino is a Majorana particle (with opposite spin, it is its own anti-particle). The Enriched Xenon Observatory (EXO) project attempts to detect neutrinoless double beta decay using {sup 136}Xe that decays by this process to {sup 136}Ba{sup 2} + e{sup -} + e{sup -}. Perhaps one of the most significant characteristics of this project is the reduction of the background through the identification of the Barium ions for each individual event using laser fluorescence techniques. This project also proposes to collect scintillation light in addition to the ionization electrons in order to further improve energy resolution. Current work at SLAC includes the development of a purification system for xenon, as well as tests for the capture and release of single ions using an electrostatic probe.

Outschoorn, Verena M

2003-09-05T23:59:59.000Z

182

Neutrino-driven supernova of a low-mass iron-core progenitor boosted by three-dimensional turbulent convection  

E-Print Network (OSTI)

We present the first successful simulation of a neutrino-driven supernova explosion in three dimensions (3D), using the Prometheus-Vertex code with an axis-free Yin-Yang grid and a sophisticated treatment of three-flavor, energy-dependent neutrino transport. The progenitor is a non-rotating, zero-metallicity 9.6 Msun star with an iron core. While in spherical symmetry outward shock acceleration sets in later than 300 ms after bounce, a successful explosion starts at ~130 ms post-bounce in two dimensions (2D). The 3D model explodes at about the same time but with faster shock expansion than in 2D and a more quickly increasing and roughly 10 percent higher explosion energy. The more favorable explosion conditions in 3D are explained by lower temperatures and thus reduced neutrino emission in the cooling layer below the gain radius. This moves the gain radius inward and leads to a bigger mass in the gain layer, whose larger recombination energy boosts the explosion energy in 3D. These differences are caused by l...

Melson, Tobias; Marek, Andreas

2015-01-01T23:59:59.000Z

183

Isospin Symmetry Breaking and Octet Baryon Masses due to Their Mixing with Decuplet Baryons  

E-Print Network (OSTI)

We study the isospin symmetry breaking and mass splittings of the eight lowest-lying baryons. We consider three kinds of baryon mass terms, including the bare mass term, the electromagnetic terms and the spontaneous chiral symmetry breaking terms. We include the mixing term between flavor-octet and flavor-decuplet baryons. This assumes that the lowest-lying Sigma and Xi baryons contain a few decuplet components and so are not purely flavor-octet. We achieve a good fitting that the difference between every fitted mass and its experimental value is less than 0.2 MeV.

Hua-Xing Chen

2013-12-05T23:59:59.000Z

184

Radiative Generation of Quark Masses and Mixing Angles in the Two Higgs Doublet Model  

E-Print Network (OSTI)

We present a framework to generate the quark mass hierarchies and mixing angles by extending the Standard Model with one extra Higgs doublet. The charm and strange quark masses are generated by small quantum effects, thus explaining the hierarchy between the second and third generation quark masses. All the mixing angles are also generated by small quantum effects: the Cabibbo angle is generated at zero-th order in perturbation theory, while the remaining off-diagonal entries of the Cabibbo-Kobayashi-Maskawa matrix are generated at first order, hence explaining the observed hierarchy $|V_{ub}|,|V_{cb}|\\ll |V_{us}|$. The values of the radiatively generated parameters depend only logarithmically on the heavy Higgs mass, therefore this framework can be reconciled with the stringent limits on flavor violation by postulating a sufficiently large new physics scale.

Alejandro Ibarra; Ana Solaguren-Beascoa

2014-07-04T23:59:59.000Z

185

Neutrinos from Gamma Ray Bursts  

E-Print Network (OSTI)

We show that the detection of neutrinos from a typical gamma ray burst requires a kilometer-scale detector. We argue that large bursts should be visible with the neutrino telescopes under construction. We emphasize the 3 techniques by which neutrino telescopes can perform this search: by triggering on i) bursts of muons from muon neutrinos, ii) muons from air cascades initiated by high energy gamma rays and iii) showers made by relatively low energy ($\\simeq 100\\,\\mev$) electron neutrinos. Timing of neutrino-photon coincidences may yield a measurement of the neutrino mass to order $10^{-5}$~eV, an interesting range in light of the solar neutrino anomaly.

F. Halzen; G. Jaczko

1996-02-07T23:59:59.000Z

186

Probing neutrino oscillations from supernovae shock waves via the IceCube detector  

Science Journals Connector (OSTI)

The time dependent neutrino oscillation signals due to the passage of a shock wave through the supernovae are analyzed for the case of three active neutrinos and also for the case that there are two additional sterile neutrinos. It is shown that, even without flavor identification and energy measurement, detailed information about the masses and mixing angles of the neutrinos may be obtained with a detector with excellent time resolution such as IceCube. Such a signal would also give important information about the nature of the shock wave within the supernovae.

Sandhya Choubey; N. P. Harries; G. G. Ross

2006-09-25T23:59:59.000Z

187

Massive neutrinos and cosmology  

E-Print Network (OSTI)

The present experimental results on neutrino flavour oscillations provide evidence for non-zero neutrino masses, but give no hint on their absolute mass scale, which is the target of beta decay and neutrinoless double-beta decay experiments. Crucial complementary information on neutrino masses can be obtained from the analysis of data on cosmological observables, such as the anisotropies of the cosmic microwave background or the distribution of large-scale structure. In this review we describe in detail how free-streaming massive neutrinos affect the evolution of cosmological perturbations. We summarize the current bounds on the sum of neutrino masses that can be derived from various combinations of cosmological data, including the most recent analysis by the WMAP team. We also discuss how future cosmological experiments are expected to be sensitive to neutrino masses well into the sub-eV range.

Julien Lesgourgues; Sergio Pastor

2006-05-29T23:59:59.000Z

188

Neutrino mass, sneutrino dark matter and signals of lepton flavor violation in the MRSSM  

Science Journals Connector (OSTI)

We study the phenomenology of mixed-sneutrino dark matter in the Minimal R-symmetric Supersymmetric Standard Model (MRSSM). Mixed sneutrinos fit naturally within the MRSSM, as the smallness (or absence) of neutri...

Abhishek Kumar; David Tucker-Smith; Neal Weiner

2010-09-01T23:59:59.000Z

189

Current trends in non-accelerator particle physics: 1, Neutrino mass and oscillation. 2, High energy neutrino astrophysics. 3, Detection of dark matter. 4, Search for strange quark matter. 5, Magnetic monopole searches  

SciTech Connect

This report is a compilation of papers reflecting current trends in non-accelerator particle physics, corresponding to talks that its author was invited to present at the Workshop on Tibet Cosmic Ray Experiment and Related Physics Topics held in Beijing, China, April 4--13, 1995. The papers are entitled `Neutrino Mass and Oscillation`, `High Energy Neutrino Astrophysics`, `Detection of Dark Matter`, `Search for Strange Quark Matter`, and `Magnetic Monopole Searches`. The report is introduced by a survey of the field and a brief description of each of the author`s papers.

He, Yudong [California Univ., Berkeley, CA (United States)]|[Lawrence Berkeley Lab., CA (United States)

1995-07-01T23:59:59.000Z

190

THERMOHALINE MIXING: DOES IT REALLY GOVERN THE ATMOSPHERIC CHEMICAL COMPOSITION OF LOW-MASS RED GIANTS?  

SciTech Connect

First results of our three-dimensional numerical simulations of thermohaline convection driven by {sup 3}He burning in a low-mass red giant branch (RGB) star at the bump luminosity are presented. They confirm our previous conclusion that this convection has a mixing rate that is a factor of 50 lower than the observationally constrained rate of RGB extra-mixing. It is also shown that the large-scale instabilities of the salt-fingering mean field (those of the Boussinesq and advection-diffusion equations averaged over length and timescales of many salt fingers), which have been observed to increase the rate of oceanic thermohaline mixing up to one order of magnitude, do not enhance the RGB thermohaline mixing. We speculate on possible alternative solutions of the problem of RGB extra-mixing, among which the most promising one that is related to thermohaline mixing takes advantage of the shifting of the salt-finger spectrum toward larger diameters by toroidal magnetic field.

Denissenkov, Pavel A. [Department of Physics and Astronomy, University of Victoria, P.O. Box 3055, Victoria, BC, V8W 3P6 (Canada); Merryfield, William J., E-mail: pavel.denisenkov@gmail.com, E-mail: bill.merryfield@ec.gc.ca [Canadian Centre for Climate Modelling and Analysis, University of Victoria, P.O. Box 3065, Victoria, BC, V8W 3V6 (Canada)

2011-01-20T23:59:59.000Z

191

Neutrino Oscillations in 1. The Study of Neutrino Oscillations  

E-Print Network (OSTI)

... Currently there are three oscillation signal regions: #15; LSND #23; e ! #23; #22; ,#23; e ! #23; #22; separately #15; Atmospheric Neutrinos #23; #22; + #23; #22; disappearance #15; Solar Neutrinos #23; e is combination of two e#11;ects Proposed Matrixes for Neutrino Mixing (#23; 1 ; #23; 2 ; #23; 3 ) = M(#23; e

192

Light Sterile Neutrino in the Minimal Extended Seesaw  

E-Print Network (OSTI)

Motivated by the recent observations on sterile neutrinos, we present a minimal extension of the canonical type-I seesaw by adding one extra singlet fermion. After the decoupling of right-handed neutrinos, an eV-scale mass eigenstate is obtained without the need of artificially inserting tiny mass scales or Yukawa couplings for sterile neutrinos. In particular, the active-sterile mixing is predicted to be of the order of 0.1. Moreover, we show a concrete flavor A_4 model, in which the required structures of the minimal extended seesaw are realized. We also comment on the feasibility of accommodating a keV sterile neutrino as an attractive candidate for warm dark matter.

He Zhang

2011-10-31T23:59:59.000Z

193

Solar Neutrino Matter Effects Redux  

E-Print Network (OSTI)

Following recent low-threshold analysis of the Sudbury Neutrino Observatory and asymmetry measurements of the BOREXINO Collaboration of the solar neutrino flux, we revisit the analysis of the matter effects in the Sun. We show that solar neutrino data constrains the mixing angle $\\theta_{13}$ poorly and that subdominant Standard Model effects can mimic the effects of the physics beyond the Standard Model.

A. B. Balantekin; A. Malkus

2011-12-19T23:59:59.000Z

194

Realistic Earth matter effects and a method to acquire information about small ?_{13} in the detection of supernova neutrinos  

E-Print Network (OSTI)

In this paper, we first calculate the realistic Earth matter effects in the detection of type II supernova neutrinos at the Daya Bay reactor neutrino experiment which is currently under construction. It is found that the Earth matter effects depend on the neutrino incident angle $\\theta$, the neutrino mass hierarchy $\\Delta m_{31}^{2}$, the crossing probability at the high resonance region inside the supernova, $P_{H}$, the neutrino temperature, $T_{\\alpha}$, and the pinching parameter in the neutrino spectrum, $\\eta_{\\alpha}$. We also take into account the collective effects due to neutrino-neutrino interactions inside the supernova. With the expression for the dependence of $P_H$ on the neutrino mixing angle $\\theta_{13}$, we obtain the relations between $\\theta_{13}$ and the event numbers for various reaction channels of supernova neutrinos. Using these relations, we propose a possible method to acquire information about $\\theta_{13}$ smaller than $1.5^\\circ$. Such a sensitivity cannot yet be achieved by the Daya Bay reactor neutrino experiment which has a sensitivity of the order of $\\theta_{13}\\sim 3^\\circ$. Furthermore, we apply this method to other neutrino experiments, i.e. Super-K, SNO, KamLAND, LVD, MinBooNE, Borexino, and Double-Chooz. We also study the energy spectra of the differential event numbers, ${\\rm d}N/{\\rm d}E$.

Xin-Heng Guo; Ming-Yang Huang; Bing-Lin Young

2009-04-14T23:59:59.000Z

195

Seismic diagnostics of mixing beyond the convective core in intermediate mass main-sequence stars  

E-Print Network (OSTI)

We study prospects for seismic sounding the layer of a partial mixing above the convective core in main-sequence stars with masses in the 1.2 -- 1.9 solar mass range. There is an initial tendency to an increase of convective core mass in such stars and this leads to ambiguities in modeling. Solar-like oscillations are expected to be excited in such objects. Frequencies of such oscillations provide diagnostics, which are sensitive to the structure of the innermost part of the star and they are known as the small separations. We construct evolutionary models of stars in this mass range assuming various scenarios for element mixing, which includes formation of element abundance jumps, as well as semiconvective and overshooting layers. We find that the three point small separations employing frequencies of radial and dipole modes provide the best probe of the element distribution above the convective core. With expected accuracy of frequency measurement from the space experiments, a discrimination between various scenarios should be possible.

B. L. Popielski; W. A. Dziembowski

2005-05-25T23:59:59.000Z

196

High Precision Atomic Mass Spectrometry with Applications to Neutrino Physics, Fundamental Constants and Physical Chemistry.  

E-Print Network (OSTI)

?? The Florida State University single-ion cryogenic Penning trap mass spectrometer has been used to precisely measure the masses of the doublets 76Ge/76Se and 74Ge/74Se (more)

Mount, Brianna Jane

2010-01-01T23:59:59.000Z

197

Deformation effects and neutrinoless positron ?? decay of Ru96, Pd102, Cd106, Xe124, Ba130, and Dy156 isotopes within a mechanism involving Majorana neutrino mass  

Science Journals Connector (OSTI)

The (?+?+)0? and (??+)0? modes of Ru96, Pd102, Cd106, Xe124, Ba130, and Dy156 isotopes are studied in the projected Hartree-Fock-Bogoliubov framework for the 0+?0+ transition. The reliability of the intrinsic wave functions required to study these decay modes has been established in our earlier works by obtaining an overall agreement between the theoretically calculated spectroscopic properties, namely yrast spectra, reduced B(E2:0+?2+) transition probabilities, quadrupole moments Q(2+) and gyromagnetic factors g(2+), and the available experimental data in the parent and daughter even-even nuclei. In the present work, the required nuclear transition matrix elements are calculated in the Majorana neutrino mass mechanism using the same set of intrinsic wave functions as used to study the two neutrino positron double-? decay modes. Limits on effective light neutrino mass ?m?? and effective heavy neutrino mass ?MN? are extracted from the observed limits on half-lives T1/20?(0+?0+) of (?+?+)0? and (??+)0? modes. We also investigate the effect of quadrupolar correlations vis-a-vis deformation on nuclear transition matrix elements (NTMEs) required to study the (?+?+)0? and (??+)0? modes.

P. K. Rath, R. Chandra, K. Chaturvedi, P. K. Raina, and J. G. Hirsch

2009-10-06T23:59:59.000Z

198

Uncertainties in nuclear transition matrix elements for neutrinoless ?? decay: The heavy Majorana neutrino mass mechanism  

Science Journals Connector (OSTI)

Employing four different parametrizations of the pairing plus the multipolar type of effective two-body interaction and three different parametrizations of the Jastrow type of short-range correlations, the uncertainties in the nuclear transition matrix elements MN0? due to the exchange of heavy Majorana neutrino for the 0+?0+ transition of neutrinoless double beta decay of 94Zr, 96Zr, 98Mo, 100Mo, 104Ru, 110Pd, 128,130Te, and 150Nd isotopes in the PHFB model are estimated to be around 35%. Excluding the nuclear transition matrix elements calculated with the Miller-Spencer parametrization of Jastrow short-range correlations, the uncertainties are found to be smaller than 20%.

P. K. Rath, R. Chandra, P. K. Raina, K. Chaturvedi, and J. G. Hirsch

2012-01-11T23:59:59.000Z

199

Quasi-energy-independent solar neutrino transitions  

E-Print Network (OSTI)

Current solar, atmospheric, and reactor neutrino data still allow oscillation scenarios where the squared mass differences are all close to 10^-3 eV^2, rather than being hierarchically separated. For solar neutrinos, this situation (realized in the upper part of the so-called large-mixing angle solution) implies adiabatic transitions which depend weakly on the neutrino energy and on the matter density, as well as on the ``atmospheric'' squared mass difference. In such a regime of ``quasi-energy-independent'' (QEI) transitions, intermediate between the more familiar ``Mikheyev-Smirnov-Wolfenstein'' (MSW) and energy-independent (EI) regimes, we first perform analytical calculations of the solar nu_e survival probability at first order in the matter density, beyond the usual hierarchical approximations. We then provide accurate, generalized expressions for the solar neutrino mixing angles in matter, which reduce to those valid in the MSW, QEI and EI regimes in appropriate limits. Finally, a representative QEI scenario is discussed in some detail.

G. L. Fogli; E. Lisi; A. Palazzo

2001-05-09T23:59:59.000Z

200

Higgs boson exempt no-scale supersymmetry with a neutrino seesaw mechanism: Implications for lepton flavor violation and leptogenesis  

SciTech Connect

Motivated by the observation of neutrino oscillations, we extend the Higgs boson exempt no-scale supersymmetry model by adding three heavy right-handed neutrino chiral supermultiplets to generate the light neutrino masses and mixings. The neutrino Yukawa couplings can induce new lepton-flavor violating couplings among the soft terms in the course of renormalization group running down from the boundary scale. We study the effects this has on the predictions for low-energy probes of lepton-flavor violation (LFV). Heavy right-handed neutrinos also provide a way to generate the baryon asymmetry through leptogenesis. We find that consistency with LFV and leptogenesis puts strong requirements on either the form of the Yukawa mass matrix or the smallness of the Higgs up soft mass. In all cases, we generically expect that new physics LFV is nonzero and can be found in a future experiment.

Chun, Eung Jin [Korean Institute for Advanced Study (KIAS), Hoegiro 87, Dongdaemun-gu Seoul 130-722 (Korea, Republic of); Evans, Jason L. [Michigan Center for Theoretical Physics (MCTP), USAUniversity of Michigan, Ann Arbor, Michigan 48109 (United States); Morrissey, David E. [Michigan Center for Theoretical Physics (MCTP), USAUniversity of Michigan, Ann Arbor, Michigan 48109 (United States); Kavli Institute for Theoretical Physics, University of California, Santa Barbara, California 93106-4030 (United States); Wells, James D. [Michigan Center for Theoretical Physics (MCTP), USAUniversity of Michigan, Ann Arbor, Michigan 48109 (United States); CERN, Theory Division, CH-1211 Geneva 23 (Switzerland); Kavli Institute for Theoretical Physics, University of California, Santa Barbara, California 93106-4030 (United States)

2009-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "neutrino mass mixing" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

arXiv:0706.1732v2[hep-ph]11Jul2007 NUHEP-TH/07-06 GeV Seesaw, Accidentally Small Neutrino Masses, and Higgs Decays to Neutrinos  

E-Print Network (OSTI)

mixing and will provide important input for interpretation of next-generation neutrinoless double beta decay experiments. Measurement of the mass hierarchy is important input to the search for leptonic CP

202

Probing Neutrino Dark Energy with Extremely High-Energy Cosmic Neutrinos  

E-Print Network (OSTI)

Recently, a new non-Standard Model neutrino interaction mediated by a light scalar field was proposed, which renders the big-bang relic neutrinos of the cosmic neutrino background a natural dark energy candidate, the so-called Neutrino Dark Energy. As a further consequence of this interaction, the neutrino masses become functions of the neutrino energy densities and are thus promoted to dynamical, time/redshift dependent quantities. Such a possible neutrino mass variation introduces a redshift dependence into the resonance energies associated with the annihilation of extremely high-energy cosmic neutrinos on relic anti-neutrinos and vice versa into Z-bosons. In general, this annihilation process is expected to lead to sizeable absorption dips in the spectra to be observed on earth by neutrino observatories operating in the relevant energy region above 10^13 GeV. In our analysis, we contrast the characteristic absorption features produced by constant and varying neutrino masses, including all thermal background effects caused by the relic neutrino motion. We firstly consider neutrinos from astrophysical sources and secondly neutrinos originating from the decomposition of topological defects using the appropriate fragmentation functions. On the one hand, independent of the nature of neutrino masses, our results illustrate the discovery potential for the cosmic neutrino background by means of relic neutrino absorption spectroscopy. On the other hand, they allow to estimate the prospects for testing its possible interpretation as source of Neutrino Dark Energy within the next decade by the neutrino observatories ANITA and LOFAR.

Andreas Ringwald; Lily Schrempp

2006-06-13T23:59:59.000Z

203

Day-night asymmetry of high and low energy solar neutrino events in Super-Kamiokande and in the Sudbury Neutrino Observatory  

E-Print Network (OSTI)

In the context of solar neutrino oscillations among active states, we briefly discuss the current likelihood of Mikheyev-Smirnov-Wolfenstein (MSW) solutions to the solar neutrino problem, which appear to be currently favored at large mixing, where small Earth regeneration effects might still be observable in Super-Kamiokande (SK) and in the Sudbury Neutrino Observatory (SNO). We point out that, since such effects are larger at high (low) solar neutrino energies for high (low) values of the mass square difference \\delta m^2, it may be useful to split the night-day rate asymmetry in two separate energy ranges. We show that the difference \\Delta of the night-day asymmetry at high and low energy may help to discriminate the two large-mixing solutions at low and high \\delta m^2 through a sign test, both in SK and in SNO, provided that the sensitivity to \\Delta can reach the (sub)percent level.

G. L. Fogli; E. Lisi; D. Montanino; A. Palazzo

2000-08-01T23:59:59.000Z

204

Earth Matter Effect on Democratic Neutrinos  

E-Print Network (OSTI)

The neutrino propagation through the Earth is investigated in the framework of the democratic neutrino theory. In this theory the neutrino mixing angle theta-1-3 is approximately determined, which allows one to make a well defined neutrino oscillogram driven by the 1-3 mixing in the matter of the Earth. Significant differences in this oscillogram from the case of models with relatively small theta-1-3 are discussed.

Dmitry Zhuridov

2014-08-30T23:59:59.000Z

205

Improved Description of One- and Two-Hole States after Electron Capture in 163 Holmium and the Determination of the Neutrino Mass  

E-Print Network (OSTI)

The atomic pair 163 Holmium and 163 Dysprosium$ seems due to the small Q value of about 2.3 to 2.8 keV the best case to determine the neutrino mass by electron capture. The bolometer spectrum measures the full deexcitation energy of Dysprosium by X rays, by Auger electrons and by the recoil of Holmium. The spectrum has an upper energy limit given by the Q value minus the neutrino mass. Till now this spectrum has been calculated allowing in Dysprosium excitations with 3s1/2, 3p1/2, 4s1/2, 4p1/2, 5s1/2, 5p1/2 holes only. Robertson calculated recently also the spectrum with two electron hole excitations in Dy. He took the probability for the excitation for the second electron hole from work of Carlson and Nestor for Z=54 Xenon. He claims, that the bolometer spectrum with two holes is "not well enough understood to permit a sensitive determination of the neutrino mass in this way." The purpose of the present work is to determine the theoretical bolometer spectrum with two hole excitations more reliably. In additi...

Faessler, Amand

2015-01-01T23:59:59.000Z

206

Lepton textures and neutrino oscillations  

E-Print Network (OSTI)

Systematic analyses of the textures arising in lepton mass matrices have been carried out using unitary transformations and condition of naturalness for the Dirac and Majorana neutrino possibilities. It is observed that the recent three neutrino oscillation data together with the effective mass in neutrinoless double beta decay provide vital clues in predicting the general structures of these lepton mass matrices.

Verma, Rohit

2014-01-01T23:59:59.000Z

207

Search for Heavy Right Handed Neutrinos at the FCC-ee  

E-Print Network (OSTI)

The Standard Model of particle physics is still lacking an understanding of the generation and nature of neutrino masses. A favorite theoretical scenario (the see-saw mechanism) is that both Dirac and Majorana mass terms are present, leading to the existence of heavy partners of the light neutrinos, presumably massive and nearly sterile. These heavy neutrinos can be searched for at high energy lepton colliders of very high luminosity, such as the Future electron-positron e+e- Circular Collider, FCC-ee (TLEP), presently studied within the Future Circular Collider design study at CERN, as a possible first step. A first look at sensitivities, both from neutrino counting and from direct search for heavy neutrino decay, are presented. The number of neutrinos should be measurable with a precision between 0.001 - 0.0004, while the direct search appears very promising due to the long lifetime of heavy neutrinos for small mixing angles. A sensitivity down to a heavy-light mixing of 10^{-12} is obtained, covering a lar...

Blondel, Alain; Serra, N; Shaposhnikov, M

2014-01-01T23:59:59.000Z

208

The use the a high intensity neutrino beam from the ESS proton linac for measurement of neutrino CP violation and mass hierarchy  

E-Print Network (OSTI)

It is proposed to complement the ESS proton linac with equipment that would enable the production, concurrently with the production of the planned ESS beam used for neutron production, of a 5 MW beam of 10$^{23}$ 2.5 GeV protons per year in microsecond short pulses to produce a neutrino Super Beam, and to install a megaton underground water Cherenkov detector in a mine to detect $\

Baussan, E; Ekelof, T; Martinez, E Fernandez; Ohman, H; Vassilopoulos, N

2012-01-01T23:59:59.000Z

209

The use of a high intensity neutrino beam from the ESS proton linac for measurement of neutrino CP violation and mass hierarchy  

E-Print Network (OSTI)

It is proposed to complement the ESS proton linac with equipment that would enable the production, concurrently with the production of the planned ESS beam used for neutron production, of a 5 MW beam of 10$^{23}$ 2.5 GeV protons per year in microsecond short pulses to produce a neutrino Super Beam, and to install a megaton underground water Cherenkov detector in a mine to detect $\

E. Baussan; M. Dracos; T. Ekelof; E. Fernandez Martinez; H. Ohman; N. Vassilopoulos

2013-02-09T23:59:59.000Z

210

Hadronic EDMs in SUSY SU(5) GUTs with Right-handed Neutrinos  

E-Print Network (OSTI)

We discuss hadronic EDM constraints on the neutrino sector in the SUSY SU(5) GUT with the right-handed neutrinos. The hadronic EDMs are sensitive to the right-handed down-type squark mixings, especially between the second and third generations and between the first and third ones, compared with the other low-energy observables, and the flavor mixings are induced by the neutrino Yukawa interaction. The current experimental bound of the neutron EDM may imply that the right-handed tau neutrino mass is smaller than about 10^{14} GeV in the minimal supergravity scenario, and it may be improved furthermore in future experiments, such as the deuteron EDM measurement.

Junji Hisano; Mitsuru Kakizaki; Minoru Nagai; Yasuhiro Shimizu

2004-07-15T23:59:59.000Z

211

Constraints on Weakly Mixed Sterile Neutrinos in the Light of SNO Salt Phase and 766.3 Ty KamLAND Data  

E-Print Network (OSTI)

The possibility of flavor transitions into sterile neutrinos (accompanying the dominant LMA transitions) in the solar boron neutrino flux has been examined in a scenario proposed by Hollanda and Smirnov to overcome some generic problems of the pure LMA scenario. It is found that the most recent SNO salt phase solar neutrino data and the KamLAND 766.3 Ty spectral data, allow for a significant sterile presence in the solar boron neutrino flux reaching the earth.

S. Dev; Sanjeev Kumar

2005-04-26T23:59:59.000Z

212

Solar-neutrino problem: Some old solutions reexamined  

Science Journals Connector (OSTI)

Recent experimental data confirm the solar-neutrino problem and imply new neutrino physics. We review some of the less discussed proposals to solve this problem: (1) maximal vacuum mixing of three neutrino flavors, (2) vacuum oscillation of two neutrino flavors, and (3) neutrino decay. Each of these three solutions can fit the Cl37 and Kamiokande-II solar-neutrino-flux measurements. Their implications for the continuing Ga71 experiments and for other, future experiments are discussed.

Andy Acker; Sandip Pakvasa; James Pantaleone

1991-03-15T23:59:59.000Z

213

Probing neutrino physics at LHC through R-parity breaking supersymmetry  

E-Print Network (OSTI)

R-parity conservation is an ad-hoc assumption in the most popular versions of supersymmetric scenarios. Hence R-parity violation (RPV) not only is allowed but, if induced by bilinear terms (bRPV), it also provides an explanation for the observed neutrino masses and mixing. Here bRPV models are discussed, giving emphasis on the $\\mu$-from-$\

Vasiliki A. Mitsou

2014-01-20T23:59:59.000Z

214

Penetration of Convective Envelope into Stellar Core and Existence of Neutrino Loss  

Science Journals Connector (OSTI)

......the products of Penetration of Convective Envelope...convective mixing for any rate of the neutrino...superadiabaticity is determined Penetration of Convective Envelope...used.15> 459 the rate of Since the main...energy generation rate is sensitive to...smaller mass stars, penetration of convective envelope......

Ken'ichi Nomoto

1974-08-01T23:59:59.000Z

215

Investigation of Neutrino Properties in Experiments at Nuclear Reactors: Present Status and Prospects  

E-Print Network (OSTI)

This paper was submitted in Russian edition of Journal Physics of Atomic Nuclei in 2001. The present status of experiments that are being performed at nuclear reactors in order to seek the neutrino masses, mixing, and magnetic moments, whose discovery would be a signal of the existence of physics beyond the Standard Model, is considered, along with their future prospects.

L. A. Mikaelyan

2002-10-03T23:59:59.000Z

216

Imprints of CP violation induced by sterile neutrinos in T2K  

E-Print Network (OSTI)

We investigate the impact of light ($\\sim$ eV) sterile neutrinos in the long-baseline experiment T2K. We show that, within the 3+1 scheme, for mass-mixing parameters suggested by the short-baseline anomalies, the interference among the sterile and the atmospheric oscillation frequencies induces a new term in the $\

N. Klop; A. Palazzo

2015-02-10T23:59:59.000Z

217

What we can learn from atmospheric neutrinos  

E-Print Network (OSTI)

Physics potential of future measurements of atmospheric neutrinos is explored. Observation of $\\Delta m^2_{21}$ driven sub-dominant effects and $\\theta_{13}$ driven large matter effects in atmospheric neutrinos can be used to study the deviation of $\\theta_{23}$ from maximality and its octant. Neutrino mass hierarchy can be determined extremely well due to the large matter effects. New physics can be constrained both in standard atmospheric neutrino experiments as well as in future neutrino telescopes.

Sandhya Choubey

2006-09-19T23:59:59.000Z

218

Coherence condition for resonant neutrino oscillation  

Science Journals Connector (OSTI)

We study the coherence condition for a neutrino to keep coherence between the effective mass eigenstates in the presence of matter and examine whether or not resonant neutrino oscillation (RNO) happens in the cases of solar and SN 1987A neutrinos. As a result, it becomes evident that RNO is possible in the solar-neutrino case but impossible in the SN 1987A neutrino case.

Hajime Anada and Haruhiko Nishimura

1990-04-15T23:59:59.000Z

219

Energy Loss of Neutrinos in 20 M{sub {center_dot}} and 40 M{sub {center_dot}} Massive Stars  

SciTech Connect

The progress from the theoretical and experimental aspects in neutrino physics shines light into neutrino physics as well as in astrophysics. It is known that when neutrinos pass through a medium, the neutrinos interact with electrons before emerging from the stars with an effective potential energy produced due to coherent forward scatterings that occurred in the medium. This potential engenders significant changes in the neutrino masses and their mixing in the medium. Thus electron neutrinos would oscillate into different mass eigenstate and this is dependent on the energy of the neutrinos. Some of the energy will be lost in the coherent scattering with the electrons by the charged current interaction. We have calculated the energy loss of the neutrinos by using a stopping power equation for both rotating and non-rotating 20 M{sub {center_dot}} and 40 M{sub {center_dot}} stars. The total energy loss of neutrinos depends on the electron density in the stars and on the survival probability of the electron neutrino. For high electron density profile and the survival probability, the energy loss will be significant.

Sofiah Ahmad, Nor; Yusof, Norhasliza; Abu Kassim, Hasan [Department of Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia)

2011-03-30T23:59:59.000Z

220

Quantum Coherence of Relic Neutrinos  

Science Journals Connector (OSTI)

We argue that in at least a portion of the history of the Universe the relic background neutrinos are spatially extended, coherent superpositions of mass states. We show that an appropriate quantum mechanical treatment affects the neutrino mass values derived from cosmological data. The coherence scale of these neutrino flavor wave packets can be an appreciable fraction of the causal horizon size, raising the possibility of spacetime curvature-induced decoherence.

George M. Fuller and Chad T. Kishimoto

2009-05-22T23:59:59.000Z

Note: This page contains sample records for the topic "neutrino mass mixing" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Atmospheric Neutrinos  

E-Print Network (OSTI)

This paper is a brief overview of the theory and experimental data of atmospheric neutrino production at the fiftieth anniversary of the experimental discovery of neutrinos.

Thomas K. Gaisser

2006-12-11T23:59:59.000Z

222

Prospects for the measurement of muon-neutrino disappearance at the FNAL-Booster  

E-Print Network (OSTI)

Neutrino physics is nowadays receiving more and more attention as a possible source of information for the long-standing problem of new physics beyond the Standard Model. The recent measurement of the mixing angle $\\theta_{13}$ in the standard mixing oscillation scenario encourages us to pursue the still missing results on leptonic CP violation and absolute neutrino masses. However, puzzling measurements exist that deserve an exhaustive evaluation. The NESSiE Collaboration has been setup to undertake conclusive experiments to clarify the muon-neutrino disappearance measurements at small $L/E$, which will be able to put severe constraints to models with more than the three-standard neutrinos, or even to robustly measure the presence of a new kind of neutrino oscillation for the first time. To this aim the use of the current FNAL-Booster neutrino beam for a Short-Baseline experiment has been carefully evaluated. This proposal refers to the use of magnetic spectrometers at two different sites, Near and Far. Their positions have been extensively studied, together with the possible performances of two OPERA-like spectrometers. The proposal is constrained by availability of existing hardware and a time-schedule compatible with the CERN project for a new more performant neutrino beam, which will nicely extend the physics results achievable at the Booster. The possible FNAL experiment will allow to clarify the current $\

A. Anokhina; A. Bagulya; M. Benettoni; P. Bernardini; R. Brugnera; M. Calabrese; A. Cecchetti; S. Cecchini; M. Chernyavskiy; P. Creti; F. Dal Corso; O. Dalkarov; A. Del Prete; G. De Robertis; M. De Serio; L. Degli Esposti; D. Di Ferdinando; S. Dusini; T. Dzhatdoev; C. Fanin; R. A. Fini; G. Fiore; A. Garfagnini; S. Golovanov; M. Guerzoni; B. Klicek; U. Kose; K. Jakovcic; G. Laurent; I. Lippi; F. Loddo; A. Longhin; M. Malenica; G. Mancarella; G. Mandrioli; A. Margiotta; G. Marsella; N. Mauri; E. Medinaceli; A. Mengucci; R. Mingazheva; O. Morgunova; M. T. Muciaccia; M. Nessi; D. Orecchini; A. Paoloni; G. Papadia; L. Paparella; L. Pasqualini; A. Pastore; L. Patrizii; N. Polukhina; M. Pozzato; M. Roda; T. Roganova; G. Rosa; Z. Sahnoun; S. Simone; C. Sirignano; G. Sirri; M. Spurio; L. Stanco; N. Starkov; M. Stipcevic; A. Surdo; M. Tenti; V. Togo; M. Ventura; M. Vladymyrov

2014-04-09T23:59:59.000Z

223

Fourth generation neutrinos and neutrino induced hadron production in the resonance region.  

E-Print Network (OSTI)

??We investigate two aspects in neutrino physics. First, we consider the extension of the standard model by a fourth fermion generation. Allowing finite mixing of (more)

Schalla, Dario

2013-01-01T23:59:59.000Z

224

Neutron star accretion and the neutrino fireball  

SciTech Connect

The mixing necessary to explain the Fe'' line widths and possibly the observed red shifts of 1987A is explained in terms of large scale, entropy conserving, up and down flows (calculated with a smooth particle 2-D code) taking place between the neutron star and the explosion shock wave due to the gravity and neutrino deposition. Depending upon conditions of entropy and mass flux further accretion takes place in single events, similar to relaxation oscillator, fed by the downward flows of low entropy matter. The shock, in turn, is driven by the upflow of the buoyant high entropy bubbles. Some accretion events will reach a temperature high enough to create a neutrino fireball,'' a region hot enough, 11 Mev, so as to be partially opaque to its own (neutrino) radiation. The continuing neutrino deposition drives the explosion shock until the entropy of matter flowing downwards onto the neutron star is high enough to prevent further accretion. This process should result in a robust supernova explosion.

Colgate, S.A. (Los Alamos National Lab., NM (United States)); Herant, M.E. (Harvard-Smithsonian Center for Astrophysics, Cambridge, MA (United States)); Benz, W. (Steward Observatory, Tucson, AZ (United States))

1991-11-26T23:59:59.000Z

225

Neutron star accretion and the neutrino fireball  

SciTech Connect

The mixing necessary to explain the ``Fe`` line widths and possibly the observed red shifts of 1987A is explained in terms of large scale, entropy conserving, up and down flows (calculated with a smooth particle 2-D code) taking place between the neutron star and the explosion shock wave due to the gravity and neutrino deposition. Depending upon conditions of entropy and mass flux further accretion takes place in single events, similar to relaxation oscillator, fed by the downward flows of low entropy matter. The shock, in turn, is driven by the upflow of the buoyant high entropy bubbles. Some accretion events will reach a temperature high enough to create a neutrino ``fireball,`` a region hot enough, 11 Mev, so as to be partially opaque to its own (neutrino) radiation. The continuing neutrino deposition drives the explosion shock until the entropy of matter flowing downwards onto the neutron star is high enough to prevent further accretion. This process should result in a robust supernova explosion.

Colgate, S.A. [Los Alamos National Lab., NM (United States); Herant, M.E. [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA (United States); Benz, W. [Steward Observatory, Tucson, AZ (United States)

1991-11-26T23:59:59.000Z

226

Neutrino Physics  

DOE R&D Accomplishments (OSTI)

The prediction and verification of the neutrino are reviewed, together with the V A theory for its interactions (particularly the difficulties with the apparent existence of two neutrinos and the high energy cross section). The Brookhaven experiment confirming the existence of two neutrinos and the cross section increase with momentum is then described, and future neutrino experiments are considered. (D.C.W.)

Lederman, L. M.

1963-01-09T23:59:59.000Z

227

Neutrino oscillations  

Science Journals Connector (OSTI)

...the energy released in the nuclear transition. If neutrinos have...momentum p is produced in a nuclear b-decay. At time t = 0 the...neutrino oscillations in x 3 only vacuum oscillations were considered...of muon neutrinos from the accelerator complex at Fermilab. The neutrinos...

2002-01-01T23:59:59.000Z

228

A combined beta-beam and electron capture neutrino experiment  

E-Print Network (OSTI)

The next generation of long baseline neutrino experiments will aim at determining the value of the unknown mixing angle, theta_{13}, the type of neutrino mass hierarchy and the presence of CP-violation in the lepton sector. Beta-beams and electron capture experiments have been studied as viable candidates for long baseline experiments. They use a very clean electron neutrino beam from the beta-decays or electron capture decays of boosted ions. In the present article we consider an hybrid setup which combines a beta-beam with an electron capture beam by using boosted Ytterbium ions. We study the sensitivity to the CP-violating phase delta and the theta_{13} angle, the CP-discovery potential and the reach to determine the type of neutrino mass hierarchy for this type of long baseline experiment. The analysis is performed for different neutrino beam energies and baselines. Finally, we also discuss how the results would change if a better knowledge of some of the assumed parameters was achieved by the time this experiment could take place.

J. Bernabeu; C. Espinoza; C. Orme; S. Palomares-Ruiz; S. Pascoli

2009-02-27T23:59:59.000Z

229

Effect of $^{12}C+$ $^{12}C$ Reaction & Convective Mixing on the Progenitor Mass of ONe White Dwarfs  

E-Print Network (OSTI)

Stars in the mass range ~8 - 12 $M_{\\odot }$ are the most numerous massive stars. This mass range is critical because it may lead to supernova (SN) explosion, so it is important for the production of heavy elements and the chemical evolution of the galaxy. We investigate the critical transition mass ($M_{up}$), which is the minimum initial stellar mass that attains the conditions for hydrostatic carbon burning. Stars of masses carbon in a partially degenerate CO core and form electron degenerate ONe cores. These stars evolve to the Super AGB (SAGB) phase and either become progenitors of ONe White Dwarfs or eventually explode as electron-capture SN (EC-SN). We study the sensitivity of $M_{up}$ to the C-burning reaction rate and to the treatment of convective mixing. In particular, we show the effect of a recent determination of the $^{12}C+$ $^{12}C$ fusion rate, as well as t...

Halabi, Ghina M

2014-01-01T23:59:59.000Z

230

Neutrinos: Nature's Identity Thieves?  

ScienceCinema (OSTI)

The oscillation of neutrinos from one variety to another has long been suspected, but was confirmed only about 15 years ago. In order for these oscillations to occur, neutrinos must have a mass, no matter how slight. Since neutrinos have long been thought to be massless, in a very real way, this phenomena is a clear signal of physics beyond the known. In this video, Fermilab's Dr Don Lincoln explains how we know it occurs and hints at the rich experimental program at several international laboratories designed to understand this complex mystery.

Dr. Don Lincoln

2013-07-22T23:59:59.000Z

231

Neutrinos: Nature's Identity Thieves?  

SciTech Connect

The oscillation of neutrinos from one variety to another has long been suspected, but was confirmed only about 15 years ago. In order for these oscillations to occur, neutrinos must have a mass, no matter how slight. Since neutrinos have long been thought to be massless, in a very real way, this phenomena is a clear signal of physics beyond the known. In this video, Fermilab's Dr Don Lincoln explains how we know it occurs and hints at the rich experimental program at several international laboratories designed to understand this complex mystery.

Lincoln, Don

2013-07-11T23:59:59.000Z

232

Neutrinos: Nature's Identity Thieves?  

ScienceCinema (OSTI)

The oscillation of neutrinos from one variety to another has long been suspected, but was confirmed only about 15 years ago. In order for these oscillations to occur, neutrinos must have a mass, no matter how slight. Since neutrinos have long been thought to be massless, in a very real way, this phenomena is a clear signal of physics beyond the known. In this video, Fermilab's Dr Don Lincoln explains how we know it occurs and hints at the rich experimental program at several international laboratories designed to understand this complex mystery.

Lincoln, Don

2014-08-07T23:59:59.000Z

233

Neutrino mass measurements  

Science Journals Connector (OSTI)

...swimming-pool-type nuclear reactors). This light is detected...side- branch in the nuclear reactions that power...which led to the next generation of experiments: Super-Kamiokande...are a large number of nuclear power reactors that sit in di erent...

2003-01-01T23:59:59.000Z

234

Neutrino mass measurements  

Science Journals Connector (OSTI)

...counts at the right energy, which should...tion to the dark matter. In fact...Galaxy Redshift Survey (2dFGRS) (Elgar...Galaxy redshift surveys like the 2dFGRS...Sloan Digital Sky Survey (Doroshkevich...one-third cold dark matter and two-thirds dark energy), some groups...

2003-01-01T23:59:59.000Z

235

Neutrino Astronomy and Cosmic Rays Spectroscopy at Horizons  

E-Print Network (OSTI)

A new air-showering physics may rise in next years at horizon, offering at different angles and altitudes a fine tuned filtered Cosmic Rays astrophysics and an upward Neutrino induced air-showering astronomy. Most of this opportunity arises because of neutrino masses, their mixing and the consequent replenishment of rarest tau flavor during its flight in Space. Horizontal air atmosphere act as a filter for High energy Cosmic Rays (CR) and as a beam dump for Ultra High Energy (UHE) neutrinos and a powerfull amplifier for its tau decay in air by its wide showering areas. Earth sharp shadows plays the role of a huge detector volume for UHE neutrino and a noise-free screen for upcoming EeVs tau air-showers (as well PeVs anti-neutrino electron air interactions). Projects for Tau Airshowers are growing at the top of a mountains or at the edge of a cliff. ASHRA in Hawaii and CRNTN in Utah are tracking fluorescence lights, while other novel projects on Crown array detectors on mountains, on balloons and satellites are elaborated for Cherenkov lights. AUGER, facing the Ande edges, ARGO located within a deep valley are testing inclined showers; MILAGRO (and MILAGRITO) may be triggered by horizontal up-going muon bundles from the Earth edges; HIRES and AUGER UHECR detectors, linking twin array telescopes along their axis may test horizontal Cerenkov blazing photons. MAGIC (Hess, Veritas) and Shalon Telescopes may act already like a detector for few PeVs and Glashow resonance neutrino events; MAGIC pointing downward to terrestrial ground acts as a massive tens of km^3 detector, making it the most sensitive dedicated neutrino telescope. MAGIC facing the sea edges must reveal mirrored downward UHECR Air-showers Cherenkov flashes. Magic-crown systems may lead to tens km^3, neutrino detectors.

D. Fargion

2006-04-20T23:59:59.000Z

236

Neutrinos in the Electron  

E-Print Network (OSTI)

We will show that one half of the rest mass of the electron is equal to the sum of the rest masses of electron neutrinos and that the other half of the rest mass of the electron is given by the energy in the sum of electric oscillations. With this composition we can explain the rest mass, the electric charge, the spin and the magnetic moment of the electron.

E. L. Koschmieder

2006-09-26T23:59:59.000Z

237

Strong Upper Limits on Sterile Neutrino Warm Dark Matter  

SciTech Connect

Sterile neutrinos are attractive dark matter candidates. Their parameter space of mass and mixing angle has not yet been fully tested despite intensive efforts that exploit their gravitational clustering properties and radiative decays. We use the limits on gamma-ray line emission from the Galactic center region obtained with the SPI spectrometer on the INTEGRAL satellite to set new constraints, which improve on the earlier bounds on mixing by more than 2 orders of magnitude, and thus strongly restrict a wide and interesting range of models.

Yueksel, Hasan [Department of Physics, Ohio State University, Columbus, Ohio 43210 (United States); Center for Cosmology and Astro-Particle Physics, Ohio State University, Columbus, Ohio 43210 (United States); Beacom, John F. [Department of Physics, Ohio State University, Columbus, Ohio 43210 (United States); Center for Cosmology and Astro-Particle Physics, Ohio State University, Columbus, Ohio 43210 (United States); Department of Astronomy, Ohio State University, Columbus, Ohio 43210 (United States); Watson, Casey R. [Department of Physics and Astronomy, Millikin University, Decatur, Illinois 62522 (United States)

2008-09-19T23:59:59.000Z

238

E-Print Network 3.0 - atmospheric neutrino anomaly Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

Physics Group Collection: Physics 15 Vol. 30 (1999) ACTA PHYSICA POLONICA B No 11 PHENOMENOLOGY OF NEUTRINO MASSES Summary: ; Atmospheric neutrino anomaly: Interpreted as...

239

Detectors for Neutrino Physics at the First Muon Collider  

E-Print Network (OSTI)

We consider possible detector designs for short-baseline neutrino experiments using neutrino beams produced at the First Muon Collider complex. The high fluxes available at the muon collider make possible high statistics deep-inelastic scattering neutrino experiments with a low-mass target. A design of a low-energy neutrino oscillation experiment on the ``tabletop'' scale is also discussed.

Deborah A. Harris; Kevin S. McFarland

1998-04-20T23:59:59.000Z

240

Semileptonic lepton-number- and/or lepton-flavor-violating ? decays in Majorana neutrino models  

Science Journals Connector (OSTI)

Motivated by the recent investigation of neutrinoless ?-lepton decays by the CLEO Collaboration, we perform a systematic analysis of such decays in a possible new-physics scenario with heavy Dirac and/or Majorana neutrinos, including heavy-neutrino nondecoupling effects, finite quark masses, and quark as well as meson mixings. We find that the ? lepton decays into an electron or muon and a pseudoscalar or vector meson can have branching ratios close to the experimental sensitivity. Numerical estimates show that the predominant decay modes of this kind are ?-?e-?, ?-?e-?0, and ?-?e-?0, with branching ratios of the order of 10-6.

A. Ilakovac, B. A. Kniehl, and A. Pilaftsis

1995-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "neutrino mass mixing" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Report of the APS Neutrino Study Reactor Working Group  

SciTech Connect

The worldwide program to understand neutrino oscillations and determine the neutrino mixing parameters, CP violating effects, and mass hierarchy will require a broad combination of measurements. The group believes that a key element of this future neutrino program is a multi-detector neutrino experiment (with baselines of {approx} 200 m and {approx} 1.5 km) with a sensitivity of sin{sup 2} 2{theta}{sub 13} = 0.01. In addition to oscillation physics, the reactor experiment may provide interesting measurements of sin{sup 2} {theta}{sub W} at Q{sup 2} = 0, neutrino couplings, magnetic moments, and mixing with sterile neutrino states. {theta}{sub 13} is one of the twenty-six parameters of the standard model, the best model of electroweak interactions for energies below 100 GeV and, as such, is worthy of a precision measurement independent of other considerations. A reactor experiment of the proposed sensitivity will allow a measurement of {theta}{sub 13} with no ambiguities and significantly better precision than any other proposed experiment, or will set limits indicating the scale of future experiments required to make progress. Figure 1 shows a comparison of the sensitivity of reactor experiments of different scales with accelerator experiments for setting limits on sin{sup 2} 2{theta}{sub 13} if the mixing angle is very small, or for making a measurement of sin{sup 2} 2{theta}{sub 13} if the angle is observable. A reactor experiment with a 1% precision may also resolve the degeneracy in the {theta}{sub 23} parameter when combined with long-baseline accelerator experiments. In combination with long-baseline measurements, a reactor experiment may give early indications of CP violation and the mass hierarchy. The combination of the T2K and Nova long-baseline experiments will be able to make significant measurements of these effects if sin{sup 2} 2{theta}{sub 13} > 0.05 and with enhanced beam rates can improve their reach to the sin{sup 2} 2{theta}{sub 13} > 0.02 level. If {theta}{sub 13} turns out to be smaller than these values, one will need other strategies for getting to the physics. Thus, an unambiguous reactor measurement of {theta}{sub 13} is an important ingredient in planning the strategy for the future neutrino program.

Abouzaid, E.; Anderson, K.; Barenboim, G.; Berger, B.; Blucher, E.; Bolton, T.; Choubey, S.; Conrad, J.; Formaggio, J.; Freedman, S.; Finely, D.; Fisher, P.; Fujikawa, B.; Gai, M.; Goodman, M.; de Goueva, A.; Hadley, N.; Hahn, R.; Horton-Smith, G.; Kadel, R.; Kayser, B.; Heeger, K.; Klein, J.; Learned, J.; Lindner, M.; Link, J.; Luk, K.-B.; McKeown, R.; Mocioiu, I.; Mohapatra, R.; Naples, D.; Peng, J.; Petcov, S.; Pilcher, J.; Rapidis, P.; Reyna, D.; Shaevitz, M.; Shrock, R.; Stanton, N.; Stefanski, R.; Yamamoto, R.; Worcester, M.

2004-10-28T23:59:59.000Z

242

Neutrino Superbeams  

NLE Websites -- All DOE Office Websites (Extended Search)

Upgraded conventional neutrino beams: Neutrino superbeams Upgraded conventional neutrino beams: Neutrino superbeams The capabilities of greatly upgraded conventional neutrino beams and the comparison with neutrino factories is under study. This page collects together some useful working information-- and at the bottom you can find links to studies that have already been done! GROUP REPORT: Oscillation Measurements with Upgraded Conventional Neutrino Beams V. Barger et al., hep-ex/0103052 (FERMILAB-FN-703), Addendum to Report FN-692 to the Fermilab Directorate, March 5, 2001. MI upgrade limitations Conf-97-199, W. Chou NUMI low energy beam with L = 732 km uoscillation signals for point IA1 (LMA scenario) but with sin**2 2theta(13) = 0.01, from Steve Geer. NUMI medium energy beam with L = 2800 km oscillation signals for

243

Discovering Long Wavelength Neutrino Oscillations in the Distorted Neutrino Spectrum of Galactic Supernova Remnants  

E-Print Network (OSTI)

We investigate the muon neutrino event rate in km$^3$ neutrino telescopes due to a number of galactic supernova remnants expected on the basis of these objects' known $\\gamma$-ray signals. We evaluate the potential of these neutrino signals to exhibit evidence of the sub-dominant neutrino oscillations expected in various neutrino mixing schemes including pseudo-Dirac scenarios and the Exact Parity Model. With ten years' data, neutrino signals from Sgr A East should either discover or exclude neutrino oscillations governed by a $\\delta m^2$ parameter in the range $10^{-12}$ to $10^{-15}$ eV$^2$. Such a capability is not available to terrestrial or solar system neutrino experiments.

Roland M. Crocker; Fulvio Melia; Raymond R. Volkas

2001-06-06T23:59:59.000Z

244

Discovery of the two-neutrino double-beta decay of xenon-136 with EXO-200.  

E-Print Network (OSTI)

??Recent neutrino oscillation measurements provide definitive evidence for non-zero neutrino masses. Oscillation measurements, however, only measure mass differences, not the absolute mass scale. Neutrinoless double-beta (more)

Stanford University, Dept. of Physics

2011-01-01T23:59:59.000Z

245

Progress in the physics of massive neutrinos  

E-Print Network (OSTI)

The current status of the physics of massive neutrinos is reviewed with a forward-looking emphasis. The article begins with the general phenomenology of neutrino oscillations in vacuum and matter and documents the experimental evidence for oscillations of solar, reactor, atmospheric and accelerator neutrinos. Both active and sterile oscillation possibilities are considered. The impact of cosmology (BBN, CMB, leptogenesis) and astrophysics (supernovae, highest energy cosmic rays) on neutrino observables and vice versa, is evaluated. The predictions of grand unified, radiative and other models of neutrino mass are discussed. Ways of determining the unknown parameters of three-neutrino oscillations are assessed, taking into account eight-fold degeneracies in parameters that yield the same oscillation probabilities, as well as ways to determine the absolute neutrino mass scale (from beta-decay, neutrinoless double-beta decay, large scale structure and Z-bursts). Critical unknowns at present are the amplitude of \

V. Barger; D. Marfatia; K. Whisnant

2003-09-16T23:59:59.000Z

246

On the Electric Charge of the Neutrino  

E-Print Network (OSTI)

Exact expression is obtained for the differential cross section of elastic electroweak scattering of longitudinal polarized massive Dirac neutrinos with the electric charge and anomalous magnetic moment on a spinless nucleus. This formula contains all necessary information about the nature of the neutrino mass, charge and magnetic moment. Some of them state that between the mass of the neutrino its electric charge there exists an interconnection.

Rasulkhozha S. Sarafiddinov

2010-12-09T23:59:59.000Z

247

Theoretical power spectra of mixed modes in low mass red giant stars  

E-Print Network (OSTI)

CoRoT and Kepler observations of red giant stars revealed very rich spectra of non-radial solar-like oscillations. Of particular interest was the detection of mixed modes that exhibit significant amplitude, both in the core and at the surface of the stars. It opens the possibility of probing the internal structure from their inner-most layers up to their surface along their evolution on the red giant branch as well as on the red-clump. Our objective is primarily to provide physical insight into the physical mechanism responsible for mixed-modes amplitudes and lifetimes. Subsequently, we aim at understanding the evolution and structure of red giants spectra along with their evolution. The study of energetic aspects of these oscillations is also of great importance to predict the mode parameters in the power spectrum. Non-adiabatic computations, including a time-dependent treatment of convection, are performed and provide the lifetimes of radial and non-radial mixed modes. We then combine these mode lifetimes a...

Grosjean, M; Belkacem, K; Montalban, J; Samadi, R; Mosser, B

2014-01-01T23:59:59.000Z

248

Ansatz of Leptonic Mixing: The Alliance of Bi-Maximal Mixing with a Single-Angle Rotation  

E-Print Network (OSTI)

We introduce an ansatz of the PMNS matrix that consists of specific types of transformations. Bi-maximal mixing is taken for the neutrino masses, while a single-angle rotation in the 1-2 block is taken for the charged lepton masses. Motivated by the implications of the recent results on neutrino oscillations, $\\theta_{23}$ in the first octant and non-zero $\\theta_{13}$ are predicted by the ansatz. Three physical mixing angles are expressed in terms of a single variable, the 1-2 angle of charged leptons, so that a simple relation among the angles has been obtained: $\\tan\\theta_{13}=\\sqrt{2}(\\sin\\theta_{23}-\\sin\\theta_{12})$. It follows that a model of the inverted hierarchy that can produce the given ansatz is proposed.

Kim Siyeon

2012-08-13T23:59:59.000Z

249

Ansatz of Leptonic Mixing: The Alliance of Bi-Maximal Mixing with a Single-Angle Rotation  

E-Print Network (OSTI)

We introduce an ansatz of the PMNS matrix that consists of specific types of transformations. Bi-maximal mixing is taken for the neutrino masses, while a single-angle rotation in the 1-2 block is taken for the charged lepton masses. Motivated by the implications of the recent results on neutrino oscillations, $\\theta_{23}$ in the first octant and non-zero $\\theta_{13}$ are predicted by the ansatz. Three physical mixing angles are expressed in terms of a single variable, the 1-2 angle of charged leptons, so that a simple relation among the angles has been obtained: $\\tan\\theta_{13}=\\sqrt{2}(\\sin\\theta_{23}-\\sin\\theta_{12})$. It follows that a model of the inverted hierarchy that can produce the given ansatz is proposed.

Siyeon, Kim

2012-01-01T23:59:59.000Z

250

La Thuile 2014: Theoretical premises to neutrino round table  

E-Print Network (OSTI)

This talk, dedicated to the memory of G. Giacomelli, introduced the round table on neutrinos held in February 2014. The topics selected for the discussion are: 1) the neutrinoless double beta decay rate (interpretation in terms of light neutrinos, nuclear uncertainties); 2) the physics in the gigantic water Cherenkov detectors (proton decay, atmospheric neutrinos); 3) the study of neutrino oscillations (mass hierarchy and CP violation; other neutrino states); 4) the neutrino astronomy at low and high energies (solar, supernova, cosmic neutrinos). The importance of an active interplay between theory and experiment is highlighted.

Francesco Vissani

2014-05-25T23:59:59.000Z

251

La Thuile 2014: Theoretical premises to neutrino round table  

E-Print Network (OSTI)

This talk, dedicated to the memory of G. Giacomelli, introduced the round table on neutrinos held in February 2014. The topics selected for the discussion are: 1) the neutrinoless double beta decay rate (interpretation in terms of light neutrinos, nuclear uncertainties); 2) the physics in the gigantic water Cherenkov detectors (proton decay, atmospheric neutrinos); 3) the study of neutrino oscillations (mass hierarchy and CP violation; other neutrino states); 4) the neutrino astronomy at low and high energies (solar, supernova, cosmic neutrinos). The importance of an active interplay between theory and experiment is highlighted.

Vissani, Francesco

2014-01-01T23:59:59.000Z

252

Solar Neutrinos  

DOE R&D Accomplishments (OSTI)

The prospect of studying the solar energy generation process directly by observing the solar neutrino radiation has been discussed for many years. The main difficulty with this approach is that the sun emits predominantly low energy neutrinos, and detectors for observing low fluxes of low energy neutrinos have not been developed. However, experimental techniques have been developed for observing neutrinos, and one can foresee that in the near future these techniques will be improved sufficiently in sensitivity to observe solar neutrinos. At the present several experiments are being designed and hopefully will be operating in the next year or so. We will discuss an experiment based upon a neutrino capture reaction that is the inverse of the electron-capture radioactive decay of argon-37. The method depends upon exposing a large volume of a chlorine compound, removing the radioactive argon-37 and observing the characteristic decay in a small low-level counter.

Davis, R. Jr.; Harmer, D. S.

1964-12-00T23:59:59.000Z

253

Measuring CP violation and mass ordering in joint long baseline experiments with superbeams  

Science Journals Connector (OSTI)

We propose to measure the CP phase ?CP, the magnitude of the neutrino mixing matrix element |Ue3| and the sign of the atmospheric scale mass-squared difference ?m312 with a superbeam by the joint analysis of two different long baseline neutrino oscillation experiments. One is a long baseline experiment (LBL) at 300 km and the other is a very long baseline (VLBL) experiment at 2100 km. We take the neutrino source to be the approved high intensity proton synchrotron, HIPA. The neutrino beam for the LBL is the 2-degree off-axis superbeam, and for the VLBL a narrowband superbeam. Taking into account all possible errors, we evaluate the event rates required and the sensitivities that can be attained for the determination of ?CP and the sign of ?m312. We arrive at a representative scenario for a reasonably precise probe of this part of neutrino physics.

K. Whisnant; Jin Min Yang; Bing-Lin Young

2003-01-21T23:59:59.000Z

254

Masses of Fundamental Particles  

E-Print Network (OSTI)

In the original paper entitled, "Masses of Fundamental Particles"(arXiv:1109.3705v5, 10 Feb 2012), not only the masses of fundamental particles including the weak bosons, Higgs boson, quarks, and leptons, but also the mixing angles of quarks and those of neutrinos are all explained and/or predicted in the unified composite models of quarks and leptons successfully. In this addendum entitled, "Higgs Boson Mass in the Minimal Unified Subquark Model", it is emphasized that the Higgs boson mass is predicted to be about 130Gev in the minimal unified subquark model, which agrees well with the experimental values of 125-126GeV recently found by the ATLAS and CMS Collaborations at the LHC.

Hidezumi Terazawa

2014-06-11T23:59:59.000Z

255

How opaque is the Earth to ultrahigh energy neutrinos?  

Science Journals Connector (OSTI)

We carry out a numerical calculation of ultrahigh energy neutrino propagation through the Earth, taking into account the neutrino regeneration process in both neutral current and charged current neutrino interactions. The attenuation of neutrinos traversing the Earth (shadow effect) is determined, and the fluxes of ?-induced upward-going leptons (muon and tau) are obtained at the Earths surface and for two configurations of the neutrino flavor in the incident neutrino flux (????? mixing). The implications of these results are discussed in the context of the possibility of detection of ?-induced leptons in the next round of fluorescent telescopes such as the AUGER detector.

C. E. Navia; C. R. A. Augusto; H. M. Portella; H. Shigueoka

2003-05-23T23:59:59.000Z

256

Combining CPT-conjugate Neutrino channels at Fermilab  

E-Print Network (OSTI)

We explore an alternative strategy to determine the neutrino mass hierarchy by making use of possible future neutrino facilities at Fermilab. Here, we use CPT-conjugate neutrino channels, exploiting a nu_mu beam from the NuMI beamline and a barnu_e beam from a betabeam experimental setup. Both experiments are performed at approximately the same E/L. We present different possible accelerator scenarios for the betabeam neutrino setup and fluxes. This CPT-conjugate neutrino channel scenario can extract the neutrino mass hierarchy down to sin^2 (2 theta_13) \\approx 0.02.

Andreas Jansson; Olga Mena; Stephen Parke; Niki Saoulidou

2007-11-07T23:59:59.000Z

257

Booster Neutrino Experiment - About Neutrinos  

NLE Websites -- All DOE Office Websites (Extended Search)

Adventure An interactive tour of quarks, neutrinos, anti-matter, extra dimensions, dark matter, accelerators, and particle detectors. Developed by the Particle Data Group....

258

Strong thermal Leptogenesis: an exploded view of the low energy neutrino parameters in the SO(10)-inspired model  

E-Print Network (OSTI)

Leptogenesis is an attractive scenario in which neutrino masses and baryon asymmetry of the Universe are explained together under a minimal set of assumptions. After formulating the problem of initial conditions and introducing the strong thermal leptogenesis conditions as solution, we show that, within the framework provided by the \\soten~model of leptogenesis, the latter lead to a set of testable predictions on the same neutrino parameters currently under experimental investigations. The emerging scenario selects the normal ordering of the neutrino mass pattern, a large value for the reactor mixing angle, $2\\deg \\lesssim \\theta_{13} \\lesssim 20\\deg$, as well as a non maximal atmospheric mixing angle, $16\\deg \\lesssim \\theta_{23} \\lesssim 41\\deg$, and favours negative values for the Dirac phase \\delta. The signature of the proposed strong thermal \\soten~solutions is in the relation obtained between the effective Majorana mass and the lightest neutrino mass: $m_{ee} \\approx 0.8 \\, m_1 \\approx 15 $ meV.

Marzola, Luca

2014-01-01T23:59:59.000Z

259

Effects of CP Violation from Neutral Heavy Fermions on Neutrino Oscillations, and the LSND/MiniBooNE Anomalies  

E-Print Network (OSTI)

Neutrinos may mix with ultralight fermions, which gives flavor oscillations, and with heavier fermions, which yields short distance flavor change. I consider the case where both effects are present. I show that in the limit where a single oscillation length is experimentally accessible, the effects of heavier fermions on neutrino oscillations can generically be accounted for by a simple formula containing four parameters, including observable CP violation. I consider the anomalous LSND and MiniBooNE results, and show that these can be fit in a model with CP violation and two additional sterile neutrinos, one in the mass range between 0.1 and 20 eV, and the other with mass between 33 eV and 40 GeV. I also show that this model can avoid conflict with constraints from existing null short baseline experimental results.

Ann E Nelson

2010-10-19T23:59:59.000Z

260

Daya Bay Reactor Neutrino Project at NERSC  

NLE Websites -- All DOE Office Websites (Extended Search)

Daya Bay Reactor Neutrino Daya Bay Reactor Neutrino Experiment Daya Bay Reactor Neutrino Experiment Daya Bay is an international neutrino-oscillation experiment designed to determine the last unknown neutrino mixing angle θ13 using anti-neutrinos produced by the Daya Bay and Ling Ao Nuclear Power Plant reactors. The experiment is being built by blasting three kilometers of tunnel through the granite rock under the mountains where the power plants are located. Data collection is now scheduled to start in in 2011. On the PDSF cluster at NERSC, Daya Bay performs simulations of the detectors, reactors, and surrounding mountains to help design and anticipate detector properties and behavior. Once real data are available, Daya Bay will be using NERSC to analyze data and NERSC HPSS will be the central U.S. repository for all raw

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261

Dynamical Collective Calculation of Supernova Neutrino Signals  

SciTech Connect

We present the first calculations with three flavors of collective and shock wave effects for neutrino propagation in core-collapse supernovae using hydrodynamical density profiles and the S matrix formalism. We explore the interplay between the neutrino-neutrino interaction and the effects of multiple resonances upon the time signal of positrons in supernova observatories. A specific signature is found for the inverted hierarchy and a large third neutrino mixing angle and we predict, in this case, a dearth of lower energy positrons in Cherenkov detectors midway through the neutrino signal and the simultaneous revelation of valuable information about the original fluxes. We show that this feature is also observable with current generation neutrino detectors at the level of several sigmas.

Gava, Jerome; Kneller, James; Volpe, Cristina; McLaughlin, G. C. [Institut de Physique Nucleaire, F-91406 Orsay cedex, CNRS/IN2P3 and University of Paris-XI (France); Department of Physics, North Carolina State University, Raleigh, North Carolina 27695-8202 (United States)

2009-08-14T23:59:59.000Z

262

Pion condensation in a dense neutrino gas  

E-Print Network (OSTI)

We argue that using an equilibrated gas of neutrinos it is possible to probe the phase diagram of QCD for finite isospin and small baryon chemical potentials. We discuss this region of the phase diagram in detail and demonstrate that for large enough neutrino densities a Bose-Einstein condensate of positively charged pions arises. Moreover, we show that for nonzero neutrino density the degeneracy in the lifetimes and masses of the charged pions is lifted.

Hiroaki Abuki; Tomas Brauner; Harmen J. Warringa

2009-08-26T23:59:59.000Z

263

Heavy sterile neutrinos, entropy and relativistic energy production, and the relic neutrino background  

E-Print Network (OSTI)

We explore the implications of the existence of heavy neutral fermions (i.e., sterile neutrinos) for the thermal history of the early universe. In particular, we consider sterile neutrinos with rest masses in the 100 MeV to 500 MeV range, with couplings to ordinary active neutrinos large enough to guarantee thermal and chemical equilibrium at epochs in the early universe with temperatures T > 1 GeV, but in a range to give decay lifetimes from seconds to minutes. Such neutrinos would decouple early, with relic densities comparable to those of photons, but decay out of equilibrium, with consequent prodigious entropy generation prior to, or during, Big Bang Nucleosynthesis (BBN). Most of the ranges of sterile neutrino rest mass and lifetime considered are at odds with Cosmic Microwave Background (CMB) limits on the relativistic particle contribution to energy density (e.g., as parameterized by N_eff). However, some sterile neutrino parameters can lead to an acceptable N_eff. These parameter ranges are accompanied by considerable dilution of the ordinary background relic neutrinos, possibly an adverse effect on BBN, but sometimes fall in a range which can explain measured neutrino masses in some particle physics models. A robust signature of these sterile neutrinos would be a measured N_eff not equal to 3 coupled with no cosmological signal for neutrino rest mass when the detection thresholds for these probes are below laboratory-established neutrino mass values, either as established by the atmospheric neutrino oscillation scale or direct measurements with, e.g., KATRIN or neutrino-less double beta decay experiments.

George M. Fuller; Chad T. Kishimoto; Alexander Kusenko

2011-10-28T23:59:59.000Z

264

Measures on Mixing Angles  

E-Print Network (OSTI)

We address the problem of the apparently very small magnitude of CP violation in the standard model, measured by the Jarlskog invariant J. In order to make statements about probabilities for certain values of J, we seek to find a natural measure on the space of Kobayashi-Maskawa matrices, the double quotient U(1)^2\\SU(3)/U(1)^2. We review several possible, geometrically motivated choices of the measure, and compute expectation values for powers of J for these measures. We find that different choices of the measure generically make the observed magnitude of CP violation appear finely tuned. Since the quark masses and the mixing angles are determined by the same set of Yukawa couplings, we then do a second calculation in which we take the known quark mass hierarchy into account. We construct the simplest measure on the space of 3 x 3 Hermitian matrices which reproduces this known hierarchy. Calculating expectation values for powers of J in this second approach, we find that values of J close to the observed value are now rather likely, and there does not seem to be any fine tuning. Our results suggest that the choice of Kobayashi-Maskawa angles is closely linked to the observed mass hierarchy. We close by discussing the corresponding case of neutrinos.

Gary W. Gibbons; Steffen Gielen; C. N. Pope; Neil Turok

2008-10-27T23:59:59.000Z

265

Neutrino Burst from Supernovae and Neutrino Oscillation  

Science Journals Connector (OSTI)

......solar, atmospheric, reactor neutrinos and so on...anti-neutrinos from nuclear reactors, spal- lation products...atmospheric, and reactor neutrinos. (Since...is expected that next generation of water Cherenkov detectors......

Katsuhiko Sato; Keitaro Takahashi; Shin'ichiro Ando

2002-03-01T23:59:59.000Z

266

CP and T violation tests in neutrino oscillation  

Science Journals Connector (OSTI)

We examine how large violation effects of CP and T are allowed in long baseline neutrino experiments. When we attribute only the atmospheric neutrino anomaly to neutrino oscillation we may have large CP-violation effects. When we attribute both the atmospheric neutrino anomaly and the solar neutrino deficit to neutrino oscillation we may have sizable T violation effects proportional to the ratio of the two mass differences; it is difficult to see CP violation since we cannot ignore the matter effect. We give a simple expression for T violation in the presence of matter.

Jiro Arafune and Joe Sato

1997-02-01T23:59:59.000Z

267

Analytical Theory of Neutrino Oscillations in Matter with CP violation  

E-Print Network (OSTI)

We develop an exact analytical formulation of neutrino oscillations in matter within the framework of the Standard Neutrino Model assuming 3 Dirac Neutrinos. Our Hamiltonian formulation, which includes CP violation, leads to expressions for the partial oscillation probabilities that are linear combinations of spherical Bessel functions in the eigenvalue differences. The coefficients of these Bessel functions are polynomials in the neutrino CKM matrix elements, the neutrino mass differences squared, the strength of the neutrino interaction with matter, and the neutrino mass eigenvalues in matter. We give exact closed-form expressions for all partial oscillation probabilities in terms of these basic quantities. Adopting the Standard Neutrino Model, we then examine how the exact expressions for the partial oscillation probabilities might simplify by expanding in one of the small parameters {\\alpha} and sin{\\theta}13 of this model. We show explicitly that for small {\\alpha} and sin{\\theta}13 there are branch poin...

Johnson, Mikkel B; Kisslinger, Leonard S

2015-01-01T23:59:59.000Z

268

Neutrinos at high energy accelerators  

E-Print Network (OSTI)

PREAMBLE, BRIEF HISTORY AND PRELIMINARIES, QUICK REVIEW OF BASIC NEUTRINO PROPERTIES, CHARGED CURRENT NEUTRINO PROCESSES, NEUTRAL CURRENT NEUTRINO PROCESSES, VERY HEAVY NEUTRINOS, CONCLUDING SUMMARY

Probir Roy

1993-08-02T23:59:59.000Z

269

Confusing the extragalactic neutrino flux limit with a neutrino propagation limit  

SciTech Connect

We study the possible suppression of the extragalactic neutrino flux due to a nonstandard interaction during its propagation. In particular, we study neutrino interaction with an ultra-light scalar field dark matter. It is shown that the extragalactic neutrino flux may be suppressed by such an interaction, leading to a new mechanism to reduce the ultra-high energy neutrino flux. We study both the cases of non-self-conjugate as well as self-conjugate dark matter. In the first case, the suppression is independent of the neutrino and dark matter masses. We conclude that care must be taken when explaining limits on the neutrino flux through source acceleration mechanisms only, since there could be other mechanisms for the reduction of the neutrino flux.

Barranco, Juan [Instituto de Astronoma, Universidad Nacional Autonoma de Mxico, Mexico, DF 04510 (Mexico); Miranda, Omar G. [Departamento de Fsica, Centro de Investigacin y de Estudios Avanzados del IPN, Apdo. Postal 14-740 07000 Mxico, D.F. (Mexico); Moura, Celio A. [Centro de Cincias Naturais e Humanas, Universidade Federal do ABC, Rua Santa Adlia, 166, 09210-170 Santo Andr, SP (Brazil); Rashba, Timur I. [Max-Planck-Institute for Solar System Research, Katlenburg-Lindau, 37191 (Germany); Rossi-Torres, Fernando, E-mail: barranco@astroscu.unam.mx, E-mail: Omar.Miranda@fis.cinvestav.mx, E-mail: celio.moura@ufabc.edu.br, E-mail: timur@mppmu.mpg.de, E-mail: ftorres@ifi.unicamp.br [Instituto de Fsica Terica, Universidade Estadual Paulista, Rua Dr. Bento Teobaldo Ferraz, 271 - Bl. II, 01140-070, So Paulo, SP (Brazil)

2011-10-01T23:59:59.000Z

270

Neutrinoless Double Beta Decay with Composite Neutrinos.  

E-Print Network (OSTI)

We study in detail the contribution of heavy composite Majorana neutrinos to neutrino-less double beta decay (0???). Our analysis confirms the result of a previous estimate by two of the authors. Excited neutrinos couple to the electroweak gauge bosons through a magnetic type effective Lagrangian. The relevant nuclear matrix element is related to matrix elements available in the literature and current bounds on the half-life of 0??? are converted into bounds on the compositeness scale and/or the heavy neutrino mass. Our bounds are of the same order of magnitude as those available from accelerator experiments.

O. Panella (a; C. Carimalo (b; Y. N. Srivastava (a; A. Widom (c

1997-01-01T23:59:59.000Z

271

CPT-Odd Resonances in Neutrino Oscillations  

Science Journals Connector (OSTI)

We consider the consequences for future neutrino factory experiments of small CPT-odd interactions in neutrino oscillations. The ????? and ????? survival probabilities at a baseline L=732 km can test for CPT-odd contributions at orders of magnitude better sensitivity than present neutrino sector limits. Interference between the CPT-violating interaction and CPT-even mass terms in the Lagrangian can lead to a resonant enhancement of the oscillation amplitude. For oscillations in matter, a simultaneous enhancement of both neutrino and antineutrino oscillation amplitudes is possible.

V. Barger; S. Pakvasa; T. J. Weiler; K. Whisnant

2000-12-11T23:59:59.000Z

272

Solar Neutrinos: Status and Prospects  

E-Print Network (OSTI)

We describe the current status of solar neutrino measurements and of the theory -- both neutrino physics and solar astrophysics -- employed in interpreting measurements. Important recent developments include Super-Kamiokande's determination of the neutrino-electron elastic scattering rate for 8B neutrinos to 3%; the latest SNO global analysis in which the inclusion of low-energy data from SNO I and II significantly narrowed the range of allowed values for the neutrino mixing angle theta12; Borexino results for both the 7Be and pep neutrino fluxes, the first direct measurements constraining the rate of ppI and ppII burning in the Sun; global reanalyses of solar neutrino data that take into account new reactor results on theta13; a new decadal evaluation of the nuclear physics of the pp chain and CNO cycle defining best values and uncertainties in the nuclear microphysics input to solar models; recognition of an emerging discrepancy between two tests of solar metallicity, helioseismological mappings of the sound speed in the solar interior, and analyses of the metal photoabsorption lines based on our best current description of the Sun's photosphere; a new round of standard solar model calculations optimized to agree either with helioseismology or with the new photospheric analysis; and, motivated by the solar abundance problem, the development of nonstandard, accreting solar models, in order to investigate possible consequences of the metal segregation that occurred in the proto-solar disk. We review this progress and describe how new experiments such as SNO+ could help us further exploit neutrinos as a unique probe of stellar interiors.

W. C. Haxton; R. G. Hamish Robertson; Aldo M. Serenelli

2012-08-28T23:59:59.000Z

273

SAGE: Solar Neutrino Data from SAGE, the Russian-American Gallium Solar Neutrino Experiment  

DOE Data Explorer (OSTI)

SAGE is a solar neutrino experiment based on the reaction 71Ga + n goes to 71Ge + e-. The 71Ge atoms are chemically extracted from a 50-metric ton target of Ga metal and concentrated in a sample of germane gas mixed with xenon. The atoms are then individually counted by observing their decay back to 71Ga in a small proportional counter. The distinguishing feature of the experiment is its ability to detect the low-energy neutrinos from proton-proton fusion. These neutrinos, which are made in the primary reaction that provides the Sun's energy, are the major component of the solar neutrino flux and have not been observed in any other way. To shield the experiment from cosmic rays, it is located deep underground in a specially built facility at the Baksan Neutrino Observatory in the northern Caucasus mountains of Russia. Nearly 100 measurements of the solar neutrino flux have been made during 1990-2000, and their combined result is a neutrino capture rate that is well below the prediction of the Standard Solar Model. The significant suppression of the solar neutrino flux that SAGE and other solar neutrino experiments have observed gives a strong indication for the existence of neutrino oscillations. [copied from the SAGE homepage at http://ewi.npl.washington.edu/SAGE/SAGE.html

SAGE Collaboration

274

Solar Neutrinos  

E-Print Network (OSTI)

Experimental work with solar neutrinos has illuminated the properties of neutrinos and tested models of how the sun produces its energy. Three experiments continue to take data, and at least seven are in various stages of planning or construction. In this review, the current experimental status is summarized, and future directions explored with a focus on the effects of a non-zero theta-13 and the interesting possibility of directly testing the luminosity constraint. Such a confrontation at the few-percent level would provide a prediction of the solar irradiance tens of thousands of years in the future for comparison with the present-day irradiance. A model-independent analysis of existing low-energy data shows good agreement between the neutrino and electromagnetic luminosities at the +/- 20 % level.

R. G. H. Robertson

2006-02-05T23:59:59.000Z

275

Propagation of Neutrinos through Magnetized Gamma-Ray Burst Fireball  

E-Print Network (OSTI)

The neutrino self-energy is calculated in a weakly magnetized plasma consists of electrons, protons, neutrons and their anti-particles and using this we have calculated the neutrino effective potential up to order $M^{-4}_W$. In the absence of magnetic field it reduces to the known result. We have also calculated explicitly the effective potentials for different backgrounds which may be helpful in different environments. By considering the mixing of three active neutrinos in the medium with the magnetic field we have derived the survival and conversion probabilities of neutrinos from one flavor to another and also the resonance condition is derived. As an application of the above, we considered the dense and relativistic plasma of the Gamma-Ray Bursts fireball through which neutrinos of 5-30 MeV can propagate and depending on the fireball parameters they may oscillate resonantly or non-resonantly from one flavor to another. These MeV neutrinos are produced due to stellar collapse or merger events which trigger the Gamma-Ray Burst. The fireball itself also produces MeV neutrinos due to electron positron annihilation, inverse beta decay and nucleonic bremsstrahlung. Using the three neutrino mixing and considering the best fit values of the neutrino parameters, we found that electron neutrinos are hard to oscillate to another flavors. On the other hand, the muon neutrinos and the tau neutrinos oscillate with equal probability to one another, which depends on the neutrino energy, temperature and size of the fireball. Comparison of oscillation probabilities with and without magnetic field shows that, they depend on the neutrino energy and also on the size of the fireball. By using the resonance condition, we have also estimated the resonance length of the propagating neutrinos as well as the baryon content of the fireball.

Sarira Sahu; Nissim Fraija; Yong-Yeon Keum

2009-11-10T23:59:59.000Z

276

Pseudo Dirac neutrinos in the seesaw model  

Science Journals Connector (OSTI)

A specific class of textures for the Dirac and Majorana mass matrices in the seesaw model leading to a pair of almost degenerate neutrinos is discussed. These textures can be obtained by imposing a horizontal U(1) symmetry. A specific model is discussed in which (1) all three neutrino masses are similar in magnitude and could lie around 1 eV providing the hot component of the dark matter in the Universe, (2) two of these are highly degenerate and their (mass)2 difference could solve the solar neutrino problem through the large angle MSW solution, and (3) the electron neutrino mass may be observable through a Kurie plot as well as through a search of the neutrinoless double ? decay.

Gautam Dutta and Anjan S. Joshipura

1995-04-01T23:59:59.000Z

277

Nuclear deformation and neutrinoless double-? decay of Zr94,96, Mo98,100, Ru104, Pd110, Te128,130, and Nd150 nuclei within a mechanism involving neutrino mass  

Science Journals Connector (OSTI)

The (?-?-)0? decay of Zr94,96, Mo98,100, Ru104, Pd110, Te128,130, and Nd150 isotopes for the 0+?0+ transition is studied in the projected Hartree-Fock-Bogoliubov framework. In our earlier work, the reliability of HFB intrinsic wave functions participating in the ?-?- decay of the above-mentioned nuclei has been established by obtaining an overall agreement between the theoretically calculated spectroscopic properties, namely yrast spectra, reduced B(E2:0+?2+) transition probabilities, quadrupole moments Q(2+), gyromagnetic factors g(2+) as well as half-lives T1/22? for the 0+?0+ transition and the available experimental data. In the present work, we study the (?-?-)0? decay for the 0+?0+ transition in a mechanism involving neutrino mass and extract limits on effective mass of light as well as heavy neutrinos from the observed half-lives T1/20?(0+?0+) using nuclear transition matrix elements calculated with the same set of wave functions. Further, the effect of deformation on the nuclear transition matrix elements required to study the (?-?-)0? decay in such a mass mechanism is investigated. It is noticed that the deformation effect on nuclear transition matrix elements is of approximately the same magnitude in (?-?-)2? and (?-?-)0? decay.

K. Chaturvedi, R. Chandra, P. K. Rath, P. K. Raina, and J. G. Hirsch

2008-11-04T23:59:59.000Z

278

The accretion of solar material onto white dwarfs: No mixing with core material implies that the mass of the white dwarf is increasing  

SciTech Connect

Cataclysmic Variables (CVs) are close binary star systems with one component a white dwarf (WD) and the other a larger cooler star that fills its Roche Lobe. The cooler star is losing mass through the inner Lagrangian point of the binary and some unknown fraction of this material is accreted by the WD. One consequence of the WDs accreting material, is the possibility that they are growing in mass and will eventually reach the Chandrasekhar Limit. This evolution could result in a Supernova Ia (SN Ia) explosion and is designated the Single Degenerate Progenitor (SD) scenario. This paper is concerned with the SD scenario for SN Ia progenitors. One problem with the single degenerate scenario is that it is generally assumed that the accreting material mixes with WD core material at some time during the accretion phase of evolution and, since the typical WD has a carbon-oxygen CO core, the mixing results in large amounts of carbon and oxygen being brought up into the accreted layers. The presence of enriched carbon causes enhanced nuclear fusion and a Classical Nova explosion. Both observations and theoretical studies of these explosions imply that more mass is ejected than is accreted. Thus, the WD in a Classical Nova system is losing mass and cannot be a SN Ia progenitor. However, the composition in the nuclear burning region is important and, in new calculations reported here, the consequences to the WD of no mixing of accreted material with core material have been investigated so that the material involved in the explosion has only a Solar composition. WDs with a large range in initial masses and mass accretion rates have been evolved. I find that once sufficient material has been accreted, nuclear burning occurs in all evolutionary sequences and continues until a thermonuclear runaway (TNR) occurs and the WD either ejects a small amount of material or its radius grows to about 10{sup 12} cm and the evolution is ended. In all cases where mass ejection occurs, the mass of the ejecta is far less than the mass of the accreted material. Therefore, all the WDs are growing in mass. It is also found that the accretion time to explosion can be sufficiently short for a 1.0M{sub ?} WD that recurrent novae can occur on a low mass WD. This mass is lower than typically assumed for the WDs in recurrent nova systems. Finally, the predicted surface temperatures when the WD is near the peak of the explosion imply that only the most massive WDs will be significant X-ray emitters at this time.

Starrfield, Sumner, E-mail: starrfield@asu.edu [School of Earth and Space Exploration, Arizona State University, P. O. Box 871404, Tempe, AZ 85287-1404 (United States)] [School of Earth and Space Exploration, Arizona State University, P. O. Box 871404, Tempe, AZ 85287-1404 (United States)

2014-04-15T23:59:59.000Z

279

Masatoshi Koshiba and Cosmic Neutrinos  

Office of Scientific and Technical Information (OSTI)

Masatoshi Koshiba and Cosmic Neutrinos Masatoshi Koshiba and Cosmic Neutrinos Resources with Additional Information Masatoshi Koshiba Courtesy of Sebastian Brandt 'The 2002 Nobel Prize in Physics has been awarded to ... Masatoshi Koshiba of the International Center for Elementary Particle Physics at the University of Tokyo in Japan, ... "for pioneering contributions to astrophysics, in particular for the detection of cosmic neutrinos." ... Neutrinos are important in astrophysics since they might have played a considerable role in shaping early galaxies; they are the form of energy coming directly from the solar core; and they account for the largest share of energy released during supernova explosions....'1 ...Koshiba, professor emeritus at the University of Tokyo, received his doctorate from the University of Rochester in [1955]. This year [2000], he is the co-recipient of the Wolf Prize in Physics, considered second only to the Nobel Prize in prestige, for his discovery that neutrinos have mass. Neutrinos are tiny particles smaller than atoms, and Koshiba's discovery is being hailed for its ramifications in the study of astronomical objects and the fundamental properties of matter, helping scientists to understand the birth of the universe. Koshiba started his career as a research associate at the University of Rochester, then went on to teach at the University of Tokyo." 2

280

Neutrino oscillations  

Science Journals Connector (OSTI)

...Solar neutrino oscillations The thermonuclear fusion reactions in the core of the Sun...dominant source of solar energy is the fusion process 4p !4 He + 2n e + 2e...related to the 4p ! 4He+2n e +2e+ fusion rate. Consequently, the theoretical...

2002-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "neutrino mass mixing" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Electromagnetic properties of neutrinos  

E-Print Network (OSTI)

A short review on electromagnetic properties of neutrinos is presented. In spite of many efforts in the theoretical and experimental studies of neutrino electromagnetic properties, they still remain one of the main puzzles related to neutrinos.

Carlo Giunti; Alexander Studenikin

2010-06-08T23:59:59.000Z

282

Status of three-neutrino oscillation parameters, circa 2013  

E-Print Network (OSTI)

The standard three-neutrino (3nu) oscillation framework is being increasingly refined by results coming from different sets of experiments, using neutrinos from solar, atmospheric, accelerator and reactor sources. At present, each of the known oscillation parameters [the two squared mass gaps (delta m^2, Delta m^2) and the three mixing angles (theta_12}, theta_13, theta_23)] is dominantly determined by a single class of experiments. Conversely, the unknown parameters [the mass hierarchy, the theta_23 octant and the CP-violating phase delta] can be currently constrained only through a combined analysis of various (eventually all) classes of experiments. In the light of recent new results coming from reactor and accelerator experiments, and of their interplay with solar and atmospheric data, we update the estimated N-sigma ranges of the known 3nu parameters, and revisit the status of the unknown ones. Concerning the hierarchy, no significant difference emerges between normal and inverted mass ordering. A slight overall preference is found for theta_23 in the first octant and for nonzero CP violation with sin delta < 0; however, for both parameters, such preference exceeds 1 sigma only for normal hierarchy. We also discuss the correlations and stability of the oscillation parameters within different combinations of data sets.

F. Capozzi; G. L. Fogli; E. Lisi; A. Marrone; D. Montanino; A. Palazzo

2014-05-05T23:59:59.000Z

283

Earth Matter Effects in Detection of Supernova Neutrinos  

E-Print Network (OSTI)

We calculated the matter effect, including both the Earth and supernova, on the detection of neutrinos from type II supernovae at the proposed Daya Bay reactor neutrino experiment. It is found that apart from the dependence on the flip probability P_H inside the supernova and the mass hierarchy of neutrinos, the amount of the Earth matter effect depends on the direction of the incoming supernova neutrinos, and reaches the biggest value when the incident angle of neutrinos is around 93^\\circ. In the reaction channel \\bar{\

X. -H. Guo; Bing-Lin Young

2006-05-11T23:59:59.000Z

284

Recent Results from Long-Baseline Neutrino Experiments  

E-Print Network (OSTI)

We are moving into an era of precision measurements of neutrino mixing, and it is increasingly necessary to use a 3-flavor framework to describe the results. This paper will focus on recent results from long-baseline neutrino experiments, especially accelerator-based beams. Using $\

Alysia D. Marino

2014-11-12T23:59:59.000Z

285

Is Cosmology Compatible with Sterile Neutrinos?  

SciTech Connect

By combining data from cosmic microwave background experiments (including the recent WMAP third year results), large scale structure, and Lyman-{alpha} forest observations, we constrain the hypothesis of a fourth, sterile, massive neutrino. For the 3 massless+1 massive neutrino case, we bound the mass of the sterile neutrino to m{sub s}<0.26 eV (0.44 eV) at 95% (99.9%) C.L., which excludes at high significance the sterile neutrino hypothesis as an explanation of the LSND anomaly. We generalize the analysis to account for active neutrino masses and the possibility that the sterile abundance is not thermal. In the latter case, the contraints in the (mass,density) plane are nontrivial. For a mass of >1 or <0.05 eV, the cosmological energy density in sterile neutrinos is always constrained to be {omega}{sub {nu}}<0.003 at 95% C.L., but for a mass of {approx}0.25 eV, {omega}{sub {nu}} can be as large as 0.01.

Dodelson, Scott; Melchiorri, Alessandro; Slosar, Anze [Particle Astrophysics Center, FERMILAB, Batavia, Illinois 60510-0500 (United States); Physics Department and Sezione INFN, University of Rome 'La Sapienza', Ple Aldo Moro 2, 00185 Rome (Italy); Faculty of Mathematics and Physics, University of Ljubljana, 1000 Ljubljana (Slovenia)

2006-07-28T23:59:59.000Z

286

On Symmetric Lepton Mixing Matrices  

E-Print Network (OSTI)

Contrary to the quark mixing matrix, the lepton mixing matrix could be symmetric. We study the phenomenological consequences of this possibility. In particular, we find that symmetry would imply that |U_{e3}| is larger than 0.16, i.e., above its current 2 sigma limit. The other mixing angles are also constrained and CP violating effects in neutrino oscillations are suppressed, even though |U_{e3}| is sizable. Maximal atmospheric mixing is only allowed if the other observables are outside their current 3 sigma ranges, and sin^2 theta_{23} lies typically below 0.5. The Majorana phases are not affected, but the implied values of the solar neutrino mixing angle have some effect on the predictions for neutrinoless double beta decay. We further discuss some formal properties of a symmetric mixing matrix.

Hochmuth, K A; Hochmuth, Kathrin A.; Rodejohann, Werner

2007-01-01T23:59:59.000Z

287

Neutrino Spectroscopy with Atoms and Molecules  

E-Print Network (OSTI)

We give a comprehensive account of our proposed experimental method of using atoms or molecules in order to measure parameters of neutrinos still undetermined; the absolute mass scale, the mass hierarchy pattern (normal or inverted), the neutrino mass type (Majorana or Dirac), and the CP violating phases including Majorana phases. There are advantages of atomic targets, due to the closeness of available atomic energies to anticipated neutrino masses, over nuclear target experiments. Disadvantage of using atomic targets, the smallness of rates, is overcome by the macro-coherent amplification mechanism. The atomic or molecular process we use is a cooperative deexcitation of a collective body of atoms in a metastable level |e> emitting a neutrino pair and a photon; |e> -> |g> + gamma + nu_i nu_j where nu_i's are neutrino mass eigenstates. The macro-coherence is developed by trigger laser irradiation. We discuss aspects of the macro-coherence development by setting up the master equation for the target quantum state and propagating electric field. With a choice of heavy target atom or molecule such as Xe or I_2 that has a large M1 x E1 matrix element between |e> and |g>, we show that one can determine three neutrino masses along with the mass hierarchy pattern by measuring the photon spectral shape. If one uses a target of available energy of a fraction of 1 eV, Majorana CP phases may be determined. Our master equation, when applied to E1 x E1 transition such as pH_2 vibrational transition Xv=1 -> 0, can describe explosive PSR events in which most of the energy stored in |e> is released within a few nanoseconds. The present paper is intended to be self-contained explaining some details related theoretical works in the past, and further reports new simulations and our ongoing experimental efforts of the project to realize the neutrino mass spectroscopy using atoms/molecules.

Atsushi Fukumi; Susumu Kuma; Yuki Miyamoto; Kyo Nakajima; Itsuo Nakano; Hajime Nanjo; Chiaki Ohae; Noboru Sasao; Minoru Tanaka; Takashi Taniguchi; Satoshi Uetake; Tomonari Wakabayashi; Takuya Yamaguchi; Akihiro Yoshimi; Motohiko Yoshimura

2012-11-21T23:59:59.000Z

288

Neutrino Oscillation Search Neutrino Oscillation Search  

NLE Websites -- All DOE Office Websites (Extended Search)

EPS HEP 2007 MiniBooNE, Part 2: MiniBooNE, Part 2: First Results of the Muon-To-Electron First Results of the Muon-To-Electron Neutrino Oscillation Search Neutrino Oscillation...

289

Particle mixing, flavor condensate and dark energy  

E-Print Network (OSTI)

The mixing of neutrinos and quarks generate a vacuum condensate that, at the present epoch, behaves as a cosmological constant. The value of the dark energy is constrained today by the very small breaking of the Lorentz invariance.

Massimo Blasone; Antonio Capolupo; Giuseppe Vitiello

2009-12-08T23:59:59.000Z

290

Renormalization Group Evolution of Neutrino Parameters in Presence of Seesaw Threshold Effects and Majorana Phases  

E-Print Network (OSTI)

We examine the renormalization group evolution (RGE) for different mixing scenarios in the presence of seesaw threshold effects from high energy scale (GUT) to the low electroweak (EW) scale in the Standard Model (SM) and the Minimal Supersymmetric Standard Model (MSSM). We consider four mixing scenarios namely Tri-Bimaximal Mixing, Bimaximal Mixing, Hexagonal Mixing and Golden Ratio Mixing which come from different flavor symmetries at the GUT scale. All these mixing scenarios give vanishing reactor angle ($\\theta_{13}$) and maximal atmospheric mixing angle. The solar mixing angle has different value for all four cases. In the light of non zero value of $\\theta_{13}$ it becomes interesting to study the present status of these symmetries, i.e. whether they can generate the current neutrino oscillation data at low energy scale or not. We find that the Majorana phases play an important role in the RGE running of these mixing patterns along with the seesaw threshold corrections. We present a comparative study of the RGE of all these mixing scenarios both with and without Majorana CP phases when seesaw threshold corrections are taken into consideration. We find that in the absence of these Majorana phases both the RGE running and seesaw effects may lead to $\\theta_{13}energies both in the SM and the MSSM. However, if the Majorana phases are incorporated to the mixing matrix the running can be enhanced both in the SM and the MSSM. Even by incorporating non zero Majorana CP phases in the SM, we do not get $\\theta_{13}$ in its present 3$\\sigma$ range. The current values of the two mass squared differences and mixing angles including $\\theta_{13}$ can be produced in the MSSM case with tan$\\beta$ = 10 and non zero Majorana CP phases at low energy.

Shivani Gupta; Sin Kyu Kang; C. S. Kim

2014-06-29T23:59:59.000Z

291

Measurement of Atmospheric Neutrino Oscillations with a High-Density Detector  

E-Print Network (OSTI)

We propose an experiment to test the hypothesis that the reported anomaly on atmospheric neutrino fluxes is due to nu_mu nu_x oscillations. It will rely both on a disappearance technique, exploiting the method of the dependence of the event rate on L/E, which was recently shown to be effective for detection of neutrino oscillation and measurement of the oscillation parameters, and on an appearance technique, looking for an excess of muon-less events at high energy produced by upward-going tau neutrinos. The detector will consist of iron planes interleaved by limited streamer tubes. The total mass will be about 30 kt. The possibility of recuperating most of the instrumentation from existing detectors allows to avoid R&D phases and to reduce construction time. In four years of data taking, this experiment will be sensitive to oscillations nu_mu nu_x with Delta m^2 > 10^-4 eV^2 and a mixing near to maximal, and answer the question whether nu_x is a sterile or a tau neutrino.

A. Curioni; G. Mannocchi; L. Periale; P. Picchi; F. Pietropaolo; S. Ragazzi

1998-05-07T23:59:59.000Z

292

Neutrino physics at accelerators  

E-Print Network (OSTI)

Present and future neutrino experiments at accelerators are mainly concerned with understanding the neutrino oscillation phenomenon and its implications. Here a brief account of neutrino oscillations is given together with a description of the supporting data. Some current and planned accelerator neutrino experiments are also explained.

Enrique Fernandez

2006-07-16T23:59:59.000Z

293

Muons and Neutrinos 2007  

E-Print Network (OSTI)

This paper is the written version of the rapporteur talk on Section HE-2, muons and neutrinos, presented at the 30th International Cosmic Ray Conference, Merida, Yucatan, July 11, 2007. Topics include atmospheric muons and neutrinos, solar neutrinos and astrophysical neutrinos as well as calculations and instrumentation related to these topics.

Thomas K. Gaisser

2008-01-29T23:59:59.000Z

294

Neutrinoless double ? decay with composite neutrinos  

Science Journals Connector (OSTI)

We study in detail the contribution of heavy composite Majorana neutrinos to neutrinoless double beta decay (0???). Our analysis confirms the result of a previous estimate by two of the authors. Excited neutrinos couple to the electroweak gauge bosons through a magnetic-type effective Lagrangian. The relevant nuclear matrix element is related to matrix elements available in the literature and current bounds on the half-life of 0??? are converted into bounds on the compositeness scale and/or the heavy neutrino mass. Our bounds are of the same order of magnitude as those available from accelerator experiments.

O. Panella; C. Carimalo; Y. N. Srivastava; A. Widom

1997-11-01T23:59:59.000Z

295

The particle world - neutrinos | U.S. DOE Office of Science (SC)  

Office of Science (SC) Website

What are neutrinos telling us? What are neutrinos telling us? NuMI/MINOS NuMI is a facility at Fermilab that produces an intense beam of neutrinos for MINOS, an experiment that promises to unlock the many secrets of this most mysterious particle. (Credit: Fermilab) Tools for a scientific revolution The discovery that neutrinos have mass opens a window on physics beyond the Standard Model. The Standard Model cannot accommodate neutrino masses without the introduction of new particles, which themselves raise new questions. In fact, the size of the neutrino masses is consistent with expectations from unified theories that require the new particles for the unification itself. The most pressing question about neutrinos involves how many different kinds there are. Results from the Liquid Scintillator Neutrino Detector

296

Dark Matter vs. Neutrinos: The effect of astrophysical uncertainties and timing information on the neutrino floor  

E-Print Network (OSTI)

Future multi-tonne Direct Detection experiments will be sensitive to solar neutrino induced nuclear recoils which form an irreducible background to light Dark Matter searches. Indeed for masses around 6 GeV the spectra of neutrinos and Dark Matter are so similar that experiments will run into a neutrino floor, for which sensitivity increases only marginally with exposure past a certain cross section. In this work we show that this floor can be overcome using the different annual modulation expected from solar neutrinos and Dark Matter. Specifically for cross sections below the neutrino floor the DM signal is observable through a phase shift and a smaller amplitude for the time-dependent event rate. This allows the exclusion power to be improved by up to an order of magnitude for large exposures. In addition we demonstrate that the neutrino floor exists over a wider mass range than has been previously shown, since the large uncertainties in the Dark Matter velocity distribution make the signal spectrum harder to distinguish from the neutrino background. However for most velocity distributions the neutrino floor can still be surpassed using timing information, though certain velocity streams may prove problematic.

Jonathan H. Davis

2014-12-03T23:59:59.000Z

297

Probing light sterile neutrinos in medium baseline reactor experiments  

Science Journals Connector (OSTI)

Medium-baseline reactor experiments (Double Chooz, Daya Bay and RENO) provide a unique opportunity to test the presence of light sterile neutrinos. We analyze the data of these experiments in the search of sterile neutrinos and also test the robustness of ?13 determination in the presence of sterile neutrinos. We show that existence of a light sterile neutrino state improves the fit to these data moderately. We also show that the measured value of ?13 by these experiments is reliable even in the presence of sterile neutrinos, and the reliability owes significantly to the Daya Bay and RENO data. From the combined analysis of the data of these experiments, we constrain the mixing of a sterile neutrino with ?m412?(10-310-1)??eV2 to sin?22?14?0.1 at 95%C.L.

Arman Esmaili; Ernesto Kemp; O. L. G. Peres; Zahra Tabrizi

2013-10-25T23:59:59.000Z

298

Medium effects in string-dilaton-induced neutrino oscillations  

E-Print Network (OSTI)

We consider the unconventional way to interpret the current data on solar neutrino oscillations as derived recently by Halprin and Leung from a string model based on the existence of the string dilaton field which remains massless in the low-energy world. The equivalence principle violation entailed by the existence of a massless dilaton may then produce neutrino oscillations even for neutrinos that are degenerate in mass. Here we calculate the medium-induced mass squared difference for solar neutrinos, which is due to their coherent interactions with the cosmic neutrino background and with solar plasma constituents. We show that this difference can naturally be large enough to satisfy the known experimental limits on the Just So solution as well as on the MSW solution of the solar neutrino problem.

R. Horvat

1998-02-20T23:59:59.000Z

299

The dipion mass spectrum in e+e- annihilation and tau decay: Isospin symmetry breaking effects from the (rho, omega, phi) mixing  

SciTech Connect

A way to explain the puzzling difference between the pion form factor as measured in e{sup +}e{sup -} annihilations and in {tau} decays is discussed. We show that isospin symmetry breaking, beside the already identified effects, produces also a full mixing between the {rho}{sup 0}, {omega} and {phi} mesons which generates an isospin 0 component inside the {rho}{sup 0} meson. This effect, not accounted for in current treatments of the problem, seems able to account for the apparent mismatch between e{sup +}e{sup -} and {tau} data below the {phi} mass.

Benayoun, M.; David, P.; Del Buono, L.; /Paris U., VI-VII; Leitner, O.; /Paris U., VI-VII /Frascati; O'Connell, H.B.; /Fermilab

2008-01-01T23:59:59.000Z

300

Non-linear evolution of the cosmic neutrino background  

SciTech Connect

We investigate the non-linear evolution of the relic cosmic neutrino background by running large box-size, high resolution N-body simulations which incorporate cold dark matter (CDM) and neutrinos as independent particle species. Our set of simulations explore the properties of neutrinos in a reference ?CDM model with total neutrino masses between 0.05-0.60 eV in cold dark matter haloes of mass 10{sup 11}?10{sup 15} h{sup ?1}M{sub s}un, over a redshift range z = 0?2. We compute the halo mass function and show that it is reasonably well fitted by the Sheth-Tormen formula, once the neutrino contribution to the total matter is removed. More importantly, we focus on the CDM and neutrino properties of the density and peculiar velocity fields in the cosmological volume, inside and in the outskirts of virialized haloes. The dynamical state of the neutrino particles depends strongly on their momentum: whereas neutrinos in the low velocity tail behave similarly to CDM particles, neutrinos in the high velocity tail are not affected by the clustering of the underlying CDM component. We find that the neutrino (linear) unperturbed momentum distribution is modified and mass and redshift dependent deviations from the expected Fermi-Dirac distribution are in place both in the cosmological volume and inside haloes. The neutrino density profiles around virialized haloes have been carefully investigated and a simple fitting formula is provided. The neutrino profile, unlike the cold dark matter one, is found to be cored with core size and central density that depend on the neutrino mass, redshift and mass of the halo, for halos of masses larger than ? 10{sup 13.5}h{sup ?1}M{sub s}un. For lower masses the neutrino profile is best fitted by a simple power-law relation in the range probed by the simulations. The results we obtain are numerically converged in terms of neutrino profiles at the 10% level for scales above ? 200 h{sup ?1}kpc at z = 0, and are stable with respect to box-size and starting redshift of the simulation. Our findings are particularly important in view of upcoming large-scale structure surveys, like Euclid, that are expected to probe the non-linear regime at the percent level with lensing and clustering observations.

Villaescusa-Navarro, Francisco; Viel, Matteo [INAF/Osservatorio Astronomico di Trieste, Via Tiepolo 11, 34143, Trieste (Italy); Bird, Simeon [Institute for Advanced Study, 1 Einstein Drive, Princeton, NJ, 08540 (United States); Pea-Garay, Carlos, E-mail: villaescusa@oats.inaf.it, E-mail: spb@ias.edu, E-mail: penya@ific.uv.es, E-mail: viel@oats.inaf.it [Instituto de Fsica Corpuscular, CSIC-UVEG, E-46071, Paterna, Valencia (Spain)

2013-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "neutrino mass mixing" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Modeling the Mass Transfer of Hydrophobic Organic Pollutants in Briefly and Continuously Mixed Sediment after Amendment with Activated Carbon  

Science Journals Connector (OSTI)

Sarah E. Hale and David Werner * ... PAHs were quantified by gas chromatography mass spectrometry and details of these methods can be found in SI pages S3 and S7, respectively. ...

Sarah E. Hale; David Werner

2010-04-14T23:59:59.000Z

302

CP violation in seesaw models of quark masses  

Science Journals Connector (OSTI)

CP phenomenology in seesaw models of quark masses is shown to parallel that of the usual left-right-symmetric models with the additional advantage that it provides a natural solution to the strong CP problem. For the case where the third-generation mixing parameter Vub is extremely small, the neutral-Higgs-boson interactions lead to ?/??10-3 and the electric dipole moment of the neutron dn?10-25 e cm. Smallness of the neutrino masses is understood as a two-loop effect.

K. S. Babu and Rabindra N. Mohapatra

1989-03-06T23:59:59.000Z

303

Neutrinoless ?? decay transition matrix elements within mechanisms involving light Majorana neutrinos, classical Majorons, and sterile neutrinos  

Science Journals Connector (OSTI)

In the projected-Hartree-Fock-Bogoliubov (PHFB) model, uncertainties in the nuclear transition matrix elements for the neutrinoless double-? decay of 94,96Zr, 98,100Mo, 104Ru, 110Pd, 128,130Te, and 150Nd isotopes within mechanisms involving light Majorana neutrinos, classical Majorons, and sterile neutrinos are statistically estimated by considering sets of 16 (24) matrix elements calculated with four different parametrizations of the pairing plus multipolar type of effective two-body interaction, two sets of form factors, and two (three) different parametrizations of Jastrow type of short-range correlations. In the mechanisms involving the light Majorana neutrinos and classical Majorons, the maximum uncertainty is about 15% and in the scenario of sterile neutrinos, it varies in between approximately 4 (9)%20 (36)% without(with) Jastrow short range correlations with the Miller-Spencer parametrization, depending on the considered mass of the sterile neutrinos.

P. K. Rath, R. Chandra, K. Chaturvedi, P. Lohani, P. K. Raina, and J. G. Hirsch

2013-12-20T23:59:59.000Z

304

Patterns in the fermion mixing matrix, a bottom-up approach  

SciTech Connect

We first obtain the most general and compact parametrization of the unitary transformation diagonalizing any 3x3 Hermitian matrix H, as a function of its elements and eigenvalues. We then study a special class of fermion mass matrices, defined by the requirement that all of the diagonalizing unitary matrices (in the up, down, charged lepton, and neutrino sectors) contain at least one mixing angle much smaller than the other two. Our new parametrization allows us to quickly extract information on the patterns and predictions emerging from this scheme. In particular we find that the phase difference between two elements of the two mass matrices (of the sector in question) controls the generic size of one of the observable fermion mixing angles: i.e. just fixing that particular phase difference will predict the generic value of one of the mixing angles, irrespective of the value of anything else.

Couture, Gilles; Hamzaoui, Cherif [Groupe de Physique Theorique des Particules, Departement des Sciences de la Terre et de L'Atmosphere, Universite du Quebec a Montreal, Case Postale 8888, Succ. Centre-Ville, Montreal, Quebec, H3C 3P8 (Canada); Lu, Steven S. Y. [Departement de Mathematiques, Universite du Quebec a Montreal, Case Postale 8888, Succ. Centre-Ville, Montreal, Quebec, H3C 3P8 (Canada); Toharia, Manuel [Maryland Center for Fundamental Physics, Department of Physics, University of Maryland, College Park, Maryland 20742 (United States)

2010-02-01T23:59:59.000Z

305

The Accretion of Solar Material onto White Dwarfs: No Mixing with Core Material Implies that the Mass of the White Dwarf is Increasing  

E-Print Network (OSTI)

Cataclysmic Variables (CVs) are close binary star systems with one component an accreting white dwarf (WD) and the other a larger cooler star that fills its Roche Lobe. One consequence of the WDs accreting material, is the possibility that they are growing in mass and will eventually reach the Chandrasekhar Limit. This evolution could result in a Supernova Ia (SN Ia) explosion and is designated the Single Degenerate Progenitor (SD) scenario. One problem with the single degenerate scenario is that it is generally assumed that the accreting material mixes with WD core material at some time during the accretion phase of evolution and, since the typical WD has a carbon-oxygen (CO) core, the mixing results in large amounts of carbon and oxygen being brought up into the accreted layers. The presence of enriched carbon causes enhanced nuclear fusion and a Classical Nova (CN)explosion. Thus, the WD in a Classical Nova system is decreasing in mass and cannot be a SN Ia progenitor. In new calculations reported here, th...

Starrfield, Sumner

2015-01-01T23:59:59.000Z

306

Report of the Solar and Atmospheric Neutrino Working Group  

SciTech Connect

The highest priority of the Solar and Atmospheric Neutrino Experiment Working Group is the development of a real-time, precision experiment that measures the pp solar neutrino flux. A measurement of the pp solar neutrino flux, in comparison with the existing precision measurements of the high energy {sup 8}B neutrino flux, will demonstrate the transition between vacuum and matter-dominated oscillations, thereby quantitatively testing a fundamental prediction of the standard scenario of neutrino flavor transformation. The initial solar neutrino beam is pure {nu}{sub e}, which also permits sensitive tests for sterile neutrinos. The pp experiment will also permit a significantly improved determination of {theta}{sub 12} and, together with other solar neutrino measurements, either a measurement of {theta}{sub 13} or a constraint a factor of two lower than existing bounds. In combination with the essential pre-requisite experiments that will measure the {sup 7}Be solar neutrino flux with a precision of 5%, a measurement of the pp solar neutrino flux will constitute a sensitive test for non-standard energy generation mechanisms within the Sun. The Standard Solar Model predicts that the pp and {sup 7}Be neutrinos together constitute more than 98% of the solar neutrino flux. The comparison of the solar luminosity measured via neutrinos to that measured via photons will test for any unknown energy generation mechanisms within the nearest star. A precise measurement of the pp neutrino flux (predicted to be 92% of the total flux) will also test stringently the theory of stellar evolution since the Standard Solar Model predicts the pp flux with a theoretical uncertainty of 1%. We also find that an atmospheric neutrino experiment capable of resolving the mass hierarchy is a high priority. Atmospheric neutrino experiments may be the only alternative to very long baseline accelerator experiments as a way of resolving this fundamental question. Such an experiment could be a very large scale water Cerenkov detector, or a magnetized detector with flavor and antiflavor sensitivity. Additional priorities are nuclear physics measurements which will reduce the uncertainties in the predictions of the Standard Solar Model, and similar supporting measurements for atmospheric neutrinos (cosmic ray fluxes, magnetic fields, etc.). We note as well that the detectors for both solar and atmospheric neutrino measurements can serve as multipurpose detectors, with capabilities of discovering dark matter, relic supernova neutrinos, proton decay, or as targets for long baseline accelerator neutrino experiments.

Back, H.; Bahcall, J.N.; Bernabeu, J.; Boulay, M.G.; Bowles, T.; Calaprice, F.; Champagne, A.; Freedman, S.; Gai, M.; Galbiati, C.; Gallagher, H.; Gonzalez-Garcia, C.; Hahn, R.L.; Heeger, K.M.; Hime, A.; Jung, C.K.; Klein, J.R.; Koike, M.; Lanou, R.; Learned, J.G.; Lesko, K.T.; Losecco, J.; Maltoni, M.; Mann, A.; McKinsey, D.; Palomares-Ruiz, S.; Pena-Garay, C.; Petcov, S.T.; Piepke, A.; Pitt, M.; Raghavan, R.; Robertson, R.G.H.; Scholberg, K.; Sobel, H.W.; Takeuchi, T.; Vogelaar, R.; Wolfenstein, L.

2004-10-22T23:59:59.000Z

307

Search for heavy Majorana neutrinos in $\\mu^\\pm \\mu^\\pm$+jets events in proton-proton collisions at $\\sqrt{s}$ = 8 TeV  

E-Print Network (OSTI)

A search is performed for heavy Majorana neutrinos (N) using an event signature defined by two muons of the same charge and two jets ($\\mu^\\pm \\mu^\\pm \\mathrm{j j}$). The data correspond to an integrated luminosity of 19.7 fb$^{-1}$ of proton-proton collisions at a center-of-mass energy of 8 TeV, collected with the CMS detector at the CERN LHC. No excess of events is observed beyond the expected standard model background and upper limits are set on $|V_{\\mu\\mathrm{N}}|^2$ as a function of Majorana neutrino mass $\\mathrm{m}_{\\mathrm{N}}$ for masses in the range of 40-500 GeV, where $|V_{\\mu\\mathrm{N}}|$ is the mixing element of the heavy neutrino with the standard model muon neutrino. The limits obtained are $|V_{\\mu\\mathrm{N}}|^2 \\le 0.00470$ for $\\mathrm{m}_{\\mathrm{N}} = 90$ GeV, $|V_{\\mu\\mathrm{N}}|^2 \\le 0.0123$ for $\\mathrm{m}_{\\mathrm{N}} = 200$ GeV, and $|V_{\\mu\\mathrm{N}}|^2 \\le 0.583$ for $\\mathrm{m}_{\\mathrm{N}} = 500$ GeV. These results extend considerably the regions excluded by previous direct s...

CMS Collaboration

2015-01-01T23:59:59.000Z

308

Neutrino energy reconstruction problems and neutrino oscillations  

E-Print Network (OSTI)

We discuss the accuracy of the usual procedure for neutrino energy reconstruction which is based on the quasielastic kinematics. Our results are described in terms of a probability distribution for a real neutrino energy value. Several factors are responsible of the deviations from the reconstructed value. The main one is the multinucleon component of the neutrino interaction which in the case of Cherenkov detectors enters as a quasielastic cross section, increasing the mean neutrino energy which can differ appreciably from the reconstructed value. As an application we derive, for excess electron events attributed to the conversion of muon neutrinos, the true neutrino energy distribution based on the experimental one which is given in terms of the reconstructed value. The result is a reshaping effect. For MiniBooNE the low energy peak is suppressed and shifted at higher energies, which may influence the interpretation in terms of oscillation. For T2K at the Super Kamiokande far detector the reshaping translat...

Martini, M; Chanfray, G

2012-01-01T23:59:59.000Z

309

Radiative emission of neutrino pair free of quantum electrodynamic backgrounds  

E-Print Network (OSTI)

A scheme of quantum electrodynamic (QED) background-free radiative emission of neutrino pair (RENP) is proposed in order to achieve precision determination of neutrino properties so far not accessible. The important point for the background rejection is the fact that the dispersion relation between wave vector along propagating direction in wave guide (and in a photonic-crystal type fiber) and frequency is modified by a discretized non-vanishing effective mass. This effective mass acts as a cutoff of allowed frequencies, and one may select the RENP photon energy region free of all macro-coherently amplified QED processes by choosing the cutoff larger than the mass of neutrinos.

Yoshimura, M; Tanaka, M

2015-01-01T23:59:59.000Z

310

Radiative emission of neutrino pair free of quantum electrodynamic backgrounds  

E-Print Network (OSTI)

A scheme of quantum electrodynamic (QED) background-free radiative emission of neutrino pair (RENP) is proposed in order to achieve precision determination of neutrino properties so far not accessible. The important point for the background rejection is the fact that the dispersion relation between wave vector along propagating direction in wave guide (and in a photonic-crystal type fiber) and frequency is modified by a discretized non-vanishing effective mass. This effective mass acts as a cutoff of allowed frequencies, and one may select the RENP photon energy region free of all macro-coherently amplified QED processes by choosing the cutoff larger than the mass of neutrinos.

M. Yoshimura; N. Sasao; M. Tanaka

2015-01-23T23:59:59.000Z

311

Optimizing Medium Baseline Reactor Neutrino Experiments  

E-Print Network (OSTI)

10 years from now medium baseline reactor neutrino experiments will attempt to determine the neutrino mass hierarchy from the observed antineutrino spectra. In this letter we present the results of more than four million detailed simulations of such experiments, studying the dependence of the probability of successfully determining the hierarchy upon the analysis method, the neutrino mass matrix parameters, reactor flux models and, in particular, combinations of baselines. We show that the strong dependence of the hierarchy determination upon mass differences and flux models found by Qian et al. results from a spurious dependence of the Fourier analysis upon the high energy tail of the reactor spectrum which can be removed by using a weighted Fourier transform. Such experiments necessarily use flux from multiple reactors at distinct baselines, smearing the oscillation signal and thus impeding the determination of the hierarchy. Using the results of our simulations, we determine the optimal baselines and corre...

Ciuffoli, Emilio; Zhang, Xinmin

2013-01-01T23:59:59.000Z

312

Probing neutrino physics with a self-consistent treatment of the weak decoupling, nucleosynthesis, and photon decoupling epochs  

E-Print Network (OSTI)

We show that a self-consistent and coupled treatment of the weak decoupling, big bang nucleosynthesis, and photon decoupling epochs can be used to provide new insights and constraints on neutrino sector physics from high-precision measurements of light element abundances and cosmic microwave background observables. Implications of beyond-standard-model physics in cosmology, especially within the neutrino sector, are assessed by comparing predictions against five observables: the baryon energy density, helium abundance, deuterium abundance, effective number of neutrinos, and sum of the light neutrino mass eigenstates. We give examples for constraints on dark radiation, neutrino rest mass, lepton numbers, and scenarios for light and heavy sterile neutrinos.

Grohs, E; Kishimoto, C T; Paris, M W

2015-01-01T23:59:59.000Z

313

Precision Measurements with High Energy Neutrino Beams  

E-Print Network (OSTI)

Neutrino scattering measurements offer a unique tool to probe the electroweak and strong interactions as described by the Standard Model (SM). Electroweak measurements are accessible through the comparison of neutrino neutral- and charged-current scattering. These measurements are complimentary to other electroweak measurements due to differences in the radiative corrections both within and outside the SM. Neutrino scattering measurements also provide a precise method for measuring the F_2(x,Q^2) and xF_3(x,Q^2 structure functions. The predicted Q^2 evolution can be used to test perturbative Quantum Chromodynamics as well as to measure the strong coupling constant, alpha _s, and the valence, sea, and gluon parton distributions. In addition, neutrino charm production, which can be determined from the observed dimuon events, allows the strange-quark sea to be investigated along with measurements of the CKM matrix element |V_{cd}| and the charm quark mass.

Janet M. Conrad; Michael H. Shaevitz; Tim Bolton

1997-07-03T23:59:59.000Z

314

BNL | Neutrino Research History  

NLE Websites -- All DOE Office Websites (Extended Search)

Brookhaven Neutrino Research Brookhaven Neutrino Research image of neutrinos Tens of billions of neutrinos are passing through every square centimeter of the Earth's surface right now. A Ghost-Particle Retrospective Neutrinos, ghostlike particles that flooded the universe just moments after the Big Bang, are born in the hearts of stars and other nuclear reactions. Untouched by electromagnetism and nearly as fast as light, neutrinos pass practically unhindered through everything from planets to people, only rarely responding to the weak nuclear force and the even weaker gravity. In fact, at any given moment, tens of billions of neutrinos are passing through every square centimeter of the Earth's surface. Neutrino Research News photomultiplier tubes New Results from Daya Bay: Tracking the Disappearance of Ghostlike

315

Tau contributions to muon/electron events at a neutrino factory  

SciTech Connect

The oscillation of the muon and electron neutrinos (anti-neutrinos) to tau neutrinos (anti-neutrinos) adds to the muon and electron events sample (both right sign and wrong sign) via leptonic decays of the taus produced through charge current interactions in the detector. We focus on how this contribution affects a precision measurement of the atmospheric mixing parameters and the deviation of v{sub {mu}} {r_reversible} v{sub {tau}} mixing from maximality. We also comment on the tau contamination in the golden and platinum channels.

Sinha, Nita [Institute of Mathematical Sciences, Chennai 600 113 (India)

2011-10-06T23:59:59.000Z

316

Neutrino Magnetic Moment, CP Violation and Flavor Oscillations in Matter  

E-Print Network (OSTI)

We consider collective oscillations of neutrinos, which are emergent nonlinear flavor evolution phenomena instigated by neutrino-neutrino interactions in astrophysical environments with sufficiently high neutrino densities. We investigate the symmetries of the problem in the full three flavor mixing scheme and in the exact many-body formulation by including the effects of CP violation and neutrino magnetic moment. We show that, similar to the two flavor scheme, several dynamical symmetries exist for three flavors in the single-angle approximation if the net electron background in the environment and the effects of the neutrino magnetic moment are negligible. Moreover, we show that these dynamical symmetries are present even when the CP symmetry is violated in neutrino oscillations. We explicitly write down the constants of motion through which these dynamical symmetries manifest themselves in terms of the generators of the SU(3) flavor transformations. We also show that the effects due to the CP-violating Dirac phase factor out of the many-body evolution operator and evolve independently of nonlinear flavor transformations if neutrino electromagnetic interactions are ignored. In the presence of a strong magnetic field, CP-violating effects can still be considered independently provided that an effective definition for neutrino magnetic moment is used.

Y. Pehlivan; A. B. Balantekin; Toshitaka Kajino

2014-06-19T23:59:59.000Z

317

Solar neutrino experiments  

Science Journals Connector (OSTI)

The main results of solar neutrino experiments are presented, ranging from the pioneering Cl-Ar experiment up to the most recent Borexino data. Solar neutrino fluxes and spectra are given for two versions of the standard solar model, and radiochemical and electronic detectors are briefly described. The results of Be- and pep-neutrino detection by Borexino are presented. The LMA-MSW oscillation solution of the solar neutrino problem is considered.

A V Derbin

2014-01-01T23:59:59.000Z

318

Characterization of submicron particles influenced by mixed biogenic and anthropogenic emissions using high-resolution aerosol mass spectrometry: results from CARES  

SciTech Connect

The Carbonaceous Aerosols and Radiative Effects Study (CARES) took place in the Sacramento Valley of California in summer 2010. We present results obtained at Cool, CA, the T1 site of the project ({approx}40 km downwind of urban emissions from Sacramento), where we deployed an Aerodyne high resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) in parallel with complementary instrumentation to characterize the sources and processes of submicron particles (PM1). Cool is located at the foothill of the Sierra Nevada Mountains, where intense biogenic emissions are periodically mixed with urban outflow transported by daytime southwesterly winds from the Sacramento metropolitan area. The particle mass loading was low (3.0 {micro}gm{sup -3} on average) and dominated by organics (80% of the PM1 mass) followed by sulfate (9.9 %). Organics and sulfate appeared to be externally mixed, as suggested by their different time series (r2 = 0.13) and size distributions. Sulfate showed a bimodal distribution with a droplet mode peaking at {approx}400nm in vacuum aerodynamic diameter (Dva), and a condensation mode at {approx}150 nm, while organics generally displayed a broad distribution in 60-600nm (Dva). New particle formation and growth events were observed almost every day, emphasizing the roles of organics and sulfate in new particle growth, especially that of organics. The organic aerosol (OA) had a nominal formula of C{sub 1}H{sub 1.38}N{sub 0.004}O{sub 0.44}, thus an average organic mass-to-carbon (OM/OC) ratio of 1.70. Two different oxygenated OA (OOA, 90% of total OA mass) and a hydrocarbon-like OA (HOA, 10 %) were identified by Positive matrix factorization (PMF) of the high resolution mass spectra. The more oxidized MO-OOA (O/C = 0.54) corresponded to secondary OA (SOA) primarily influenced by biogenic emissions, while the less oxidized LO-OOA (O/C = 0.42) corresponded to SOA associated with urban transport. The HOA factor corresponded to primary emissions mainly due to local traffic. Twenty three periods of urban plumes from T0 (Sacramento) to T1 (Cool) were identified using the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem). The average PM1 mass loading was much higher in urban plumes (3.9 {micro}gm{sup -3}) than in air masses dominated by biogenic SOA (1.8 {micro}gm{sup -3}). The change in OA mass relative to CO ({Delta}OA/{Delta}CO) varied in the range of 5-196 {micro}gm{sup -3} ppm{sup -1}, reflecting large variability in SOA production. The highest {Delta}OA/{Delta}CO were reached when urban plumes arrived at Cool in the presence of a high concentration of biogenic volatile organic compounds (BVOCs=isoprene+monoterpenes+2-methyl-3-buten-2- ol [MBO]+methyl chavicol). This ratio, which was 77 {micro}gm{sup -3} ppm{sup -1} on average when BVOCs > 2 ppb, is much higher than when urban plumes arrived in a low biogenic VOCs environment (28 {micro}gm{sup -3} ppm{sup -1} when BVOCs < 0.7 ppb) or during other periods dominated by biogenic SOA (40 {micro}gm{sup -3} ppm{sup -1}). The results from this study demon10 strate that SOA formation is enhanced when anthropogenic emissions interact with biogenic precursors.

Setyan, Ari; Zhang, Qi; Merkel, M.; Knighton, Walter B.; Sun, Y.; Song, Chen; Shilling, John E.; Onasch, Timothy B.; Herndon, Scott C.; Worsnop, Douglas R.; Fast, Jerome D.; Zaveri, Rahul A.; Berg, Larry K.; Wiedensohler, A.; Flowers, B. A.; Dubey, Manvendra K.; Subramanian, R.

2012-09-11T23:59:59.000Z

319

Neutrino Astronomy Scott Wilbur  

E-Print Network (OSTI)

V protons, which should be created with neutrinos, have been seen Can be used to observe possible dark Particle Physics Extremely long baseline for neutrino oscillation studies Dark Matter Searches Many dark Detector Picture from AMANDA II Web Site: http://www.amanda.uci.edu #12;Advantages of Neutrino Astronomy

Golwala, Sunil

320

Neutrino Oscillation Appearance Experiment using Nuclear Emulsion and Magnetized Iron  

E-Print Network (OSTI)

This report describes an apparatus that could be used to measure both the identity and charge of an outgoing lepton in a charged current neutrino interaction. This capability in a massive detector would allow the most comprehensive set of neutrino oscillation physics measurements. By measuring the six observable transitions between initial and final state neutrinos, one would be able to measure all elements of the neutrino mixing matrix, as well as search for CP violation, and matter effects. If the measured matrix is not unitary, then one would also have an unambiguous determination of sterile neutrinos. Emulsion is considered as the tracking medium, and different techniques are discussed for the application of a magnetic field.

D. A. Harris; A. Para

2000-01-13T23:59:59.000Z

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321

Citation: K. Nakamura et al. (Particle Data Group), JP G 37, 075021 (2010) and 2011 partial update for the 2012 edition (URL: http://pdg.lbl.gov) Neutrino Mixing  

E-Print Network (OSTI)

, and there were large variations in the reactor power production in Japan in 2003. 3 EGUCHI 03 observe reactor neutrino disappearance at 180 km baseline to various Japanese nuclear power reactors. 4 BOEHM 01 search are not directly comparable because the effective baseline varies with power output of the reactor sources involved

322

Flavor in heavy neutrino searches at the LHC  

Science Journals Connector (OSTI)

Heavy neutrinos at the TeV scale have been searched for at the LHC in the context of left-right models, under the assumption that they couple to the electron, the muon, or both. We show that current searches are also sensitive to heavy neutrinos coupling predominantly to the tau lepton, and present limits can significantly constrain the parameter space of general flavor mixing.

J. A. Aguilar-Saavedra; F. Deppisch; O. Kittel; J. W. F. Valle

2012-05-24T23:59:59.000Z

323

Cosmic neutrino background absorption line in the neutrino spectrum at IceCube  

Science Journals Connector (OSTI)

The IceCube experiment has recently reported a high energy neutrino spectrum between the TeV and PeV scales. The observed neutrino flux can be as a whole well fitted by a simple power law of the neutrino energy E?, E???? (???2). As a notable feature of the spectrum, however, it has a gap between 500TeV and 1PeV. Although the existence of the gap in the neutrino spectrum is not statistically significant at this point, it is very enticing to ask whether it might hint at some physics beyond the Standard Model. In this paper, we investigate a possibility that the gap can be interpreted as an absorption line in the power-law spectrum by the cosmic neutrino background through a new resonance in the MeV range. We also show that the absorption line has rich information about not only the MeV scale new particle but also the neutrino masses as well as the distances to the astrophysical sources of the high energy neutrinos. Viable models to achieve this possibility are also discussed.

Masahiro Ibe and Kunio Kaneta

2014-09-24T23:59:59.000Z

324

Neutrino halos in clusters of galaxies and their weak lensing signature  

SciTech Connect

We study whether non-linear gravitational effects of relic neutrinos on the development of clustering and large-scale structure may be observable by weak gravitational lensing. We compute the density profile of relic massive neutrinos in a spherical model of a cluster of galaxies, for several neutrino mass schemes and cluster masses. Relic neutrinos add a small perturbation to the mass profile, making it more extended in the outer parts. In principle, this non-linear neutrino perturbation is detectable in an all-sky weak lensing survey such as EUCLID by averaging the shear profile of a large fraction of the visible massive clusters in the universe, or from its signature in the general weak lensing power spectrum or its cross-spectrum with galaxies. However, correctly modeling the distribution of mass in baryons and cold dark matter and suppressing any systematic errors to the accuracy required for detecting this neutrino perturbation is severely challenging.

Villaescusa-Navarro, Francisco; Pea-Garay, Carlos [IFIC, Universidad de Valencia-CSIC, E-46071, Valencia (Spain); Miralda-Escud, Jordi [Instituci Catalana de Recerca i Estudis Avanats, Passeig Llus Companys, 23, 08010-Barcelona (Spain); Quilis, Vicent, E-mail: villa@ific.uv.es, E-mail: miralda@icc.ub.es, E-mail: penya@ific.uv.es, E-mail: vicent.quilis@uv.es [Departamento de Astronomia y Astrofsica, Universidad de Valencia, C/ Dr. Moliner, 50, E-46100, Burjassot, Valencia (Spain)

2011-06-01T23:59:59.000Z

325

Is there evidence for sterile neutrinos in IceCube data?  

Science Journals Connector (OSTI)

Data from the Liquid Scintillator Neutrino Detector and Mini-Booster Neutrino experiments, and the revised expectations of the antineutrino flux from nuclear reactors suggest the existence of eV-mass sterile neutrinos. The 3+2 and 1+3+1 scenarios accommodate all relevant short-baseline neutrino data except for the low-energy Mini-Booster Neutrino Experiment anomaly. We analyze the angular distribution of upward going atmospheric neutrino events in the IceCube-40 data set for evidence of sterile neutrinos within these scenarios. Depending on how systematic uncertainties are handled, we find strong evidence for, or weak evidence against sterile neutrinos. We show that future IceCube data will definitively settle the issue.

V. Barger; Y. Gao; D. Marfatia

2012-01-18T23:59:59.000Z

326

BooNE: Booster Neutrino Experiment  

NLE Websites -- All DOE Office Websites (Extended Search)

arXiv:0806.1449 General neutrino fluxes vs true neutrino energy, for MiniBooNE: image:muon neutrino flux image:electron neutrino flux image:final muon and electron neutrino...

327

Heavy sterile neutrinos, entropy and relativistic energy production, and the relic neutrino background  

E-Print Network (OSTI)

We explore the implications of the existence of heavy neutral fermions (i.e., sterile neutrinos) for the thermal history of the early universe. In particular, we consider sterile neutrinos with rest masses in the 100 MeV to 500 MeV range, with couplings to ordinary active neutrinos large enough to guarantee thermal and chemical equilibrium at epochs in the early universe with temperatures T > 1 GeV, but in a range to give decay lifetimes from seconds to minutes. Such neutrinos would decouple early, with relic densities comparable to those of photons, but decay out of equilibrium, with consequent prodigious entropy generation prior to, or during, Big Bang Nucleosynthesis (BBN). Most of the ranges of sterile neutrino rest mass and lifetime considered are at odds with Cosmic Microwave Background (CMB) limits on the relativistic particle contribution to energy density (e.g., as parameterized by N_eff). However, some sterile neutrino parameters can lead to an acceptable N_eff. These parameter ranges are accompanie...

Fuller, George M; Kusenko, Alexander

2011-01-01T23:59:59.000Z

328

MINOS Sterile Neutrino Search  

SciTech Connect

The Main Injector Neutrino Oscillation Search (MINOS) is a long-baseline accelerator neutrino experiment designed to measure properties of neutrino oscillation. Using a high intensity muon neutrino beam, produced by the Neutrinos at Main Injector (NuMI) complex at Fermilab, MINOS makes two measurements of neutrino interactions. The first measurement is made using the Near Detector situated at Fermilab and the second is made using the Far Detector located in the Soudan Underground laboratory in northern Minnesota. The primary goal of MINOS is to verify, and measure the properties of, neutrino oscillation between the two detectors using the {nu}{sub {mu}} {yields} V{sub {tau}} transition. A complementary measurement can be made to search for the existence of sterile neutrinos; an oft theorized, but experimentally unvalidated particle. The following thesis will show the results of a sterile neutrino search using MINOS RunI and RunII data totaling {approx}2.5 x 10{sup 20} protons on target. Due to the theoretical nature of sterile neutrinos, complete formalism that covers transition probabilities for the three known active states with the addition of a sterile state is also presented.

Koskinen, David Jason; /University Coll. London

2009-09-01T23:59:59.000Z

329

A Long Baseline Neutrino Oscillation Experiment Using J-PARC Neutrino Beam and Hyper-Kamiokande  

E-Print Network (OSTI)

Hyper-Kamiokande will be a next generation underground water Cherenkov detector with a total (fiducial) mass of 0.99 (0.56) million metric tons, approximately 20 (25) times larger than that of Super-Kamiokande. One of the main goals of Hyper-Kamiokande is the study of $CP$ asymmetry in the lepton sector using accelerator neutrino and anti-neutrino beams. In this document, the physics potential of a long baseline neutrino experiment using the Hyper-Kamiokande detector and a neutrino beam from the J-PARC proton synchrotron is presented. The analysis has been updated from the previous Letter of Intent [K. Abe et al., arXiv:1109.3262 [hep-ex

Hyper-Kamiokande Working Group; :; K. Abe; H. Aihara; C. Andreopoulos; I. Anghel; A. Ariga; T. Ariga; R. Asfandiyarov; M. Askins; J. J. Back; P. Ballett; M. Barbi; G. J. Barker; G. Barr; F. Bay; P. Beltrame; V. Berardi; M. Bergevin; S. Berkman; T. Berry; S. Bhadra; F. d. M. Blaszczyk; A. Blondel; S. Bolognesi; S. B. Boyd; A. Bravar; C. Bronner; F. S. Cafagna; G. Carminati; S. L. Cartwright; M. G. Catanesi; K. Choi; J. H. Choi; G. Collazuol; G. Cowan; L. Cremonesi; G. Davies; G. De Rosa; C. Densham; J. Detwiler; D. Dewhurst; F. Di Lodovico; S. Di Luise; O. Drapier; S. Emery; A. Ereditato; P. Fernandez; T. Feusels; A. Finch; M. Fitton; M. Friend; Y. Fujii; Y. Fukuda; D. Fukuda; V. Galymov; K. Ganezer; M. Gonin; P. Gumplinger; D. R. Hadley; L. Haegel; A. Haesler; Y. Haga; B. Hartfiel; M. Hartz; Y. Hayato; M. Hierholzer; J. Hill; A. Himmel; S. Hirota; S. Horiuchi; K. Huang; A. K. Ichikawa; T. Iijima; M. Ikeda; J. Imber; K. Inoue; J. Insler; R. A. Intonti; T. Irvine; T. Ishida; H. Ishino; M. Ishitsuka; Y. Itow; A. Izmaylov; B. Jamieson; H. I. Jang; M. Jiang; K. K. Joo; C. K. Jung; A. Kaboth; T. Kajita; J. Kameda; Y. Karadhzov; T. Katori; E. Kearns; M. Khabibullin; A. Khotjantsev; J. Y. Kim; S. B. Kim; Y. Kishimoto; T. Kobayashi; M. Koga; A. Konaka; L. L. Kormos; A. Korzenev; Y. Koshio; W. R. Kropp; Y. Kudenko; T. Kutter; M. Kuze; L. Labarga; J. Lagoda; M. Laveder; M. Lawe; J. G. Learned; I. T. Lim; T. Lindner; A. Longhin; L. Ludovici; W. Ma; L. Magaletti; K. Mahn; M. Malek; C. Mariani; L. Marti; J. F. Martin; C. Martin; P. P. J. Martins; E. Mazzucato; N. McCauley; K. S. McFarland; C. McGrew; M. Mezzetto; H. Minakata; A. Minamino; S. Mine; O. Mineev; M. Miura; J. Monroe; T. Mori; S. Moriyama; T. Mueller; F. Muheim; M. Nakahata; K. Nakamura; T. Nakaya; S. Nakayama; M. Needham; T. Nicholls; M. Nirkko; Y. Nishimura; E. Noah; J. Nowak; H. Nunokawa; H. M. O'Keeffe; Y. Okajima; K. Okumura; S. M. Oser; E. O'Sullivan; R. A. Owen; Y. Oyama; J. Perez; M. Y. Pac; V. Palladino; J. L. Palomino; V. Paolone; D. Payne; O. Perevozchikov; J. D. Perkin; C. Pistillo; S. Playfer; M. Posiadala-Zezula; J. -M. Poutissou; B. Quilain; M. Quinto; E. Radicioni; P. N. Ratoff; M. Ravonel; M. Rayner; A. Redij; F. Retiere; C. Riccio; E. Richard; E. Rondio; H. J. Rose; M. Ross-Lonergan; C. Rott; S. D. Rountree; A. Rubbia; R. Sacco; M. Sakuda; M. C. Sanchez; E. Scantamburlo; K. Scholberg; M. Scott; Y. Seiya; T. Sekiguchi; H. Sekiya; A. Shaikhiev; I. Shimizu; M. Shiozawa; S. Short; G. Sinnis; M. B. Smy; J. Sobczyk; H. W. Sobel; T. Stewart; J. L. Stone; Y. Suda; Y. Suzuki; A. T. Suzuki; R. Svoboda; R. Tacik; A. Takeda; A. Taketa; Y. Takeuchi; H. A. Tanaka; H. K. M. Tanaka; H. Tanaka; R. Terri; L. F. Thompson; M. Thorpe; S. Tobayama; N. Tolich; T. Tomura; C. Touramanis; T. Tsukamoto; M. Tzanov; Y. Uchida; M. R. Vagins; G. Vasseur; R. B. Vogelaar; C. W. Walter; D. Wark; M. O. Wascko; A. Weber; R. Wendell; R. J. Wilkes; M. J. Wilking; J. R. Wilson; T. Xin; K. Yamamoto; C. Yanagisawa; T. Yano; S. Yen; N. Yershov; M. Yokoyama; M. Zito

2015-01-18T23:59:59.000Z

330

Analytical Theory of Neutrino Oscillations in Matter with CP violation  

E-Print Network (OSTI)

We develop an exact analytical formulation of neutrino oscillations in matter within the framework of the Standard Neutrino Model assuming 3 Dirac Neutrinos. Our Hamiltonian formulation, which includes CP violation, leads to expressions for the partial oscillation probabilities that are linear combinations of spherical Bessel functions in the eigenvalue differences. The coefficients of these Bessel functions are polynomials in the neutrino CKM matrix elements, the neutrino mass differences squared, the strength of the neutrino interaction with matter, and the neutrino mass eigenvalues in matter. We give exact closed-form expressions for all partial oscillation probabilities in terms of these basic quantities. Adopting the Standard Neutrino Model, we then examine how the exact expressions for the partial oscillation probabilities might simplify by expanding in one of the small parameters {\\alpha} and sin{\\theta}13 of this model. We show explicitly that for small {\\alpha} and sin{\\theta}13 there are branch points in the analytic structure of the eigenvalues that lead to singular behavior of expansions near the solar and atmospheric resonances. We present numerical calculations that indicate how to use the small-parameter expansions in practice.

Mikkel B. Johnson; Ernest M. Henley; Leonard S. Kisslinger

2015-01-16T23:59:59.000Z

331

NOvA: Exploring Neutrino Mysteries  

SciTech Connect

Neutrinos are a mystery to physicists. They exist in three different flavors and mass states and may be able to give hints about the origins of the matter-dominated universe. A new long-baseline experiment led by Fermilab called NOvA may provide some answers.

Vahle, Tricia; Messier, Mark

2012-09-06T23:59:59.000Z

332

NOvA: Exploring Neutrino Mysteries  

ScienceCinema (OSTI)

Neutrinos are a mystery to physicists. They exist in three different flavors and mass states and may be able to give hints about the origins of the matter-dominated universe. A new long-baseline experiment led by Fermilab called NOvA may provide some answers.

Vahle, Tricia; Messier, Mark

2014-08-12T23:59:59.000Z

333

Particle mixing as possible explanation of the dark energy conundrum  

E-Print Network (OSTI)

The vacuum condensate due to neutrino and quark mixing behaves as a perfect fluid and, at the present epoch, as a cosmological constant. The very small breaking of the Lorentz invariance constrains today the value of the dark energy.

Antonio Capolupo; Giuseppe Vitiello

2009-01-28T23:59:59.000Z

334

A large liquid argon time projection chamber for long-baseline, off-axis neutrino oscillation physics with the NuMI beam  

SciTech Connect

Results from neutrino oscillation experiments in the last ten years have revolutionized the field of neutrino physics. While the overall oscillation picture for three neutrinos is now well established and precision measurements of the oscillation parameters are underway, crucial issues remain. In particular, the hierarchy of the neutrino masses, the structure of the neutrino mixing matrix, and, above all, CP violation in the neutrino sector are the primary experimental challenges in upcoming years. A program that utilizes the newly commissioned NuMI neutrino beamline, and its planned upgrades, together with a high-performance, large-mass detector will be in an excellent position to provide decisive answers to these key neutrino physics questions. A Liquid Argon time projection chamber (LArTPC) [2], which combines fine-grained tracking, total absorption calorimetry, and scalability, is well matched for this physics program. The few-millimeter-scale spatial granularity of a LArTPC combined with dE/dx measurements make it a powerful detector for neutrino oscillation physics. Scans of simulated event samples, both directed and blind, have shown that electron identification in {nu}{sub e} charged current interactions can be maintained at an efficiency of 80%. Backgrounds for {nu}{sub e} appearance searches from neutral current events with a {pi}{sup 0} are reduced well below the {approx} 0.5-1.0% {nu}{sub e} contamination of the {nu}{sub {mu}} beam [3]. While the ICARUS collaboration has pioneered this technology and shown its feasibility with successful operation of the T600 (600-ton) LArTPC [4], a detector for off-axis, long-baseline neutrino physics must be many times more massive to compensate for the low event rates. We have a baseline concept [5] based on the ICARUS wire plane structure and commercial methods of argon purification and housed in an industrial liquefied-natural-gas tank. Fifteen to fifty kton liquid argon capacity tanks have been considered. A very preliminary cost estimate for a 50-kton detector is $100M (unloaded) [6]. Continuing R&D will emphasize those issues pertaining to implementation of this very large scale liquid argon detector concept. Key hardware issues are achievement and maintenance of argon purity in the environment of an industrial tank, the assembly of very large electrode planes, and the signal quality obtained from readout electrodes with very long wires. Key data processing issues include an initial focus on rejection of cosmic rays for a surface experiment. Efforts are underway at Fermilab and a small number of universities in the US and Canada to address these issues with the goal of embarking on the construction of industrial-scale prototypes within one year. One such prototype could be deployed in the MiniBooNE beamline or in the NuMI surface building where neutrino interactions could be observed. These efforts are complementary to efforts around the world that include US participation, such as the construction of a LArTPC for the 2-km detector location at T2K [7]. The 2005 APS neutrino study [1] recommendations recognize that ''The development of new technologies will be essential for further advances in neutrino physics''. In a recent talk to EPP2010, Fermilab director P. Oddone, discussing the Fermilab program, states on his slides: ''We want to start a long term R&D program towards massive totally active liquid Argon detectors for extensions of NOvA''. [8]. As such, we are poised to enlarge our R&D efforts to realize the promise of a large liquid argon detector for neutrino physics.

Finley, D.; Jensen, D.; Jostlein, H.; Marchionni, A.; Pordes, S.; Rapidis, P.A.; /Fermilab; Bromberg, C.; /Michigan State U.; Lu, C.; McDonald, T.; /Princeton U.; Gallagher,; Mann, A.; Schneps, J.; /Tufts U.; Cline, D.; Sergiampietri, F.; Wang, H.; /UCLA; Curioni, A.; Fleming, B.T.; /Yale U.; Menary, S.; /York U., Canada

2005-09-01T23:59:59.000Z

335

Solar neutrino detection  

SciTech Connect

More than 40 years ago, neutrinos where conceived as a way to test the validity of the solar models which tell us that stars are powered by nuclear fusion reactions. The first measurement of the neutrino flux, in 1968 in the Homestake mine in South Dakota, detected only one third of the expected value, originating what has been known as the Solar Neutrino Problem. Different experiments were built in order to understand the origin of this discrepancy. Now we know that neutrinos undergo oscillation phenomenon changing their nature traveling from the core of the Sun to our detectors. In the work the 40 year long saga of the neutrino detection is presented; from the first proposals to test the solar models to last real time measurements of the low energy part of the neutrino spectrum.

Miramonti, Lino [Physics department of Milano University and INFN (Italy)

2009-04-30T23:59:59.000Z

336

Solar neutrino detection  

E-Print Network (OSTI)

More than 40 years ago, neutrinos where conceived as a way to test the validity of the solar models which tell us that stars are powered by nuclear fusion reactions. The first measurement of the neutrino flux, in 1968 in the Homestake mine in South Dakota, detected only one third of the expected value, originating what has been known as the Solar Neutrino Problem. Different experiments were built in order to understand the origin of this discrepancy. Now we know that neutrinos undergo oscillation phenomenon changing their nature traveling from the core of the Sun to our detectors. In the work the 40 year long saga of the neutrino detection is presented; from the first proposals to test the solar models to last real time measurements of the low energy part of the neutrino spectrum.

Lino Miramonti

2009-01-22T23:59:59.000Z

337

Nucleosynthesis in neutrino-driven, aspherical supernovae of population III stars  

SciTech Connect

We examine explosive nucleosynthesis during neutrino-driven, aspherical supernovae of Population III stars, based on two-dimensional (2D) hydrodynamic simulations of the explosion of 11-40M{sub Circled-Dot-Operator} stars with zero metallicity. The magnitude and asymmetry of the explosion energy are estimated with the simulations. By post-processing calculations with a large nuclear reaction network, we have evaluated abundances and masses of ejecta from the aspherical SNe. We find that the evaluated abundance patterns are similar to those observed in extremely metal poor stars, as shown in spherical and 2D models, in which the explosion is manually and spherically initiated. Matter mixing induced via standing accretion shock instability is important for the abundances and masses of the SN ejecta.

Fujimoto, Shin-ichiro; Hashimoto, Masa-aki; Ono, Masaomi; Kotake, Kei [Kumamoto National College of Technology, 2659-2 Suya, Goshi 861-1102 (Japan); Department of Physics, School of Sciences, Kyushu University, Fukuoka 810-8560 (Japan); Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto 606-8502 (Japan); National Astronomical Observatory Japan, 2-21-1, Osawa, Mitaka, Tokyo, 181-8588 (Japan)

2012-11-12T23:59:59.000Z

338

Neutrinos: Nature's Ghosts?  

ScienceCinema (OSTI)

Dr. Don Lincoln introduces one of the most fascinating inhabitants of the subatomic realm: the neutrino. Neutrinos are ghosts of the microworld, almost not interacting at all. In this video, he describes some of their properties and how they were discovered. Studies of neutrinos are expected to be performed at many laboratories across the world and to form one of the cornerstones of the Fermilab research program for the next decade or more.

Lincoln, Don

2014-08-12T23:59:59.000Z

339

Neutrinos: Nature's Ghosts?  

SciTech Connect

Dr. Don Lincoln introduces one of the most fascinating inhabitants of the subatomic realm: the neutrino. Neutrinos are ghosts of the microworld, almost not interacting at all. In this video, he describes some of their properties and how they were discovered. Studies of neutrinos are expected to be performed at many laboratories across the world and to form one of the cornerstones of the Fermilab research program for the next decade or more.

Lincoln, Don

2013-06-18T23:59:59.000Z

340

Neutrino energy reconstruction problems and neutrino oscillations  

Science Journals Connector (OSTI)

We discuss the accuracy of the usual procedure for neutrino energy reconstruction which is based on the quasielastic kinematics. Our results are described in terms of a probability distribution for a real neutrino energy value. Several factors are responsible for the deviations from the reconstructed value. The main one is the multinucleon component of the neutrino interaction which in the case of Cherenkov detectors enters as a quasielastic cross section, increasing the mean neutrino energy which can differ appreciably from the reconstructed value. As an application we derive, for excess electron events attributed to the conversion of muon neutrinos, the true neutrino energy distribution based on the experimental one which is given in terms of the reconstructed value. The result is a reshaping effect. For MiniBooNE the low energy peak is suppressed and shifted at higher energies, which may influence the interpretation in terms of oscillation. For T2K at the Super Kamiokande far detector the reshaping translates into a narrowing of the energy distribution.

M. Martini; M. Ericson; G. Chanfray

2012-05-21T23:59:59.000Z

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341

Neutrino energy reconstruction problems and neutrino oscillations  

E-Print Network (OSTI)

We discuss the accuracy of the usual procedure for neutrino energy reconstruction which is based on the quasielastic kinematics. Our results are described in terms of a probability distribution for a real neutrino energy value. Several factors are responsible of the deviations from the reconstructed value. The main one is the multinucleon component of the neutrino interaction which in the case of Cherenkov detectors enters as a quasielastic cross section, increasing the mean neutrino energy which can differ appreciably from the reconstructed value. As an application we derive, for excess electron events attributed to the conversion of muon neutrinos, the true neutrino energy distribution based on the experimental one which is given in terms of the reconstructed value. The result is a reshaping effect. For MiniBooNE the low energy peak is suppressed and shifted at higher energies, which may influence the interpretation in terms of oscillation. For T2K at the Super Kamiokande far detector the reshaping translates into a narrowing of the energy distribution.

M. Martini; M. Ericson; G. Chanfray

2012-02-21T23:59:59.000Z

342

Solar neutrino physics: Sensitivity to light dark matter particles  

E-Print Network (OSTI)

Neutrinos are produced in several neutrino nuclear reactions of the proton-proton chain and carbon-nitrogen-oxygen cycle that take place at different radius of the Sun's core. Hence, measurements of solar neutrino fluxes provide a precise determination of the local temperature. The accumulation of non-annihilating light dark matter particles (with masses between 5 GeV and 16 GeV in the Sun produces a change in the local solar structure, namely, a decrease in the central temperature of a few percent. This variation depends on the properties of the dark matter particles, such as the mass of the particle and its spin-independent scattering cross-section on baryon-nuclei, specifically, the scattering with helium, oxygen, and nitrogen among other heavy elements. This temperature effect can be measured in almost all solar neutrino fluxes. In particular, by comparing the neutrino fluxes generated by stellar models with current observations, namely 8B neutrino fluxes, we find that non-annihilating dark matter particles with a mass smaller than 10 GeV and a spin-independent scattering cross-section with heavy baryon-nuclei larger than 3 x 10^{-37} cm^-2 produce a variation in the 8B neutrino fluxes that would be in conflict with current measurements.

Ilidio Lopes; Joseph Silk

2013-09-29T23:59:59.000Z

343

Atmospheric Neutrino Fluxes  

E-Print Network (OSTI)

Starting with an historical review, I summarize the status of calculations of the flux of atmospheric neutrinos and how they compare to measurements.

Thomas K. Gaisser

2005-02-18T23:59:59.000Z

344

Measurement of the ?e and total 8B solar neutrino fluxes with the Sudbury Neutrino Observatory phase-III data set  

Science Journals Connector (OSTI)

This paper details the solar neutrino analysis of the 385.17-day phase-III data set acquired by the Sudbury Neutrino Observatory (SNO). An array of 3He proportional counters was installed in the heavy-water target to measure precisely the rate of neutrino-deuteron neutral-current interactions. This technique to determine the total active 8B solar neutrino flux was largely independent of the methods employed in previous phases. The total flux of active neutrinos was measured to be 5.54?0.31+0.33(stat.)?0.34+0.36(syst.)106cm?2s?1, consistent with previous measurements and standard solar models. A global analysis of solar and reactor neutrino mixing parameters yielded the best-fit values of ?m2=7.59?0.21+0.1910?5eV2 and ?=34.4?1.2+1.3degrees.

B. Aharmim et al. (SNO Collaboration)

2013-01-18T23:59:59.000Z

345

Scalar neutrinos at the LHC  

Science Journals Connector (OSTI)

We study a softly broken supersymmetric model whose gauge symmetry is that of the standard model gauge group times an extra Abelian symmetry U(1)?. We call this gauge-extended model the U(1)? model, and we study a U(1)? model with a secluded sector such that neutrinos acquire Dirac masses via higher-dimensional terms allowed by the U(1)? invariance. In this model the ? term of the minimal supersymmetric model (MSSM) is dynamically induced by the vacuum expectation value of a singlet scalar. In addition, the model contains exotic particles necessary for anomaly cancellation, and extra singlet bosons for achieving correct Z?/Z mass hierarchy. The neutrinos are charged under U(1)?, and thus, their production and decay channels differ from those in the MSSM in strength and topology. We implement the model into standard packages and perform a detailed analysis of sneutrino production and decay at the Large Hadron Collider, for various mass scenarios, concentrating on three types of signals: (1)0?+MET, (2)2?+MET, and (3)4?+MET. We compare the results with those of the MSSM whenever possible, and analyze the standard model background for each signal. The sneutrino production and decays provide clear signatures enabling distinction of the U(1)? model from the MSSM at the LHC.

Durmu? A. Demir; Mariana Frank; Levent Selbuz; Ismail Turan

2011-05-03T23:59:59.000Z

346

Neutrino dark energy-revisiting the stability issue  

SciTech Connect

A coupling between a light scalar field and neutrinos has been widely discussed as a mechanism for linking (time varying) neutrino masses and the present energy density and equation of state of dark energy. However, it has been pointed out that the viability of this scenario in the non-relativistic neutrino regime is threatened by the strong growth of hydrodynamic perturbations associated with a negative adiabatic sound speed squared. In this paper we revisit the stability issue in the framework of linear perturbation theory in a model independent way. The criterion for the stability of a model is translated into a constraint on the scalar-neutrino coupling, which depends on the ratio of the energy densities in neutrinos and cold dark matter. We illustrate our results by providing meaningful examples for both stable and unstable models.

Bjaelde, Ole Eggers; Hannestad, Steen [Department of Physics and Astronomy, University of Aarhus, Ny Munkegade, DK-8000 Aarhus C (Denmark); Brookfield, Anthony W; Van de Bruck, Carsten [Department of Applied Mathematics, Astro-Particle Theory and Cosmology Group, Hounsfield Road, Hicks Building, University of Sheffield, Sheffield S3 7RH (United Kingdom); Mota, David F [Institute for Theoretical Physics, University of Heidelberg, D-69120 Heidelberg (Germany); Schrempp, Lily [Deutsches Elektron-Synchroton DESY, Hamburg, Notkestrasse 85, 22607 Hamburg (Germany); Tocchini-Valentini, Domenico, E-mail: oeb@phys.au.dk, E-mail: php04awb@sheffield.ac.uk, E-mail: C.vandebruck@sheffield.ac.uk, E-mail: sth@phys.au.dk, E-mail: d.mota@thphys.uni-heidelberg.de, E-mail: lily.schrempp@desy.de, E-mail: dtv@skysrv.pha.jhu.edu [Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218 (United States)

2008-01-15T23:59:59.000Z

347

Measurement of the Top Quark Mass using Dilepton Events and a Neutrino Weighting Algorithm with the D0 Experiment at the Tevatron (Run II)  

SciTech Connect

Elementary particle physics raises questions that are several thousand years old. What are the fundamental components of matter and how do they interact? These questions are linked to the question of what happened in the very first moments after the creation of the universe. Modern physics systematically tests nature to find answers to these and other fundamental questions. Precise theories are developed that describe various phenomena and at the same time are reduced to a few basic principals of nature. Simplification and reduction have always been guiding concepts of physics. The interplay between experimental data and theoretical descriptions led to the Standard Model of elementary particle physics. It summarizes the laws of nature and is one of most precise descriptions of nature achieved by mankind. Despite the great success of the Standard Model it is not the ultimate theory of everything. Models beyond the Standard Model try to unify all interactions in one grand unified theory. The number of free parameters is attempted to be reduced. Gravity is attempted to be incorporated. Extensions to the Standard Model like supersymmetry address the so-called hierarchy problem. Precision measurements are the key for searches of new particles and new physics. A powerful tool of experimental particle physics are particle accelerators. They provide tests of the Standard Model at smallest scales. New particles are produced and their properties are investigated. In 1995 the heaviest known elementary particle, called top quark, has been discovered at Fermilab. It differs from all other lighter quarks due to the high mass and very short lifetime. This makes the top quark special and an interesting object to be studied. A rich program of top physics at Fermilab investigates whether the top quark is really the particle as described by the Standard Model. The top quark mass is a free parameter of the theory that has been measured precisely. This thesis presents a precise measurement of the top quark mass by the D0 experiment at Fermilab in the dilepton final states. The comparison of the measured top quark masses in different final states allows an important consistency check of the Standard Model. Inconsistent results would be a clear hint of a misinterpretation of the analyzed data set. With the exception of the Higgs boson, all particles predicted by the Standard Model have been found. The search for the Higgs boson is one of the main focuses in high energy physics. The theory section will discuss the close relationship between the physics of the Higgs boson and the top quark.

Meyer, Joerg; /Bonn U.

2007-01-01T23:59:59.000Z

348

Neutrino oscillations and the number of neutrino types  

Science Journals Connector (OSTI)

A brief treatment of neutrino oscillations, generalized to an arbitrary number of neutrino types, is given as the basis for design of a feasible experiment to search for neutrino oscillations using the neutrino beam produced at a high-energy proton accelerator.

A. K. Mann and H. Primakoff

1977-02-01T23:59:59.000Z

349

Neutrino Counter Nuclear Weapon  

E-Print Network (OSTI)

Radiations produced by neutrino-antineutrino annihilation at the Z0 pole can be used to heat up the primary stage of a thermonuclear warhead and can in principle detonate the device remotely. Neutrino-antineutrino annihilation can also be used as a tactical assault weapon to target hideouts that are unreachable by conventional means.

Tang, Alfred

2008-01-01T23:59:59.000Z

350

Solar Neutrino Physics  

SciTech Connect

With its heavy water target, the Sudbury Neutrino Observatory (SNO) offers the unique opportunity to measure both the 8B flux of electron neutrinos from the Sun and, independently, the flux of all active neutrino species reaching the Earth. A model-independent test of the hypothesis that neutrino oscillations are responsible for the observed solar neutrino deficit can be made by comparing the charged-current (CC) and neutral-current (NC) rates. This LDRD proposal supported the research and development necessary for an assessment of backgrounds and performance of the SNO detector and the ability to extract the NC/CC-Ratio. Particular emphasis is put upon the criteria for deployment and signal extraction from a discrete NC detector array based upon ultra-low background 3He proportional counters.

Bowles, T.J.; Brice, S.J.; Esch, E.-I.; Fowler, M.M.; Goldschmidt, A.; Hime, A.; McGirt, F.; Miller, G.G.; Thornewell, P.M.; Wilhelmy, J.B.; Wouters, J.M.

1999-07-15T23:59:59.000Z

351

Measurement of Atmospheric Neutrino Oscillations with IceCube  

Science Journals Connector (OSTI)

We present the first statistically significant detection of neutrino oscillations in the high-energy regime (>20??GeV) from an analysis of IceCube Neutrino Observatory data collected in 2010 and 2011. This measurement is made possible by the low-energy threshold of the DeepCore detector (?20??GeV) and benefits from the use of the IceCube detector as a veto against cosmic-ray-induced muon background. The oscillation signal was detected within a low-energy muon neutrino sample (20100GeV) extracted from data collected by DeepCore. A high-energy muon neutrino sample (100GeV10TeV) was extracted from IceCube data to constrain systematic uncertainties. The disappearance of low-energy upward-going muon neutrinos was observed, and the nonoscillation hypothesis is rejected with more than 5? significance. In a two-neutrino flavor formalism, our data are best described by the atmospheric neutrino oscillation parameters |?m322|=(2.3-0.5+0.6)10-3??eV2 and sin?2(2?23)>0.93, and maximum mixing is favored.

M. G. Aartsen et al. (IceCube Collaboration)

2013-08-19T23:59:59.000Z

352

7Be Solar Neutrino Measurement with KamLAND  

E-Print Network (OSTI)

We report a measurement of the neutrino-electron elastic scattering rate of 862 keV 7Be solar neutrinos based on a 165.4 kton-day exposure of KamLAND. The observed rate is 582 +/- 90 (kton-day)^-1, which corresponds to a 862 keV 7Be solar neutrino flux of (3.26 +/- 0.50) x 10^9 cm^-2s^-1, assuming a pure electron flavor flux. Comparing this flux with the standard solar model prediction and further assuming three flavor mixing, a nu_e survival probability of 0.66 +/- 0.14 is determined from the KamLAND data. Utilizing a global three flavor oscillation analysis, we obtain a total 7Be solar neutrino flux of (5.82 +/- 0.98) x 10^9 cm^-2s^-1, which is consistent with the standard solar model predictions.

A. Gando; Y. Gando; H. Hanakago; H. Ikeda; K. Inoue; K. Ishidoshiro; H. Ishikawa; Y. Kishimoto; M. Koga; R. Matsuda; S. Matsuda; T. Mitsui; D. Motoki; K. Nakajima; K. Nakamura; A. Obata; A. Oki; Y. Oki; M. Otani; I. Shimizu; J. Shirai; A. Suzuki; K. Tamae; K. Ueshima; H. Watanabe; B. D. Xu; S. Yamada; Y. Yamauchi; H. Yoshida; A. Kozlov; Y. Takemoto; S. Yoshida; C. Grant; G. Keefer; D. W. McKee; A. Piepke; T. I. Banks; T. Bloxham; S. J. Freedman; B. K. Fujikawa; K. Han; L. Hsu; K. Ichimura; H. Murayama; T. O'Donnell; H. M. Steiner; L. A. Winslow; D. Dwyer; C. Mauger; R. D. McKeown; C. Zhang; B. E. Berger; C. E. Lane; J. Maricic; T. Miletic; J. G. Learned; M. Sakai; G. A. Horton-Smith; A. Tang; K. E. Downum; K. Tolich; Y. Efremenko; Y. Kamyshkov; O. Perevozchikov; H. J. Karwowski; D. M. Markoff; W. Tornow; J. A. Detwiler; S. Enomoto; K. Heeger; M. P. Decowski

2014-05-23T23:59:59.000Z

353

Optimization of neutrino fluxes for future long baseline neutrino oscillation experiments  

E-Print Network (OSTI)

One of the main goals of the Long Baseline Neutrino Oscillation experiment (LBNO) experiment is to study the L/E behaviour of the electron neutrino appearance probability in order to determine the unknown phase $\\delta_{CP}$. In the standard neutrino 3-flavour mixing paradigm, this parameter encapsulates a possibility of a CP violation in the lepton sector that in turn could help explain the matter-antimatter asymmetry in the universe. In LBNO, the measurement of $\\delta_{CP}$ would rely on the observation of the electron appearance probability in a broad energy range covering the 1$^{st}$ and 2$^{nd}$ maxima of the oscillation probability. An optimization of the energy spectrum of the neutrino beam is necessary to find the best coverage of the neutrino energies of interest. This in general is a complex task that requires exploring a large parameter space describing hadron target and beamline focusing elements. In this paper we will present a numerical approach of finding a solution to this difficult optimiza...

Calviani, M; Galymov, V; Velten, P

2014-01-01T23:59:59.000Z

354

Meter-baseline tests of sterile neutrinos at Daya Bay  

E-Print Network (OSTI)

We explore the sensitivity of an experiment at the Daya Bay site, with a point radioactive source and a few meter baseline, to neutrino oscillations involving one or more eV mass sterile neutrinos. We find that within a year, the entire 3+2 and 1+3+1 parameter space preferred by global fits can be excluded at the 3\\sigma level, and if an oscillation signal is found, the 3+1 and 3+2 scenarios can be distinguished from each other at more than the 3\\sigma level provided one of the sterile neutrinos is lighter than 0.5 eV.

Y. Gao; D. Marfatia

2013-05-07T23:59:59.000Z

355

High energy cosmic rays, gamma rays and neutrinos from AGN  

E-Print Network (OSTI)

The author reviews a model for the emission of high energy cosmic rays, gamma-rays and neutrinos from AGN (Active Galactic Nuclei) that he has proposed since 1985. Further discussion of the knee energy phenomenon of the cosmic ray energy spectrum requires the existence of a heavy particle with mass in the knee energy range. A possible method of detecting such a particle in the Pierre Auger Project is suggested. Also presented is a relation between the spectra of neutrinos and gamma-rays emitted from AGN. This relation can be tested by high energy neutrino detectors such as ICECUBE, the Mediterranean Sea Detector and possibly by the Pierre Auger Project.

Yukio Tomozawa

2008-02-03T23:59:59.000Z

356

Is the solar neutrino deficit energy-dependent?  

E-Print Network (OSTI)

All existing measurements of the solar neutrino flux are compared with the predictions of the most recent solar model by Bahcall and Pinsonneault, modified by introducing the hypothesis of neutrino oscillations with mass differences large enough to render energy-independent any quantity observable on earth. It is concluded that the data are consistent with this hypothesis and that, at least for the time being, any energy-dependence of the solar neutrino deficit must be regarded as just an attractive theoretical possibility, but not as a compelling reality.

G. Conforto; A. Marchionni; F. Martelli; F. Vetrano

1997-08-11T23:59:59.000Z

357

NERSC Global Filesystem Played a Key Role in Discovery of the Last Neutrino  

NLE Websites -- All DOE Office Websites (Extended Search)

NGFS Played a Key NGFS Played a Key Role in Neutrino Finding NERSC Global Filesystem Played a Key Role in Discovery of the Last Neutrino Mixing Angle February 7, 2013 | Tags: High Energy Physics (HEP), NERSC Global Filesystems (NGF), Science Gateways John Hules, JAHules@lbl.gov, +1 510 486 6008 XBD201107-00790-183.jpg Daya Bay Neutrino Facility in China. Photo by Roy Kaltschmidt, Lawrence Berkeley National Laboratory. Discovery of the last neutrino mixing angle - one of Science magazine's top ten breakthroughs of the year 2012 - was announced in March 2012, just a few months after the Daya Bay Neutrino Experiment's first detectors went online in southeast China. Collaborating scientists from China, the United States, the Czech Republic, and Russia were thrilled that their experiment was producing more data than expected, and that a positive

358

Neutrino-neutrino interactions in a supernova and their effect on neutrino flavor conversions  

SciTech Connect

The neutrino-neutrino interactions inside a supernova core give rise to nonlinear collective effects that significantly influence the neutrino flavor conversions inside the star. I shall describe these interactions, the new oscillation phenomena they generate, and their effect on the neutrino fluxes arriving at the earth.

Dighe, Amol [Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005 (India)

2011-11-23T23:59:59.000Z

359

Relic keV sterile neutrinos and reionization  

E-Print Network (OSTI)

A sterile neutrino with mass of several keV can account for cosmological dark matter, as well as explain the observed velocities of pulsars. We show that X-rays produced by the decays of these relic sterile neutrinos can boost the production of molecular hydrogen, which can speed up the cooling of gas and the early star formation, which can, in turn, lead to a reionization of the universe at a high enough redshift to be consistent with the WMAP results.

Peter L. Biermann; Alexander Kusenko

2005-12-31T23:59:59.000Z

360

Cosmology with self-interacting sterile neutrinos and dark matter - A pseudoscalar model  

E-Print Network (OSTI)

Short baseline neutrino oscillation experiments have shown hints of the existence of additional sterile neutrinos in the eV mass range. Such sterile neutrinos are incompatible with cosmology because they suppress structure formation unless they can be prevented from thermalising in the early Universe. Here we present a novel scenario in which both sterile neutrinos and dark matter are coupled to a new, light pseudoscalar. This can prevent thermalisation of sterile neutrinos and make dark matter sufficiently self-interacting to have an impact on galactic dynamics and possibly resolve some of the known problems with the standard cold dark matter scenario. Our model singles out a dimensionless coupling strength for both sterile neutrinos and dark matter in the range $g_s \\sim g_d \\sim 10^{-5}$ and predicts a dark matter particle mass in the MeV range.

Maria Archidiacono; Steen Hannestad; Rasmus Sloth Hansen; Thomas Tram

2014-04-23T23:59:59.000Z

Note: This page contains sample records for the topic "neutrino mass mixing" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Search for Lepton Number Violating Charged Current Processes with Neutrino Beams  

E-Print Network (OSTI)

We propose a new idea to test a class of loop-induced neutrino mass mechanisms by searching for lepton number violating charged current processes with incident of a neutrino beam. The expected rates of these processes are estimated based on some theoretical assumptions. They turn out to be sizable so that detection of such processes could be possible at near detectors in future highly intense neutrino-beam facilities.

Shinya Kanemura; Yoshitaka Kuno; Toshihiko Ota

2012-05-25T23:59:59.000Z

362

The Sun's Interior Metallicity Constrained by Neutrinos  

E-Print Network (OSTI)

Observed solar neutrino fluxes are employed to constrain the interior composition of the Sun. Including the effects of neutrino flavor mixing, the results from Homestake, Sudbury, and Gallium experiments constrain the Mg, Si, and Fe abundances in the solar interior to be within a factor 0.89 to 1.34 of the surface values with 68% confidence. If the O and/or Ne abundances are increased in the interior to resolve helioseismic discrepancies with recent standard solar models, then the nominal interior Mg, Si, and Fe abundances are constrained to a range of 0.83 to 1.24 relative to the surface. Additional research is needed to determine whether the Sun's interior is metal poor relative to its surface.

Guillermo Gonzalez

2006-05-25T23:59:59.000Z

363

Phenomenology of Neutrino Oscillations  

E-Print Network (OSTI)

The phenomenology of solar, atmospheric, supernova and laboratory neutrino oscillations is described. Analytical formulae for matter effects are reviewed. The results from oscillations are confronted with neutrinoless double beta decay.

G. Rajasekaran

2000-04-17T23:59:59.000Z

364

neutrino.html  

NLE Websites -- All DOE Office Websites (Extended Search)

Fall 2000 Fall 2000 Tau Neutrino Evidence Announced at Fermilab This summer scientists at Fermi National Accelerator Laboratory announced the first direct evidence for the subatomic particle, the tau neutrino. The tau is an almost massless particle that carries no electric charge and barely interacts with surrounding matter. Previous experiments showed indirect evidence for its existence, but it had not been observed directly as yet. The tau is the third neutrino of the Standard Model of elementary particles, a theoretical description that groups all particles into three generations. The first electron neutrino was discovered in 1956, the muon in 1962. The Fermilab experiment responsible for the announcement is the Direct Observation of the Nu Tau (DONUT) experiment. DONUT is a collaboration of

365

Measuring Neutrino Interactions  

NLE Websites -- All DOE Office Websites (Extended Search)

Measuring Neutrino Interactions with MiniBooNE R. Tayloe for the MiniBooNE collaboration Physics Department, Indiana University Bloomington, IN 47405, USA Abstract. The MiniBooNE...

366

Daughters mimic sterile neutrinos (almost!) perfectly  

E-Print Network (OSTI)

Since only recently, cosmological observations are sensitive to hot dark matter (HDM) admixtures with sub-eV mass, $m_\\text{hdm}^\\text{eff}$ < eV, that are not fully-thermalised, $N_\\text{eff}$ < 1. We argue that their almost automatic interpretation as a sterile neutrino species is neither from theoretical nor practical parsimony principles preferred over HDM formed by decay products (daughters) of an out-of-equilibrium particle decay. While daughters mimic sterile neutrinos in $N_\\text{eff}$ and $m_\\text{hdm}^\\text{eff}$, there are opportunities to assess this possibility in likelihood analyses. Connecting cosmological parameters and moments of momentum distribution functions, we show that --also in the case of mass-degenerate daughters with indistinguishable main physical effects-- the mimicry breaks down when the next moment, the skewness, is considered. Predicted differences of order one in the root-mean-squares of absolute momenta are too small for current sensitivities.

Jasper Hasenkamp

2014-05-26T23:59:59.000Z

367

What the Right Handed Neutrino Really is?  

E-Print Network (OSTI)

We look into the concept of electric charge quantization in the Standard Model. The role of the vector nature of electromagnetism and that of mass generation by Yukawa coupling is studied. We show how the baryon and the lepton numbers arise naturally in this picture. This points to an unambiguous and fundamental understanding of the actual nature of the right-handed neutrino. This conforms to Wigner's analysis of the irreducible representations of the Poincare group.

Syed Afsar Abbas

2009-12-16T23:59:59.000Z

368

Determining neutrino oscillation parameters from atmospheric muon neutrino disappearance with three years of IceCube DeepCore data  

E-Print Network (OSTI)

We present a measurement of neutrino oscillations via atmospheric muon neutrino disappearance with three years of data of the completed IceCube neutrino detector. DeepCore, a region of denser instrumentation, enables the detection and reconstruction of atmospheric muon neutrinos between 10\\,GeV and 100\\,GeV, where a strong disappearance signal is expected. The detector volume surrounding DeepCore is used as a veto region to suppress the atmospheric muon background. Neutrino events are selected where the detected Cherenkov photons of the secondary particles minimally scatter, and the neutrino energy and arrival direction are reconstructed. Both variables are used to obtain the neutrino oscillation parameters from the data, with the best fit given by $\\Delta m^2_{32}=2.72^{+0.19}_{-0.20}\\times 10^{-3}\\,\\mathrm{eV}^2$ and $\\sin^2\\theta_{23} = 0.53^{+0.09}_{-0.12}$ (normal mass hierarchy assumed). The results are compatible and comparable in precision to those of dedicated oscillation experiments.

Aartsen, M G; Adams, J; Aguilar, J A; Ahlers, M; Ahrens, M; Altmann, D; Anderson, T; Arguelles, C; Arlen, T C; Auffenberg, J; Bai, X; Barwick, S W; Baum, V; Bay, R; Beatty, J J; Tjus, J Becker; Becker, K -H; BenZvi, S; Berghaus, P; Berley, D; Bernardini, E; Bernhard, A; Besson, D Z; Binder, G; Bindig, D; Bissok, M; Blaufuss, E; Blumenthal, J; Boersma, D J; Bohm, C; Bos, F; Bose, D; Bser, S; Botner, O; Brayeur, L; Bretz, H -P; Brown, A M; Brunner, J; Buzinsky, N; Casey, J; Casier, M; Cheung, E; Chirkin, D; Christov, A; Christy, B; Clark, K; Classen, L; Clevermann, F; Coenders, S; Cowen, D F; Silva, A H Cruz; Daughhetee, J; Davis, J C; Day, M; de Andr, J P A M; De Clercq, C; De Ridder, S; Desiati, P; de Vries, K D; de With, M; DeYoung, T; Daz-Vlez, J C; Dunkman, M; Eagan, R; Eberhardt, B; Eichmann, B; Eisch, J; Euler, S; Evenson, P A; Fadiran, O; Fazely, A R; Fedynitch, A; Feintzeig, J; Felde, J; Feusels, T; Filimonov, K; Finley, C; Fischer-Wasels, T; Flis, S; Franckowiak, A; Frantzen, K; Fuchs, T; Gaisser, T K; Gaior, R; Gallagher, J; Gerhardt, L; Gier, D; Gladstone, L; Glsenkamp, T; Goldschmidt, A; Golup, G; Gonzalez, J G; Goodman, J A; Gra, D; Grant, D; Gretskov, P; Groh, J C; Gro, A; Ha, C; Haack, C; Ismail, A Haj; Hallen, P; Hallgren, A; Halzen, F; Hanson, K; Hebecker, D; Heereman, D; Heinen, D; Helbing, K; Hellauer, R; Hellwig, D; Hickford, S; Hill, G C; Hoffman, K D; Hoffmann, R; Homeier, A; Hoshina, K; Huang, F; Huelsnitz, W; Hulth, P O; Hultqvist, K; Hussain, S; Ishihara, A; Jacobi, E; Jacobsen, J; Japaridze, G S; Jero, K; Jlelati, O; Jurkovic, M; Kaminsky, B; Kappes, A; Karg, T; Karle, A; Kauer, M; Keivani, A; Kelley, J L; Kheirandish, A; Kiryluk, J; Kls, J; Klein, S R; Khne, J -H; Kohnen, G; Kolanoski, H; Koob, A; Kpke, L; Kopper, C; Kopper, S; Koskinen, D J; Kowalski, M; Kriesten, A; Krings, K; Kroll, G; Kroll, M; Kunnen, J; Kurahashi, N; Kuwabara, T; Labare, M; Lanfranchi, J L; Larsen, D T; Larson, M J; Lesiak-Bzdak, M; Leuermann, M; Lnemann, J; Madsen, J; Maggi, G; Maruyama, R; Mase, K; Matis, H S; Maunu, R; McNally, F; Meagher, K; Medici, M; Meli, A; Meures, T; Miarecki, S; Middell, E; Middlemas, E; Milke, N; Miller, J; Mohrmann, L; Montaruli, T; Morse, R; Nahnhauer, R; Naumann, U; Niederhausen, H; Nowicki, S C; Nygren, D R; Obertacke, A; Odrowski, S; Olivas, A; Omairat, A; O'Murchadha, A; Palczewski, T; Paul, L; Penek, ; Pepper, J A; Heros, C Prez de los; Pfendner, C; Pieloth, D; Pinat, E; Posselt, J; Price, P B; Przybylski, G T; Ptz, J; Quinnan, M; Rdel, L; Rameez, M; Rawlins, K; Redl, P; Rees, I; Reimann, R; Relich, M; Resconi, E; Rhode, W; Richman, M; Riedel, B; Robertson, S; Rodrigues, J P; Rongen, M; Rott, C; Ruhe, T; Ruzybayev, B; Ryckbosch, D; Saba, S M; Sander, H -G; Sandroos, J; Santander, M; Sarkar, S; Schatto, K; Scheriau, F; Schmidt, T; Schmitz, M; Schoenen, S; Schneberg, S; Schnwald, A; Schukraft, A; Schulte, L; Schulz, O; Seckel, D; Sestayo, Y; Seunarine, S; Shanidze, R; Smith, M W E; Soldin, D; Spiczak, G M; Spiering, C; Stamatikos, M; Stanev, T; Stanisha, N A; Stasik, A; Stezelberger, T; Stokstad, R G; Stl, A; Strahler, E A; Strm, R; Strotjohann, N L; Sullivan, G W; Taavola, H; Taboada, I; Tamburro, A; Tepe, A; Ter-Antonyan, S; Terliuk, A; Tei?, G; Tilav, S; Toale, P A; Tobin, M N; Tosi, D; Tselengidou, M; Unger, E; Usner, M; Vallecorsa, S; van Eijndhoven, N; Vandenbroucke, J; van Santen, J; Vehring, M; Voge, M; Vraeghe, M; Walck, C; Wallraff, M; Weaver, Ch; Wellons, M; Wendt, C; Westerhoff, S; Whelan, B J; Whitehorn, N; Wichary, C; Wiebe, K; Wiebusch, C H; Williams, D R; Wissing, H; Wolf, M; Wood, T R; Woschnagg, K; Xu, D L; Xu, X W; Yanez, J P; Yodh, G; Yoshida, S; Zarzhitsky, P; Ziemann, J; Zoll, M

2014-01-01T23:59:59.000Z

369

Estimate of the Energy of Upgoing Muons with Multiple Coulomb Scattering  

Science Journals Connector (OSTI)

Neutrino oscillations, in a two neutrino mixing scenario, are the most likely solution for the atmospheric neutrino problem [1]. Underground experiments unfold the mass difference ?m 2 = m ...

D. Bakari; Y. Becherini; M. Spurio

2001-01-01T23:59:59.000Z

370

The Final Results from the Sudbury Neutrino Observatory  

ScienceCinema (OSTI)

The Sudbury Neutrino Observatory (SNO) was a water Cherenkov detector dedicated to investigate elementary particles called neutrinos. It successfully took data between 1999 and 2006. The detector was unique in its use of heavy water as a detection medium, permitting it to make a solar model-independent test of solar neutrino mixing. In fact, SNO conclusively showed that solar neutrinos oscillate on their way from the core of the Sun to the Earth. This groundbreaking observation was made during three independent phases of the experiment. Even if data taking ended, SNO is still in a mode of precise determination of the solar neutrino oscillation parameters because all along SNO had developed several methods to tell charged-current events apart from neutral-current events. This ability is crucial for the final and ultimate data analysis of all the phases. The physics reach of a combined three-phase solar analysis will be reviewed together with results and subtleties about solar neutrino physics.

None

2011-04-25T23:59:59.000Z

371

Monochromatic neutrinos generated by dark matter and the see-saw mechanism  

E-Print Network (OSTI)

We study a minimal extension of the Standard Model where a scalar field is coupled to the right handed neutrino responsible for the see-saw mechanism for neutrino masses. In the absence of other couplings, the scalar $A$ has a unique decay mode $A \\rightarrow \

Dudas, Emilian; Olive, Keith

2014-01-01T23:59:59.000Z

372

Intensity of Upward Muon Flux Due to Cosmic-Ray Neutrinos Produced in the Atmosphere  

DOE R&D Accomplishments (OSTI)

Calculations were performed to determine the upward going muon flux leaving the earth's surface after production by cosmic-ray neutrinos in the crust. Only neutrinos produced in the earth's atmosphere are considered. Rates of the order of one per 100 sq m/day might be expected if an intermediate boson exists and has a mass less than 2 Bev. (auth)

Lee, T. D.; Robinson, H.; Schwartz, M.; Cool, R.

1963-06-00T23:59:59.000Z

373

Cosmic and Galactic Neutrino Backgrounds from Thermonuclear Sources  

E-Print Network (OSTI)

We estimate energy spectra and fluxes at the Earth's surface of the cosmic and Galactic neutrino backgrounds produced by thermonuclear reactions in stars. The extra-galactic component is obtained by combining the most recent estimates of the cosmic star formation history and the stellar initial mass function with accurate theoretical predictions of the neutrino yields all over the thermonuclear lifetime of stars of different masses. Models of the structure and evolution of the Milky Way are used to derive maps of the expected flux generated by Galactic sources as a function of sky direction. The predicted neutrino backgrounds depend only slightly on model parameters. In the relevant 50 keV-10 MeV window, the total flux of cosmic neutrinos ranges between 20 and 65 particles per square cm per s. Neutrinos reaching the Earth today have been typically emitted at redshift z~2. Their energy spectrum peaks at E~0.1-0.3 MeV. The energy and entropy densities of the cosmic background are negligible with respect to the thermal contribution of relic neutrinos originated in the early universe. In every sky direction, the cosmic background is outnumbered by the Galactic one, whose integrated flux amounts to 300-1000 particles per square cm per s. The emission from stars in the Galactic disk contributes more than 95 per cent of the signal.

Cristiano Porciani; Silvia Petroni; Giovanni Fiorentini

2003-11-20T23:59:59.000Z

374

Neutrinos from dark matter annihilations at the galactic center  

Science Journals Connector (OSTI)

We discuss the prospects for detection of high energy neutrinos from dark matter (DM) annihilation at the galactic center (GC). Despite the large uncertainties associated with our poor knowledge of the distribution of dark matter in the innermost regions of the Galaxy, we determine an upper limit on the neutrino flux by requiring that the associated gamma-ray emission does not exceed the observed flux. We conclude that a neutrino flux from the GC will not be observable by Antares if dark matter is made of neutralinos with mass smaller than 650GeV, while for heavier neutralinos, corresponding to models that will soon be probed by HESS (high energy stereoscopic system), the upper limit on the neutrino flux is barely above the Antares sensitivity. The detection of a larger flux would either require an alternative explanation, in terms of astrophysical processes, or the adoption of other dark matter candidates, disfavouring the case for neutralinos.

Gianfranco Bertone; Emmanuel Nezri; Jean Orloff; Joseph Silk

2004-09-02T23:59:59.000Z

375

E1 Working Group Summary: Neutrino Factories and Muon Colliders  

E-Print Network (OSTI)

We are in the middle of a time of exciting discovery, namely that neutrinos have mass and oscillate. In order to take the next steps to understand this potential window onto what well might be the mechanism that links the quarks and leptons, we need both new neutrino beams and new detectors. The new beamlines can and should also provide new laboratories for doing charged lepton flavor physics, and the new detectors can and should also provide laboratories for doing other physics like proton decay, supernovae searches, etc. The new neutrino beams serve as milestones along the way to a muon collider, which can answer questions in yet another sector of particle physics, namely the Higgs sector or ultimately the energy frontier. In this report we discuss the current status of neutrino oscillation physics, what other oscillation measurements are needed to fully explore the phenomenon, and finally, what other new physics can be explored as a result of building of these facilities.

D. Harris

2001-11-02T23:59:59.000Z

376

Asymmetric neutrino production in magnetized proto-neutron stars in fully relativistic mean-field approach  

SciTech Connect

We calculate the neutrino production cross-section in the proto-neutron-star matter under a strong magnetic field in the relativistic mean-field approach. We introduce a new parameter-set which can reproduce the 1.96 solar mass neutron star. We find that the production process increases emitted neutrinos along the direction parallel to the magnetic field and decrease those along its opposite direction. It means that resultant asymmetry due to the neutrino absorption and scattering process in the magnetic field becomes larger by the addition of the neutrino production process.

Maruyama, Tomoyuki [College of Bioresource Sciences, Nihon University, Fujisawa 252-8510 (Japan); Kajino, Toshitaka; Hidaka, Jun; Takiwaki, Tomoya [National Astronomical Observatory of Japan, Mitaka, Tokyo 181-8588 (Japan); Yasutake, Nobutoshi [Department of Physics, Chiba Institute of Technology, Narashino 275-0023 (Japan); Kuroda, Takami [Department of Physics, University of Basel, CH-4056 Basel (Switzerland); Cheoun, Myung-Ki [Department of Physics, Soongsil University, Seoul, 156-743 (Korea, Republic of); Ryu, Chung-Yeol [General Education Curriculum Center, Hanyang University, Seoul, 133-791 (Korea, Republic of); Mathews, Grant J. [Center of Astrophysics, Department of Physics, University of Notre Dame, Notre Dame, IN 46556 (United States)

2014-05-02T23:59:59.000Z

377

Advanced Neutrino Sources (Neutrino Factories and Beta Beams)  

E-Print Network (OSTI)

Advanced Neutrino Sources (Neutrino Factories and Beta Beams) · Design · R&D Status · Remaining R Meeting February, 2008 page 1 #12;· The stored beam properties & decay kinematics are well known uncertainties on neutrino flux & spectra are small PRECISION · Initial beams are flavor "pure" (BB) or "tagged

378

What are the neutrino masses. Dark matter  

E-Print Network (OSTI)

The arguments connecting detections of a reason of difficulties of a solution of a problem of a cold dark matter are adduced.

V. P. Efrosinin

2010-07-13T23:59:59.000Z

379

The onset of the bipolar flavor conversion of supernova neutrinos  

E-Print Network (OSTI)

The study of supernova neutrinos result an interesting non-linear phenomenon, consisting of three phases: synchronized oscillation phase, bipolar flavor conversion phase and the phase of spectral split. In the collective oscillation of supernova neutrino the self energy is not a constant but varies adiabatically, which is responsible to have such different phases. In this article the transition point from synchronized oscillation to bipolar phase is studied numerically as well as analytically. The numerical results yielding different graphs depending on different values of possible small but non-vanishing mixing angles show the onset of the bipolar phase from the synchronized phase varies as the mixing angle. But the analytical study in terms of a spinning top model results a unique onset condition, which is independent of the choice of mixing angle. Such discrepancy between numerical results and analytical results is explained properly.

Bhattacharyya, Indranath

2014-01-01T23:59:59.000Z

380

Hidden sterile neutrino and the 2+2 sum rule  

Science Journals Connector (OSTI)

We discuss the oscillations of atmospheric and solar neutrinos into sterile neutrinos in the 2+2 scheme. A zeroth order sum rule requires equal probabilities for oscillation into ?s and ?? in the solar+atmospheric data sample. Data do not favor this claim. Here we use scatter plots to assess the corrections of the zeroth order sum rule when (i) the 44 neutrino mixing matrix assumes its full range of allowed values, and (ii) matter effects are included. We also introduce a related product rule. We find that the sum rule is significantly relaxed, due to both the inclusion of the small mixing angles (which provide a short-baseline contribution) and to matter effects. The product rule is also dramatically altered. The observed relaxation of the sum rule weakens the case against the 2+2 model and the sterile neutrino. To invalidate the 2+2 model, the daunting task of fitting global data with the small mixing angles included seems to be required.

Heinrich Ps; Liguo Song; Thomas J. Weiler

2003-04-25T23:59:59.000Z

Note: This page contains sample records for the topic "neutrino mass mixing" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Method of Fission Product Beta Spectra Measurements for Predicting Reactor Anti-neutrino Emission  

E-Print Network (OSTI)

The nuclear fission process that occurs in the core of nuclear reactors results in unstable, neutron rich fission products that subsequently beta decay and emit electron anti-neutrinos. These reactor neutrinos have served neutrino physics research from the initial discovery of the neutrino to current precision measurements of neutrino mixing angles. The prediction of the absolute flux and energy spectrum of the emitted reactor neutrinos hinges upon a series of seminal papers based on measurements performed in the 1970s and 1980s. The steadily improving reactor neutrino measurement techniques and recent re-considerations of the agreement between the predicted and observed reactor neutrino flux motivates revisiting the underlying beta spectra measurements. A method is proposed to use an accelerator proton beam delivered to an engineered target to yield a neutron field tailored to reproduce the neutron energy spectrum present in the core of an operating nuclear reactor. Foils of the primary reactor fissionable isotopes placed in this tailored neutron flux will ultimately emit beta particles from the resultant fission products. Measurement of these beta particles in a time projection chamber with a perpendicular magnetic field provides a distinctive set of systematic considerations for comparison to the original seminal beta spectra measurements. Ancillary measurements such as gamma-ray emission and post-irradiation radiochemical analysis will further constrain the absolute normalization of beta emissions per fission. The requirements for unfolding the beta spectra measured with this method into a predicted reactor neutrino spectrum are explored.

D. M. Asner; K. Burns; L. W. Campbell; B. Greenfield; M. S. Kos; J. L. Orrell; M. Schram; B. VanDevender; 1 L. S. Wood; D. W. Wootan

2014-03-01T23:59:59.000Z

382

Neutrino oscillations, supersymmetric grand unification, and B decay  

Science Journals Connector (OSTI)

The effects of supersymmetric particles on flavor changing neutral current and lepton flavor violating processes are studied in supersymmetric SU(5) grand unified theory with right-handed neutrino supermultiplets. Using input parameters motivated by neutrino oscillation, it is shown that the time-dependent CP asymmetry of radiative B decay can be as large as 25% when the ???? branching ratio becomes close to the present experimental upper bound. We also show that the BsBs mixing can be significantly different from the presently allowed range in the standard model.

Seungwon Baek; Toru Goto; Yasuhiro Okada; Ken-ichi Okumura

2001-01-23T23:59:59.000Z

383

Supernova Neutrinos Detection On Earth  

E-Print Network (OSTI)

In this paper, we first discuss the detection of supernova neutrino on Earth. Then we propose a possible method to acquire information about $\\theta_{13}$ smaller than $1.5^\\circ$ by detecting the ratio of the event numbers of different flavor supernova neutrinos. Such an sensitivity cannot yet be achieved by the Daya Bay reactor neutrino experiment.

Xin-Heng Guo; Ming-Yang Huang; Bing-Lin Young

2009-05-12T23:59:59.000Z

384

Neutrino Oscillations Experiments at Fermilab  

E-Print Network (OSTI)

Neutrino oscillations provide an unique opportunity to probe physics beyond the Standard Model. Fermilab is constructing two new neutrino beams to provide a decicive test of two of the recent positive indications for neutrino oscillations: MiniBOONE experiment will settle the LSND controversy, MINOS will provide detailed studies of the region indicated by the SuperK results.

Adam Para

2000-05-01T23:59:59.000Z

385

Electromagnetic neutrino: a short review  

E-Print Network (OSTI)

A short review on selected issues related to the problem of neutrino electromagnetic properties is given. After a flash look at the theoretical basis of neutrino electromagnetic form factors, constraints on neutrino magnetic moments and electric millicharge from terrestrial experiments and astrophysical observations are discussed. We also focus on some recent studies of the problem and on perspectives.

Alexander I. Studenikin

2014-11-09T23:59:59.000Z

386

Search for an admixture of sterile neutrino in the electron spectrum from tritium $?$-decay  

E-Print Network (OSTI)

We propose an experiment intended for search for an admixture of sterile neutrino with mass m$_s$ in the range of 1-8 keV that may be detected as specific distortion of the electron energy spectrum during tritium decay. The distortion is spread over large part of the spectrum so to reveal it one can use a detector with relatively poor (near 10-15%) energy resolution. A classic proportional counter is a simple natural choice for a tritium $\\beta$-decay detector. The method we are proposing is original in two respects. First, the counter is produced as a whole from fully-fused quartz tube allowing to measure current pulse directly from anode while providing high stability for a long time. Second, a modern digital acquisition technique can be used in measurements at ultrahigh count rate - up to 10$^6$ Hz. As a result an energy spectrum of tritium electrons containing up to 10$^{12}$ counts may be collected in a month of live time measurements. Due to high statistics an upper limit down to 10$^{-3}$..10$^{-5}$ can be put on sterile neutrino mixing at 95% CL for m$_s$ in the range of 1-8 keV, that will be 1..2 orders of magnitude better then bounds published up to now.

D. Abdurashitov; A. Berlev; N. Likhovid; A. Lokhov; I. Tkachev; V. Yants

2014-03-12T23:59:59.000Z

387

Neutrino flavor ratios as diagnostic of solar WIMP annihilation  

E-Print Network (OSTI)

We consider the neutrino (and antineutrino) flavors arriving at Earth for neutrinos produced in the annihilation of weakly interacting massive particles (WIMPs) in the Sun's core. Solar-matter effects on the flavor propagation of the resulting $\\agt$ GeV neutrinos are studied analytically within a density-matrix formalism. Matter effects, including mass-state level-crossings, influence the flavor fluxes considerably. The exposition herein is somewhat pedagogical, in that it starts with adiabatic evolution of single flavors from the Sun's center, with $\\theta_{13}$ set to zero, and progresses to fully realistic processing of the flavor ratios expected in WIMP decay, from the Sun's core to the Earth. In the fully realistic calculation, non-adiabatic level-crossing is included, as are possible nonzero values for $\\theta_{13}$ and the CP-violating phase $\\delta$. Due to resonance enhancement in matter, nonzero values of $\\theta_{13}$ even smaller than a degree can noticeably affect flavor propagation. Both normal and inverted neutrino-mass hierarchies are considered. Our main conclusion is that measuring flavor ratios (in addition to energy spectra) of $\\agt$ GeV solar neutrinos can provide discrinination between WIMP models. In particular, we demonstrate the flavor differences at Earth for neutrinos from the two main classes of WIMP final states, namely $W^+ W^-$ and 95% $b \\bar{b}$ + 5% $\\tau^+\\tau^-$. Conversely, if WIMP properties were to be learned from production in future accelerators, then the flavor ratios of $\\agt$ GeV solar neutrinos might be useful for inferring $\\theta_{13}$ and the mass hierarchy.

Ralf Lehnert; Thomas J. Weiler

2007-08-08T23:59:59.000Z

388

Plasmon decay to a neutrino pair via neutrino electromagnetic moments in a strongly magnetized medium  

E-Print Network (OSTI)

We calculate the neutrino luminosity of a degenerate electron gas in a strong magnetic field via plasmon decay to a neutrino pair due to neutrino electromagnetic moments and obtain the relative upper bounds on the effective neutrino magnetic moment.

A. V. Borisov; P. E. Sizin

2014-06-12T23:59:59.000Z

389

SUPERNOVA NEUTRINO LIGHT CURVES AND SPECTRA FOR VARIOUS PROGENITOR STARS: FROM CORE COLLAPSE TO PROTO-NEUTRON STAR COOLING  

SciTech Connect

We present a new series of supernova neutrino light curves and spectra calculated by numerical simulations for a variety of progenitor stellar masses (13-50 M {sub Sun }) and metallicities (Z = 0.02 and 0.004), which would be useful for a broad range of supernova neutrino studies, e.g., simulations of future neutrino burst detection by underground detectors or theoretical predictions for the relic supernova neutrino background. To follow the evolution from the onset of collapse to 20 s after the core bounce, we combine the results of neutrino-radiation hydrodynamic simulations for the early phase and quasi-static evolutionary calculations of neutrino diffusion for the late phase, with different values of shock revival time as a parameter that should depend on the still unknown explosion mechanism. We describe the calculation methods and basic results, including the dependence on progenitor models and the shock revival time. The neutrino data are publicly available electronically.

Nakazato, Ken'ichiro; Suzuki, Hideyuki [Department of Physics, Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510 (Japan)] [Department of Physics, Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510 (Japan); Sumiyoshi, Kohsuke [Numazu Collage of Technology, 3600 Ooka, Numazu, Shizuoka 410-8501 (Japan)] [Numazu Collage of Technology, 3600 Ooka, Numazu, Shizuoka 410-8501 (Japan); Totani, Tomonori [Department of Astronomy, Kyoto University, Kita-shirakawa Oiwake-cho, Sakyo, Kyoto 606-8502 (Japan)] [Department of Astronomy, Kyoto University, Kita-shirakawa Oiwake-cho, Sakyo, Kyoto 606-8502 (Japan); Umeda, Hideyuki [Department of Astronomy, University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-0033 (Japan)] [Department of Astronomy, University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-0033 (Japan); Yamada, Shoichi, E-mail: nakazato@rs.tus.ac.jp [Department of Physics, Waseda University, 3-4-1 Okubo, Shinjuku, Tokyo 169-8555 (Japan)] [Department of Physics, Waseda University, 3-4-1 Okubo, Shinjuku, Tokyo 169-8555 (Japan)

2013-03-01T23:59:59.000Z

390

Spectroscopy of Double-Beta and Inverse-Beta Decays from 100Mo for Neutrinos  

E-Print Network (OSTI)

Spectroscopic studies of two beta-rays from 100Mo are shown to be of potential interest for investigating both the Majorana neutrino mass by neutrinoless double beta-decay and low energy solar neutrino's by inverse beta-decay. With a multi-ton 100Mo detector, coincidence studies of correlated beta-beta from neutrinoless double beta-decay, together with the large Q value, permit identification of the neutrino-mass term with a sensitivity of ~ 0.03 eV. Correlation studies of the inverse beta and the successive beta-decay of 100Tc, together with the large capture rates for low energy solar neutrino's, make it possible to detect in realtime individual low energy solar neutrino in the same detector.

H. Ejiri; J. Engel; R. Hazama; P. Krastev; N. Kudomi; R. G. H. Robertson

1999-11-20T23:59:59.000Z

391

Future Accelerators, Muon Colliders, and Neutrino Factories  

SciTech Connect

Particle physics is driven by five great topics. Neutrino oscillations and masses are now at the fore. The standard model with extensions to supersymmetry and a Higgs to generate mass explains much of the field. The origins of CP violation are not understood. The possibility of extra dimensions has raised tantalizing new questions. A fifth topic lurking in the background is the possibility of something totally different. Many of the questions raised by these topics require powerful new accelerators. It is not an overstatement to say that for some of the issues, the accelerator is almost the experiment. Indeed some of the questions require machines beyond our present capability. As this volume attests, there are parts of the particle physics program that have been significantly advanced without the use of accelerators such as the subject of neutrino oscillations and many aspects of the particle-cosmology interface. At this stage in the development of physics, both approaches are needed and important. This chapter first reviews the status of the great accelerator facilities now in operation or coming on within the decade. Next, midrange possibilities are discussed including linear colliders with the adjunct possibility of gamma-gamma colliders, muon colliders, with precursor neutrino factories, and very large hadron colliders. Finally visionary possibilities are considered including plasma and laser accelerators.

Richard A Carrigan, Jr.

2001-12-19T23:59:59.000Z

392

Neutrino experiments and the Large Hadron Collider: friends across 14 orders of magnitude  

E-Print Network (OSTI)

This paper explores some of the questions that connect the Large Hadron Collider (LHC) and neutrino experiments. What is the origin of mass? What is the meaning of flavor? Is there direct evidence of new forces or particles? ...

Conrad, Janet

393

Frederick Reines and the Neutrino  

Office of Scientific and Technical Information (OSTI)

Frederick Reines and the Detection of the Neutrino Frederick Reines and the Detection of the Neutrino Resources with Additional Information '[Frederick] Reines - known among scientists as the "father of neutrino physics" - won the Nobel Prize for physics in 1995 ["for the detection of the neutrino"], nearly 40 years after his neutrino experiments changed the world of physics and set in motion a new way of looking at the universe. ... Frederick Reines Courtesy University of California Irvine Until Reines's discovery, physicists had only theorized the existence of the neutrino - and physicists believed the tiny particles would never be detected. Reines's research laid the groundwork for new avenues of physics inquiry and hundreds of physics experiments that have tested central theories about the structure of our cosmos. The neutrino is one of the tiny spinning particles that are the building blocks of nature. ...

394

Results from the Sudbury Neutrino Observatory Phase III  

SciTech Connect

The third and last phase of the Sudbury Neutrino Observatory (SNO) used a technique independent of previous methods, to measure the rate of neutral-current interactions in heavy water and determine precisely the total active {sup 8}B solar neutrino flux. The total flux obtained is 5.54{sub -0.31}{sup +0.33}(stat){sub -0.34}{sup +0.36}(syst) x 10{sup 6} cm{sup -2}s{sup -1}, in agreement with previous measurements and standard solar models. Results from a global analysis of solar and reactor neutrino give {Delta}m{sup 2} = 7.59{sub -0.21}{sup +0.19} x 10{sup -5} eV{sup 2} and {theta} = 34.4{sub -1.2}{sup +1.3} degrees with a reduced uncertainty on the mixing angle compared to previous phases.

SNO Collaboration; Prior, G.

2008-11-03T23:59:59.000Z

395

Nonstandard neutrino interactions and transition magnetic moments  

We constrain generic nonstandard neutrino interactions with existing experimental data on neutrino transition magnetic moments and derive strong bounds on tensorial couplings of neutrinos to charged fermions. We also discuss how some of these tensorial couplings can be constrained by other experiments, e.g., on neutrino-electron and neutrino-nucleus scattering.

Healey, Kristopher J.; Petrov, Alexey A.; Zhuridov, Dmitry

2013-06-01T23:59:59.000Z

396

Experimental Neutrino Physics  

ScienceCinema (OSTI)

In this talk, I will review how a set of experiments in the last decade has given us our current understanding of neutrino properties. I will show how experiments in the last year or two have clarified this picture, and will discuss how new experiments about to start will address remaining questions. I will particularly emphasizethe relationship between various experimental techniques.

Chris Walter

2010-01-08T23:59:59.000Z

397

Observational Neutrino Astronomy  

Science Journals Connector (OSTI)

...models and nu-clear energy generation in stars...from stars, high-energy neutrino experiments...an Olympic-sized swimming pool. The most impor-tant...VOL. 147 percent efficiency) by the simple pro-cedure...neu-trino of a given energy, incident on a Cl...

John N. Bahcall

1965-01-08T23:59:59.000Z

398

Supernova Simulations with Boltzmann Neutrino Transport: A Comparison of Methods  

E-Print Network (OSTI)

Accurate neutrino transport has been built into spherically symmetric simulations of stellar core collapse and postbounce evolution. The results of such simulations agree that spherically symmetric models with standard microphysical input fail to explode by the delayed, neutrino-driven mechanism. Independent groups implemented fundamentally different numerical methods to tackle the Boltzmann neutrino transport equation. Here we present a direct and detailed comparison of such neutrino radiation-hydrodynamical simulations for two codes, Agile-Boltztran of the Oak Ridge-Basel group and Vertex of the Garching group. The former solves the Boltzmann equation directly by an implicit, general relativistic discrete angle method on the adaptive grid of a conservative implicit hydrodynamics code with second-order TVD advection. In contrast, the latter couples a variable Eddington factor technique with an explicit, moving-grid, conservative high-order Riemann solver with important relativistic effects treated by an effective gravitational potential. The presented study is meant to test both neutrino radiation-hydrodynamics implementations and to provide a data basis for comparisons and verifications of supernova codes to be developed in the future. Results are discussed for simulations of the core collapse and post-bounce evolution of a 13 solar mass star with Newtonian gravity and a 15 solar mass star with relativistic gravity.

M. Liebendoerfer; M. Rampp; H. -Th. Janka; A. Mezzacappa

2003-10-22T23:59:59.000Z

399

Raymond Davis Jr., Solar Neutrinos, and the Solar Neutrino Problems  

Office of Scientific and Technical Information (OSTI)

Raymond Davis, Jr., Solar Neutrinos, Raymond Davis, Jr., Solar Neutrinos, and the Solar Neutrino Problem Resources with Additional Information Raymond Davis, Jr. Photo Courtesy of Brookhaven National Laboratory (BNL) Raymond Davis, Jr., who conducted research in the Chemistry Department at Brookhaven National Laboratory (BNL) from 1948 through 1984, was awarded the 2002 Nobel Prize in Physics "for pioneering contributions to astrophysics, in particular for the detection of cosmic neutrinos." Dr. Davis is also a recipient of the 2003 Fermi Award. He was the first scientist to detect solar neutrinos, ghostlike particles produced in the nuclear reactions that power the sun. "Neutrinos are fascinating particles, so tiny and fast that they can pass straight through everything, even the earth itself, without even slowing down," said Davis. "When I began my work, I was intrigued by the idea of learning something new. The interesting thing about doing new experiments is that you never know what the answer is going to be!"

400

Distinguishing between Dirac and Majorana neutrinos withtwo-particle interferometry  

SciTech Connect

Two-particle interferometry, a second-order interferenceeffect, is explored as another possible tool to distinguish betweenmassive Dirac and Majorana neutrinos. A simple theoretical framework isdiscussed in the context of several gedanken experiments. The method canin principle provide both the mass scale and the quantum nature of theneutrino for a certain class of incoherent left-handed sourcecurrents.

Gutierrez, Thomas D.

2006-03-02T23:59:59.000Z

Note: This page contains sample records for the topic "neutrino mass mixing" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

BooNE: Booster Neutrino Experiment  

NLE Websites -- All DOE Office Websites (Extended Search)

Posters What's a Neutrino? How neutrinos fit into our understanding of the universe. Recipe for a Neutrino Beam Start with some protons... concocting the MiniBooNE beam. The...

402

BooNE: Booster Neutrino Experiment  

NLE Websites -- All DOE Office Websites (Extended Search)

CA A Search for numu Disappearance with SciBooNE and MiniBooNE PowerPoint Z. Pavlovic Low Energy Neutrino Oscillations G. Zeller Neutrino-Nucleus Cross Sections G. Mills Neutrino...

403

On the Detection of the Free Neutrino  

DOE R&D Accomplishments (OSTI)

The experiment previously proposed [to Detect the Free Neutrino] has been initiated, with a Hanford pile as a neutrino source. It appears probable that neutrino detection has been accomplished, and confirmatory work is in progress. (K.S.)

Reines, F.; Cowan, C. L., Jr.

1953-08-06T23:59:59.000Z

404

The role of the induced currents in the mass mechanism of neutrinoless double-beta decay  

Science Journals Connector (OSTI)

The nuclear matrix elements of Majorana neutrino mass mechanism of neutrinoless double-beta decay have so far been calculated using only... ...

George Pantis; Fedor imkovic

2000-04-01T23:59:59.000Z

405

Testing SO(10)-inspired leptogenesis with low energy neutrino experiments  

SciTech Connect

We extend the results of a previous analysis of ours showing that, when both heavy and light flavour effects are taken into account, successful minimal (type I + thermal) leptogenesis with SO(10)-inspired relations is possible. Barring fine tuned choices of the parameters, these relations enforce a hierarchical RH neutrino mass spectrum that results into a final asymmetry dominantly produced by the next-to-lightest RH neutrino decays (N{sub 2} dominated leptogenesis). We present the constraints on the whole set of low energy neutrino parameters. Allowing a small misalignment between the Dirac basis and the charged lepton basis as in the quark sector, the allowed regions enlarge and the lower bound on the reheating temperature gets relaxed to values as low as ? 10{sup 10} GeV. It is confirmed that for normal ordering (NO) there are two allowed ranges of values for the lightest neutrino mass: m{sub 1} ? (1?5) 10{sup ?3} eV and m{sub 1} ? (0.03?0.1) eV. For m{sub 1}?<0.01 eV the allowed region in the plane ?{sub 13}-?{sub 23} is approximately given by ?{sub 23}?<49+0.65 (?{sub 13}?5), while the neutrinoless double beta decay effective neutrino mass falls in the range m{sub ee} = (1?3) 10{sup ?3} eV for ?{sub 13} = (6?11.5). For m{sub 1}?>0.01 eV, one has quite sharply m{sub ee} ? m{sub 1} and an upper bound ?{sub 23}?<46. These constraints will be tested by low energy neutrino experiments during next years. We also find that inverted ordering (IO), though quite strongly constrained, is not completely ruled out. In particular, we find approximately ?{sub 23} ? 43+12 log (0.2 eV/m{sub 1}), that will be fully tested by future experiments.

Bari, Pasquale Di [School of Physics and Astronomy, University of Southampton, Southampton, SO17 1BJ (United Kingdom); Riotto, Antonio, E-mail: P.Di-Bari@soton.ac.uk, E-mail: Antonio.Riotto@cern.ch [INFN, Sezione di Padova, Dipartimento di Fisica Galileo Galilei, Via Marzolo 8, I-35131 Padua (Italy)

2011-04-01T23:59:59.000Z

406

Toward CP-even Neutrino Beam  

E-Print Network (OSTI)

The best method of measuring CP violating effect in neutrino oscillation experiments is to construct and use a neutrino beam made of an ideal mixture of $\\bar{\

A. Fukumi; I. Nakano; H. Nanjo; N. Sasao; S. Sato; M. Yoshimura

2006-12-20T23:59:59.000Z

407

Low-energy solar anti-neutrinos  

E-Print Network (OSTI)

If neutrino conversions within the Sun result in partial polarization of initial solar neutrino fluxes, then a new opportunity arises to observe the anti-\

V. B. Semikoz; S. Pastor; J. W. F. Valle

1998-08-13T23:59:59.000Z

408

Muon colliders and neutrino factories  

SciTech Connect

Over the last decade there has been significant progress in developing the concepts and technologies needed to produce, capture and accelerate {Omicron}(10{sup 21}) muons/year. This development prepares the way for a new type of neutrino source (Neutrino Factory) and a new type of very high energy lepton-antilepton collider (Muon Collider). This article reviews the motivation, design and R&D for Neutrino Factories and Muon Colliders.

Geer, S.; /Fermilab

2010-09-01T23:59:59.000Z

409

Neutrino Factory Feasibility Study  

NLE Websites -- All DOE Office Websites (Extended Search)

6-1 - 6-1 - April 15 th , 2000 6. Cooling 6.1 Introduction The goal of this six-month study is an integrated design for a neutrino source, subject to realistic engineering constraints. As will become evident, the coupling between the cooling-channel design and the design of the upstream components is critical to achieving the best performance. Nevertheless, to make sufficiently rapid progress it has been necessary to design the various components semi-independently, then optimize and iterate to converge towards an integrated design. While we have not yet arrived at a fully optimized design, we have studied sufficiently the cooling channels described below to determine that their performance is limited primarily by the performance of the current phase-rotation and buncher designs. While the designs presented here suffice for an entry-level neutrino factory (10

410

Acoustic detection of neutrinos  

Science Journals Connector (OSTI)

When high energy neutrinosinteract with nucleons in the ocean a jet of hadrons is produced which deposits thermal energy. This thermal energy is expected to produce a sonic pulse which hopefully will be sufficiently intense and directional to enable the energy and direction of incidence of the primary neutrino to be determined [Antares Parvulescu J. Acoust. Soc. Am. 61 580(A) (1977)]. This paper discusses the physical mechanism whereby the energy of the neutrino is converted into a sound pulse. A simple model will be exploited to account for the signature expected from such an event. [Work supported in part by the U. S. Naval Ocean Research and Development Activity and by the U. S. Department of Energy.

Peter J. Westervelt

1978-01-01T23:59:59.000Z

411

Quasivacuum solar neutrino oscillations  

Science Journals Connector (OSTI)

We discuss in detail solar neutrino oscillations with ?m2/E in the range [10-10,10-7]?eV2/MeV. In this range, which interpolates smoothly between the so-called just-so and Mikheyev-Smirnov-Wolfenstein oscillation regimes, neutrino flavor transitions are increasingly affected by matter effects as ?m2/E increases. As a consequence, the usual vacuum approximation has to be improved through the matter-induced corrections, leading to a quasivacuum oscillation regime. We perform accurate numerical calculations of such corrections, using both the true solar density profile and its exponential approximation. Matter effects are shown to be somewhat overestimated in the latter case. We also discuss the role of Earth crossing and of energy smearing. Prescriptions are given to implement the leading corrections in the quasivacuum oscillation range. Finally, the results are applied to a global analysis of solar ? data in a three-flavor framework.

G. L. Fogli; E. Lisi; D. Montanino; A. Palazzo

2000-10-25T23:59:59.000Z

412

Birth of Neutrino Astrophysics  

ScienceCinema (OSTI)

Based mainly on the results of two experiments, KamiokaNDE and Super-KamiokaNDE, the birth of neutrino astrophysics will be described. At the end, the result of the third generation Kamioka experiment, KamLAND, will be discussed together with the future possibilities.Organiser(s): Daniel Treille / EP DivisionNote: * Tea & coffee will be served at 16:00 hrs. Please note unusual day.

None

2011-10-06T23:59:59.000Z

413

ON SOLAR NEUTRINO PROBLEM TIAN MA AND SHOUHONG WANG  

E-Print Network (OSTI)

ON SOLAR NEUTRINO PROBLEM TIAN MA AND SHOUHONG WANG Abstract. The current neutrino oscillation an alternative resolution to the solar neutrino loss problem. Contents 1. Introduction 1 2. Discrepancy of Solar, there are three flavors of neutrinos: the electron neutrino e, the tau neutrino and the mu neutrino µ. The solar

414

Macro-coherent two photon and radiative neutrino pair emission  

E-Print Network (OSTI)

We discuss a possibility of detecting a coherent photon pair emission and related radiative neutrino pair emission from excited atoms. It is shown that atoms of lambda- and ladder-type three level system placed in a pencil-like cylinder give a back to back emission of two photons of equal energy $\\Delta/2$, sharply peaked with a width $\\propto $ 1/(target size) and well collimated along the cylinder axis. This process has a measurable rate $\\propto$ (target number density) $^2 \\times$ target volume, while a broader spectral feature of one-photon distribution separated by (mass sum of a neutrino pair)$^2/(2\\Delta)$ from the two photon peak may arise from radiative neutrino pair emission, with a much smaller rate.

M. Yoshimura; C. Ohae; A. Fukumi; K. Nakajima; I. Nakano; H. Nanjo; N. Sasao

2008-05-14T23:59:59.000Z

415

Big Bang Day: 5 Particles - 4. The Neutrino  

ScienceCinema (OSTI)

Simon Singh looks at the stories behind the discovery of 5 of the universe's most significant subatomic particles: the Electron, the Quark, the Anti-particle, the Neutrino and the "next particle". It's the most populous particle in the universe. Millions of these subatomic particles are passing through each one of us. With no charge and virtually no mass they can penetrate vast thicknesses of matter without any interaction - indeed the sun emits huge numbers that pass through earth at the speed of light. Neutrinos are similar to the more familiar electron, with one crucial difference: neutrinos do not carry electric charge. As a result they're extremely difficult to detect . But like HG Wells' invisible man they can give themselves away by bumping into things at high energy and detectors hidden in mines are exploiting this to observe these rare interactions.

None

2011-04-25T23:59:59.000Z

416

Study of electron-neutrinoelectron elastic scattering at LAMPF  

Science Journals Connector (OSTI)

Neutrino-electron elastic scattering was observed with a 15-ton fine-grained tracking calorimeter exposed to electron neutrinos from muon decay at rest. The measured ?ee-??ee- elastic scattering rate of 23635 events yields the total elastic scattering cross section 10.01.5(stat)0.9(syst)10-45cm2[E?(MeV)], and a model-independent measurement of the strength of the destructive interference between the charged and neutral currents, I=-1.070.21, that agrees well with the standard model (SM) prediction I=-1.08. The agreement between the measured electroweak parameters and SM expectations is used to place limits on neutrino properties, such as neutrino flavor-changing neutral currents and neutrino electromagnetic moments. Limits are placed on the masses of new bosons that interact with leptons: for a neutral tensor boson, MT>105 GeV; for a neutral (pseudo)scalar boson, MP,S>47 GeV; for a charged Higgs boson, M?+>87 GeV; and for a purely left-handed charged (neutral) vector boson, Mx>239(119) GeV.

R. C. Allen; H. H. Chen; P. J. Doe; R. Hausammann; W. P. Lee; X. Q. Lu; H. J. Mahler; M. E. Potter; K. C. Wang; T. J. Bowles; R. L. Burman; R. D. Carlini; D. R. F. Cochran; J. S. Frank; E. Piasetzky; V. D. Sandberg; D. A. Krakauer; R. L. Talaga

1993-01-01T23:59:59.000Z

417

High energy neutrino emission from the earliest gamma-ray bursts  

SciTech Connect

We discuss the high energy neutrino emission from gamma-ray bursts resulting from the earliest generation (''population III'') stars forming in the Universe, whose core collapses into a black hole. These gamma-ray bursts are expected to produce a highly relativistic, magnetically dominated jet, where protons can be accelerated to ultrahigh energies. These interact with the photons produced by the jet, leading to ultrahigh energy photomeson neutrinos as well as secondary leptons and photons. The photon luminosity and the shock properties, and thus the neutrino spectrum, depend on the mass of the black holes as well as on the density of the surrounding external gas. We calculate the individual source neutrino spectral fluxes and the expected diffuse neutrino flux for various source parameters and evolution scenarios. Both the individual and diffuse signals appear detectable in the 1-300 PeV range with current and planned neutrino detectors such as IceCube and ARIANNA, provided the black hole mass is in excess of 30-100 solar masses. This provides a possible test for the debated mass of the progenitor stellar objects, as well as a probe for the early cosmological environment and the formation rate of the earliest structures.

Gao Shan; Toma, Kenji; Meszaros, Peter [Department of Physics, Department of Astronomy and Astrophysics, Center for Particle Astrophysics, Pennsylvania State University, University Park, 16802 (United States)

2011-05-15T23:59:59.000Z

418

Cold plus hot dark matter cosmology in the light of solar and atmospheric neutrino oscillations  

SciTech Connect

We explore the implications of possible neutrino oscillations, as indicated by the solar and atmospheric neutrino experiments, for the cold plus hot dark matter scenario of large-scale structure formation. We find that there are essentially three distinct schemes that can accommodate the oscillation data and which also allow for dark matter neutrinos. These include (i) three nearly degenerate (in mass) neutrinos, (ii) nondegenerate masses with {nu}{sub {tau}} in the eV range, and (iii) a nearly degenerate {nu}{sub {mu}}-{nu}{sub {tau}} pair (in the eV range), with the additional possibility that the electron neutrino is cosmologically significant. The last two schemes invoke a {open_quote}{open_quote}sterile{close_quote}{close_quote} neutrino which is light ({approx_lt}eV). We discuss the implications of these schemes for {bar {nu}}{sub {mu}}-{bar {nu}}{sub {ital e}} and {nu}{sub {mu}}-{nu}{sub {tau}} oscillation, and find that scheme (ii), in particular, predicts them to be in the observable range. As far as structure formation is concerned we compare the one neutrino flavor case with a variety of other possibilities, including two and three degenerate neutrino flavors. We show, both analytically and numerically, the effects of these neutrino mass scenarios on the amplitude of cosmological density fluctuations. With a Hubble constant of 50 km s{sup {minus}}{sup 1} Mpc{sup {minus}}{sup 1}, a spectral index of unity, and {Omega}{sub b}{sub a}{sub r}{sub y}{sub o}{sub n}=0.05, the two and three flavor scenarios fit the observational data marginally better than the single flavor scheme. However, taking account of the uncertainties in these parameters, we show that it is premature to pick a clear winner. {copyright} {ital 1996 The American Physical Society.}

Babu, K.S.; Schaefer, R.K.; Shafi, Q. [Bartol Research Institute, University of Delaware, Newark, Delaware 19716 (United States)] [Bartol Research Institute, University of Delaware, Newark, Delaware 19716 (United States)

1996-01-01T23:59:59.000Z

419

Ultra- and extremely high energy neutrino astronomy  

E-Print Network (OSTI)

Scientific motivations for ultra- and extremely high energy neutrino astronomy are considered. Sources and expected fluxes of EHE/UHE neutrinos are briefly discussed. Operating and planned experiments on astrophysical neutrino detection are reviewed focusing on deep underwater/ice Cherenkov neutrino telescopes.

I. Sokalski

2005-01-05T23:59:59.000Z

420

IceCube: An Instrument for Neutrino Astronomy  

E-Print Network (OSTI)

An Instrument for Neutrino Astronomy Francis Halzen 1 andAn Instrument for Neutrino Astronomy Francis Halzen 1 and94720 Abstract Neutrino astronomy beyond the Sun was first

Halzen, F.

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "neutrino mass mixing" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Microsoft PowerPoint - MiniBooNE Neutrino 2008  

NLE Websites -- All DOE Office Websites (Extended Search)

Oscillation Searches Steve Brice (Fermilab) for the MiniBooNE Collaboration Neutrino 2008 Neutrino 2008 Steve Brice (FNAL) 2 Outline * Electron Neutrino Appearance - Oscillation...

422

Geo-neutrinos: recent developments  

E-Print Network (OSTI)

Radiogenic heating is a key component of the energy balance and thermal evolution of the Earth. It contributes to mantle convection, plate tectonics, volcanoes, and mountain building. Geo-neutrino observations estimate the present radiogenic power of our planet. This estimate depends on the quantity and distribution of heat-producing elements in various Earth reservoirs. Of particular geological importance is radiogenic heating in the mantle. This quantity informs the origin and thermal evolution of our planet. Here we present: currently reported geo-neutrino observations; estimates of the mantle geo-neutrino signal, mantle radiogenic heating, and mantle cooling; a comparison of chemical Earth model predictions of the mantle geo-neutrino signal and mantle radiogenic heating; a brief discussion of radiogenic heating in the core, including calculations of geo-neutrino signals per pW/kg; and finally a discussion of observational strategy.

Dye, Steve

2014-01-01T23:59:59.000Z

423

Bilinear R-parity violating SUSY: Neutrinoless double beta decay in the light of solar and atmospheric neutrino data  

E-Print Network (OSTI)

Neutrinoless double beta ($\\znbb$) decay is considered within bilinear R-parity breaking supersymmetry, including the full one-loop corrections to the neutrino-neutralino mass matrix. Expected rates for $\\znbb$ decay in this model are discussed in light of recent atmospheric and solar neutrino data. We conclude that (a) tree-level calculations for $\\znbb$ decay within the bilinear model are not reliable in the range of parameters preferred by current solar and atmospheric neutrino problems. And (b) if the solar and atmospheric neutrino problems are to be solved within bilinear R-parity violating SUSY the expected rates for $\\znbb$ decay are very low; the effective Majorana neutrino mass at most 0.01 eV and typical values being one order of magnitude lower. Observing $\\znbb$ decay in the next round of experiments therefore would rule out the bilinear R-parity violating supersymmetric model as an explanation for solar and atmospheric neutrino oscillations, as well as any hierarchical scheme for neutrino masses, unless new neutrino interactions are present.

M. Hirsch; J. C. Romao; J. W. F. Valle

2000-04-11T23:59:59.000Z

424

Long-baseline neutrino oscillation experiments and CP violation in the lepton sector  

Science Journals Connector (OSTI)

We discuss possibilities to investigate the effects of CP (and T) violation in the lepton sector in neutrino oscillation experiments. We consider the effects of CP violation in the framework of two schemes of mixing of four massive neutrinos that can accommodate the results of all neutrino oscillation experiments. Using the constraints on the mixing parameters that follow from the results of short-baseline neutrino oscillation experiments, we derive rather strong upper bounds on the effects of CP violation in ?(-)???(-)e transitions in long-baseline neutrino oscillation experiments. We show that the effects of CP violation in ?(-)???(-)? transitions in long-baseline oscillation experiments can be as large as is allowed by the unitarity of the mixing matrix. The matter effects, which complicate the problem of searching for CP violation in long-baseline experiments, are discussed in detail. We consider the T-odd asymmetries whose measurement could allow to reveal T and CP violation in the lepton sector independently from matter effects.

S. M. Bilenky; C. Giunti; W. Grimus

1998-06-12T23:59:59.000Z

425

ANTARES deep sea neutrino telescope results  

SciTech Connect

The ANTARES experiment is currently the largest underwater neutrino telescope in the Northern Hemisphere. It is taking high quality data since 2007. Its main scientific goal is to search for high energy neutrinos that are expected from the acceleration of cosmic rays from astrophysical sources. This contribution reviews the status of the detector and presents several analyses carried out on atmospheric muons and neutrinos. For example it shows the results from the measurement of atmospheric muon neutrino spectrum and of atmospheric neutrino oscillation parameters as well as searches for neutrinos from steady cosmic point-like sources, for neutrinos from gamma ray bursts and for relativistic magnetic monopoles.

Mangano, Salvatore [IFIC - Instituto de Fsica Corpuscular, Edificio Institutos de Investigatin, 46071 Valencia (Spain); Collaboration: ANTARES Collaboration

2014-06-24T23:59:59.000Z

426

White Paper on the Majorana Zero-Neutrino Double-Beta Decay Experiment  

E-Print Network (OSTI)

The objective of the Majorana Experiment is to study neutrinoless double beta decay (0nbb) with an effective Majorana-neutrino mass sensitivity below 50 meV in order to characterize the Majorana nature of the neutrino, the Majorana mass spectrum, and the absolute mass scale. An experimental study of the neutrino mass scale implied by neutrino oscillation results is now technically within our grasp. This exciting physics goal is best pursued using the well-established technique of searching for 0nbb of 76Ge, augmented with recent advances in signal processing and detector design. The Majorana Experiment will consist of a large mass of 76Ge in the form of high-resolution intrinsic germanium detectors located deep underground within a low-background shielding environment. Observation of a sharp peak at the bb endpoint will quantify the 0nbb half-life and thus the effective Majorana mass of the electron neutrino. In addition to the modest R&D program, we present here an overview of the entire project in order to help put in perspective the scope, the low level of technical risk, and the readiness of the Collaboration to immediately begin the undertaking.

The Majorana collaboration

2003-11-13T23:59:59.000Z

427

PPPC 4 DM$?$: A Poor Particle Physicist Cookbook for Neutrinos from DM annihilations in the Sun  

E-Print Network (OSTI)

We provide ingredients and recipes for computing neutrino signals of TeV-scale Dark Matter annihilations in the Sun. For each annihilation channel and DM mass we present the energy spectra of neutrinos at production, including: state-of-the-art energy losses of primary particles in solar matter, secondary neutrinos, electroweak radiation. We then present the spectra after propagation to the Earth, including (vacuum and matter) flavor oscillations and interactions in solar matter. We also provide a numerical computation of the capture rate of DM particles in the Sun. These results are available in numerical form.

Pietro Baratella; Marco Cirelli; Andi Hektor; Joosep Pata; Morten Piibeleht; Alessandro Strumia

2013-12-22T23:59:59.000Z

428

Muon (g-2) from the bulk neutrino field in a warped extra dimensional model  

E-Print Network (OSTI)

In the Randall-Sundrum model, a bulk neutrino field in the 5-dimensional space-time can give rise to tiny Dirac masses to neutrinos. In such a scenario, we have computed the contribution of the bulk neutrino field to the anomalous magnetic moment $(g-2)_\\mu$ of muon. We have computed this contribution in the 't Hooft-Feynman gauge and have found that the contribution has the right sign to fit the current discrepancy between the experiment and the standard model value of $(g-2)_\\mu$. We have also studied possible constraints on the model parameters by including contributions to $(g-2)_\\mu$ from other sources such as bulk gravitons.

R. S. Hundi; Sourov Roy; Soumitra SenGupta

2012-06-22T23:59:59.000Z

429

Energy Dependence of Solar Neutrino Suppression and Bounds on the Neutrino Magnetic Moment  

E-Print Network (OSTI)

An analysis of neutrino electron scattering as applied to the SuperKamiokande solar neutrino experiment with the data from the Homestake experiment leads to an upper bound on the neutrino magnetic moment in the range $\\mu_{\

Joao Pulido; Ana M. Mourao

1998-03-02T23:59:59.000Z

430

Search for muon neutrinos from Gamma-Ray Bursts with the IceCube neutrino telescope  

E-Print Network (OSTI)

of California. Search for muon neutrinos from Gamma-RaySearch for muon neutrinos from Gamma-Ray Bursts with theof searches for high-energy muon neutrinos from 41 gamma-

Abbasi, R.

2010-01-01T23:59:59.000Z

431

7Be Solar Neutrino Measurement with KamLAND  

SciTech Connect

We report a measurement of the neutrino-electron elastic scattering rate of 862 keV {sup 7}Be solar neutrinos based on a 165.4 kton-day exposure of KamLAND. The observed rate is 582{+-}90 (kton#1;day){sup -1}, which corresponds to a 862 keV {sup 7}Be solar neutrino flux of (3.26{+-}0.50) #2;x 10{sup 9} cm{sup -2}s{sup -1}, assuming a pure electron flavor flux. Comparing this flux with the standard solar model prediction and further assuming three flavor mixing, a #23;e survival probability of 0.66{+-}0.14 is determined from the KamLAND data. Utilizing a global three flavor oscillation analysis, we obtain a total {sup 7}Be solar neutrino flux of (5.82{+-}0.98) x 10{sup 9} cm{sup -2}s{sup -1}, which is consistent with the standard solar model predictions.

The KamLAND Collaboration; Gando, A.; Gando, Y.; Hanakago, H.; Ikeda, H.; Inoue, K.; Ishidoshiro, K.; Ishikawa, H.; Kishimoto, Y.; Koga, M.; Matsuda, R.; Matsuda, S.; Mitsui, T.; Motoki, D.; Nakajima, K.; Nakamura, K.; Obata, A.; Oki, A.; Oki, Y.; Otani, M.; Shimizu, I.; Shirai, J.; Suzuki, A.; Tamae, K.; Ueshima, K.; Watanabe, H.; Xu, B. D.; Yamada, S.; Yamauchi, Y.; Yoshida, H.; Kozlov, A.; Takemoto, Y.; Yoshida, S.; Grant, C.; Keefer, G.; McKee, D. W.; Piepke, A.; Banks, T. I.; Bloxham, T.; Freedman, S. J.; Fujikawa, B. K.; Han, K.; Hsu, L.; Ichimura, K.; Murayama, H.; O'Donnell, T.; Steiner, H. M.; Winslow, L. A.; Dwyer, D.; Mauger, C.; McKeown, R. D.; Zhang, C.; Berger, B. E.; Lane, C. E.; Maricic, J.; Miletic, T.; Learned, J. G.; Sakai, M.; Horton-Smith, G. A.; Tang, A.; Downum, K. E.; Tolich, K.; Efremenko, Y.; Kamyshkov, Y.; Perevozchikov, O.; Karwowski, H. J.; Markoff, D. M.; Tornow, W.; Detwiler, J. A.; Enomoto, S.; Heeger, K.; Decowski, M. P.

2014-05-26T23:59:59.000Z

432

NOSTOS: a spherical TPC to detect low energy neutrinos  

E-Print Network (OSTI)

A novel low-energy ($\\sim$few keV) neutrino-oscillation experiment NOSTOS, combining a strong tritium source and a high pressure spherical Time Projection Chamber (TPC) detector 10 m in radius has been recently proposed. The oscillation of neutrinos of such energies occurs within the size of the detector itself, potentially allowing for a very precise (and rather systematics-free) measure of the oscillation parameters, in particular, of the smaller mixing angle $\\theta_{13}$, which value could be determined for the first time. This detector could also be sensitive to the neutrino magnetic moment and be capable of accurately measure the Weinberg angle at low energy. The same apparatus, filled with high pressure Xenon, exhibits a high sensitivity as a Super Nova neutrino detector with extra galactic sensitivity. The outstanding benefits of the new concept of the spherical TPC will be presented, as well as the issues to be demonstrated in the near future by an ongoing R&D. The very first results of small pro...

Aune, S; Dolbeau, J; Fanourakis, G K; Ferrer-Ribas, E; Geralis, T; Giomataris, Ioanis; Gorodetzky, P; Gounaris, George J; Irastorza, I G; Kousouris, K; Lepeltier, V; Patzak, T; Paschos, E A; Salin, P; Savvidis, I; Vergados, J D

2005-01-01T23:59:59.000Z

433

NOSTOS: a spherical TPC to detect low energy neutrinos  

SciTech Connect

A novel low-energy ({approx}few keV) neutrino-oscillation experiment NOSTOS, combining a strong tritium source and a high pressure spherical Time Projection Chamber (TPC) detector 10 m in radius has been recently proposed. The oscillation of neutrinos of such energies occurs within the size of the detector itself, potentially allowing for a very precise (and rather systematics-free) measure of the oscillation parameters, in particular, of the smaller mixing angle {theta}13, which value could be determined for the first time. This detector could also be sensitive to the neutrino magnetic moment and be capable of accurately measure the Weinberg angle at low energy. The same apparatus, filled with high pressure Xenon, exhibits a high sensitivity as a Super Nova neutrino detector with extra galactic sensitivity. The outstanding benefits of the new concept of the spherical TPC will be presented, as well as the issues to be demonstrated in the near future by an ongoing R and D. The very first results of small prototype in operation in Saclay are shown.

Aune, S.; Colas, P.; Ribas, E. Ferrer; Giomataris, Y.; Irastorza, I. G. [DAPNIA, Centre d'Etudes Nucleaires de Saclay (CEA-Saclay), Gif-sur-Yvette (France); Dolbeau, J.; Gorodetzky, P.; Patzak, T.; Salin, P. [APC, Universite Paris 7 Denis Diderot, Paris (France); Fanourakis, G.; Geralis, T.; Kousouris, K. [National Center for Scientific Research 'Demokritos', Athens (Greece); Gounaris, G. J.; Savvidis, I. [Aristotle University of Thessaloniki (Greece); Lepeltier, V. [Laboratoire de l'Accelerateur Lineaire, Orsay (France); Paschos, E.A. [University of Dortmunt, Dortmunt (Germany); Vergados, J.D. [University of Ioannina, Ioannina (Greece)

2005-09-08T23:59:59.000Z

434

Solar monopoles and terrestrial neutrinos  

SciTech Connect

Magnetic monopoles captured in the core of the sun may give rise to a substantial flux of energetic neutrinos by catalyzing the decay of solar hydrogen. We discuss the expected neutrino flux in underground detectors under different assumptions about solar interior conditions. Although a monopole flux as low as F/sub M/ /approximately/ 10/sup /minus/24/ cm/sup /minus/2/ sec/sup /minus/1/ sr/sup /minus/1/ could give rise to a neutrino flux above atmospheric background, due to M/bar M/ annihilation, this does not translate into a reliable monopole flux bound stronger than the Parker limit. 8 refs., 1 fig.

Frieman, J.

1988-04-01T23:59:59.000Z

435

Neutrino interactions in neutron matter  

E-Print Network (OSTI)

Neutrino flow is the dominant mechanism of energy transfer in the latest stages of supernovae explosions and in compact stars. The Standard Model of particle physics and accelerator data, provide a satisfactory description of neutrino physics in vacuum up to TeV scale. Nevertheless modeling the dynamics of neutrino interaction in the nuclear environment involves severe difficulties. This thesis in mainly aimed at obtaining the weak response of infinite matter, using both the Correlated Basis Function theory and Landau Theory of Fermi liquid to take into account properly nucleon-nucleon hard core potential and long range correlation (quasi-particle, collective modes, ecc.)

Cipollone, Andrea

2012-01-01T23:59:59.000Z

436

Neutrino interactions in neutron matter  

E-Print Network (OSTI)

Neutrino flow is the dominant mechanism of energy transfer in the latest stages of supernovae explosions and in compact stars. The Standard Model of particle physics and accelerator data, provide a satisfactory description of neutrino physics in vacuum up to TeV scale. Nevertheless modeling the dynamics of neutrino interaction in the nuclear environment involves severe difficulties. This thesis in mainly aimed at obtaining the weak response of infinite matter, using both the Correlated Basis Function theory and Landau Theory of Fermi liquid to take into account properly nucleon-nucleon hard core potential and long range correlation (quasi-particle, collective modes, ecc.)

Andrea Cipollone

2012-12-20T23:59:59.000Z

437

Limits on Sensitivity of Large Silicon Bolometers for Solar Neutrino Detection  

Science Journals Connector (OSTI)

...F.T., ULTRALOW-BACKGROUND STUDY OF NEUTRINOLESS DOUBLE BETA-DECAY OF GE-76 - NEW LIMIT ON THE MAJORANA MASS...FORSTER, A, LOW BACKGROUND STUDY OF THE NEUTRINOLESS DOUBLE BETA-DECAY OF 76-GE AND UPPER LIMIT FOR NEUTRINO MASS...

C. J. MARTOFF

1987-07-31T23:59:59.000Z

438

Evidence for neutrino oscillations in the Sudbury Neutrino Observatory  

SciTech Connect

The Sudbury Neutrino Observatory (SNO) is a large-volume heavy water Cerenkov detector designed to resolve the solar neutrino problem. SNO observes charged-current interactions with electron neutrinos, neutral-current interactions with all active neutrinos, and elastic-scattering interactions primarily with electron neutrinos with some sensitivity to other flavors. This dissertation presents an analysis of the solar neutrino flux observed in SNO in the second phase of operation, while {approx}2 tonnes of salt (NaCl) were dissolved in the heavy water. The dataset here represents 391 live days of data. Only the events above a visible energy threshold of 5.5 MeV and inside a fiducial volume within 550 cm of the center of the detector are studied. The neutrino flux observed via the charged-current interaction is [1.71 {+-} 0.065(stat.){+-}{sub 0.068}{sup 0.065}(sys.){+-}0.02(theor.)] x 10{sup 6}cm{sup -2}s{sup -1}, via the elastic-scattering interaction is [2.21{+-}0.22(stat.){+-}{sub 0.12}{sup 0.11}(sys.){+-}0.01(theor.)] x 10{sup 6}cm{sup -2}s{sup -1}, and via the neutral-current interaction is [5.05{+-}0.23(stat.){+-}{sub 0.37}{sup 0.31}(sys.){+-}0.06(theor.)] x 10{sup 6}cm{sup -2}s{sup -1}. The electron-only flux seen via the charged-current interaction is more than 7{sigma} below the total active flux seen via the neutral-current interaction, providing strong evidence that neutrinos are undergoing flavor transformation as they travel from the core of the Sun to the Earth. The most likely origin of the flavor transformation is matter-induced flavor oscillation.

Marino, Alysia Diane

2004-08-10T23:59:59.000Z

439

Neutrino oscillation studies and the neutrino cross section  

E-Print Network (OSTI)

The present uncertainties in the knowledge of the neutrino cross sections for E_nu \\sim 1 GeV, that is in the energy range most important for atmospheric and long baseline accelerator neutrinos, are large. These uncertainties do not play a significant role in the interpretation of existing data, however they could become a limiting factor in future studies that aim at a complete and accurate determination of the neutrino oscillation parameters. New data and theoretical understanding on nuclear effects and on the electromagnetic structure functions at low Q^2 and in the resonance production region are available, and can be valuable in reducing the present systematic uncertainties. The collaboration of physicists working in different subfields will be important to obtain the most from this available information. It is now also possible, with the facilities developed for long baseline beams, to produce high intensity and well controlled neutrino beams to measure the neutrino interaction properties with much better precision that what was done in the past. Several projects and ideas to fully exploit these possibilities are under active investigation. These topics have been the object of the first neutrino interaction (NUINT01) workshop.

Paolo Lipari

2002-07-14T23:59:59.000Z

440

Search for a Light Sterile Neutrino at Daya Bay  

E-Print Network (OSTI)

A search for light sterile neutrino mixing was performed with the first 217 days of data from the Daya Bay Reactor Antineutrino Experiment. The experiment's unique configuration of multiple baselines from six 2.9~GW$_{\\rm th}$ nuclear reactors to six antineutrino detectors deployed in two near (effective baselines 512~m and 561~m) and one far (1579~m) underground experimental halls makes it possible to test for oscillations to a fourth (sterile) neutrino in the $10^{\\rm -3}~{\\rm eV}^{2} < |\\Delta m_{41}^{2}| < 0.3~{\\rm eV}^{2}$ range. The relative spectral distortion due to electron antineutrino disappearance was found to be consistent with that of the three-flavor oscillation model. The derived limits on $\\sin^22\\theta_{14}$ cover the $10^{-3}~{\\rm eV}^{2} \\lesssim |\\Delta m^{2}_{41}| \\lesssim 0.1~{\\rm eV}^{2}$ region, which was largely unexplored.

F. P. An; A. B. Balantekin; H. R. Band; W. Beriguete; M. Bishai; S. Blyth; I. Butorov; G. F. Cao; J. Cao; Y. L. Chan; J. F. Chang; L. C. Chang; Y. Chang; C. Chasman; H. Chen; Q. Y. Chen; S. M. Chen; X. Chen; X. Chen; Y. X. Chen; Y. Chen; Y. P. Cheng; J. J. Cherwinka; M. C. Chu; J. P. Cummings; J. de Arcos; Z. Y. Deng; Y. Y. Ding; M. V. Diwan; E. Draeger; X. F. Du; D. A. Dwyer; W. R. Edwards; S. R. Ely; J. Y. Fu; L. Q. Ge; R. Gill; M. Gonchar; G. H. Gong; H. Gong; M. Grassi; W. Q. Gu; M. Y. Guan; X. H. Guo; R. W. Hackenburg; G. H. Han; S. Hans; M. He; K. M. Heeger; Y. K. Heng; P. Hinrichs; Y. K. Hor; Y. B. Hsiung; B. Z. Hu; L. M. Hu; L. J. Hu; T. Hu; W. Hu; E. C. Huang; H. Huang; X. T. Huang; P. Huber; G. Hussain; Z. Isvan; D. E. Jaffe; P. Jaffke; K. L. Jen; S. Jetter; X. P. Ji; X. L. Ji; H. J. Jiang; J. B. Jiao; R. A. Johnson; L. Kang; S. H. Kettell; M. Kramer; K. K. Kwan; M. W. Kwok; T. Kwok; W. C. Lai; K. Lau; L. Lebanowski; J. Lee; R. T. Lei; R. Leitner; A. Leung; J. K. C. Leung; C. A. Lewis; D. J. Li; F. Li; G. S. Li; Q. J. Li; W. D. Li; X. N. Li; X. Q. Li; Y. F. Li; Z. B. Li; H. Liang; C. J. Lin; G. L. Lin; P. Y. Lin; S. K. Lin; Y. C. Lin; J. J. Ling; J. M. Link; L. Littenberg; B. R. Littlejohn; D. W. Liu; H. Liu; J. L. Liu; J. C. Liu; S. S. Liu; Y. B. Liu; C. Lu; H. Q. Lu; K. B. Luk; Q. M. Ma; X. Y. Ma; X. B. Ma; Y. Q. Ma; K. T. McDonald; M. C. McFarlane; R. D. McKeown; Y. Meng; I. Mitchell; J. Monari Kebwaro; Y. Nakajima; J. Napolitano; D. Naumov; E. Naumova; I. Nemchenok; H. Y. Ngai; Z. Ning; J. P. Ochoa-Ricoux; A. Olshevski; S. Patton; V. Pec; J. C. Peng; L. E. Piilonen; L. Pinsky; C. S. J. Pun; F. Z. Qi; M. Qi; X. Qian; N. Raper; B. Ren; J. Ren; R. Rosero; B. Roskovec; X. C. Ruan; B. B. Shao; H. Steiner; G. X. Sun; J. L. Sun; Y. H. Tam; X. Tang; H. Themann; K. V. Tsang; R. H. M. Tsang; C. E. Tull; Y. C. Tung; B. Viren; V. Vorobel; C. H. Wang; L. S. Wang; L. Y. Wang; M. Wang; N. Y. Wang; R. G. Wang; W. Wang; W. W. Wang; X. Wang; Y. F. Wang; Z. Wang; Z. Wang; Z. M. Wang; D. M. Webber; H. Y. Wei; Y. D. Wei; L. J. Wen; K. Whisnant; C. G. White; L. Whitehead; T. Wise; H. L. H. Wong; S. C. F. Wong; E. Worcester; Q. Wu; D. M. Xia; J. K. Xia; X. Xia; Z. Z. Xing; J. Y. Xu; J. L. Xu; J. Xu; Y. Xu; T. Xue; J. Yan; C. C. Yang; L. Yang; M. S. Yang; M. T. Yang; M. Ye; M. Yeh; Y. S. Yeh; B. L. Young; G. Y. Yu; J. Y. Yu; Z. Y. Yu; S. L. Zang; B. Zeng; L. Zhan; C. Zhang; F. H. Zhang; J. W. Zhang; Q. M. Zhang; Q. Zhang; S. H. Zhang; Y. C. Zhang; Y. M. Zhang; Y. H. Zhang; Y. X. Zhang; Z. J. Zhang; Z. Y. Zhang; Z. P. Zhang; J. Zhao; Q. W. Zhao; Y. Zhao; Y. B. Zhao; L. Zheng; W. L. Zhong; L. Zhou; Z. Y. Zhou; H. L. Zhuang; J. H. Zou

2014-07-27T23:59:59.000Z

Note: This page contains sample records for the topic "neutrino mass mixing" from the National Library of EnergyBeta (NLEBeta).
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441

High-Energy Neutrino Astronomy  

E-Print Network (OSTI)

Kilometer-scale neutrino detectors such as IceCube are discovery instruments covering nuclear and particle physics, cosmology and astronomy. Examples of their multidisciplinary missions include the search for the particle nature of dark matter and for additional small dimensions of space. In the end, their conceptual design is very much anchored to the observational fact that Nature accelerates protons and photons to energies in excess of 10^{20} and 10^{13} eV, respectively. The cosmic ray connection sets the scale of cosmic neutrino fluxes. In this context, we discuss the first results of the completed AMANDA detector and the reach of its extension, IceCube. Similar experiments are under construction in the Mediterranean. Neutrino astronomy is also expanding in new directions with efforts to detect air showers, acoustic and radio signals initiated by neutrinos with energies similar to those of the highest energy cosmic rays.

F. Halzen

2005-01-26T23:59:59.000Z

442

zeller-neutrino08.ppt  

NLE Websites -- All DOE Office Websites (Extended Search)

K2K MiniBooNE,SciBooNE MINERvA Sam Zeller, Neutrino 08 6 New Measurements * near future: - MINERA (2009) * present: - K2K (1999 - 2004) - MiniBooNE (2002 - present) -...

443

Neutrino Cross-Section Experiments  

NLE Websites -- All DOE Office Websites (Extended Search)

N u F a c t 0 9 11th International Workshop on Neutrino Factories, Superbeams and Beta Beams July 20-25, 2009 - Illinois Institute of Technology - Chicago David Schmitz, Fermilab...

444

Neutrino Factories and Beta Beams  

E-Print Network (OSTI)

a Neutrino Factory Based on Muon Beams, Proc. 2001 ParticleMD. [19] C. Rubbia et al. , Beam Cooling with Ionisationthe required unstable ion beams has recently been suggested

Zisman, Michael S.

2006-01-01T23:59:59.000Z

445

Neutrino parameters and the $N_2$-dominated scenario of leptogenesis  

E-Print Network (OSTI)

We briefly review the main aspects of leptogenesis, describing both the unflavoured and the flavoured versions of the $N_2$-dominated scenario. A study of the success rates of both classes of models has been carried out. We comment on these results and discuss corrective effects to this simplest scenario. Focusing on the flavoured case, we consider the conditions required by strong thermal leptogenesis, where the final asymmetry is fully independent of the initial conditions. Barring strong cancellations in the seesaw formula and in the flavoured decay parameters, we show that strong thermal leptogenesis favours a lightest neutrino mass $m_1\\gtrsim10\\,\\mbox{meV}$ for normal ordering (NO) and $m_1\\gtrsim 3\\,\\mbox{meV}$ for inverted ordering (IO). Finally, we briefly comment on the power of absolute neutrino mass scale experiments to either support or severely corner strong thermal leptogenesis.

Michele Re Fiorentin; Sophie E. King

2014-05-09T23:59:59.000Z

446

Standard and non-standard primordial neutrinos  

E-Print Network (OSTI)

The standard cosmological model predicts the existence of a cosmic neutrino background with a present density of about 110 cm^{-3} per flavour, which affects big-bang nucleosynthesis, cosmic microwave background anisotropies, and the evolution of large scale structures. We report on a precision calculation of the cosmic neutrino background properties including the modification introduced by neutrino oscillations. The role of a possible neutrino-antineutrino asymmetry and the impact of non-standard neutrino-electron interactions on the relic neutrinos are also briefly discussed.

P. D. Serpico

2006-08-14T23:59:59.000Z

447

Coherence effects in neutrino oscillations  

Science Journals Connector (OSTI)

We study the effect of coherent and incoherent broadening on neutrino oscillations both in vacuum and in the presence of matter (the MSW effect). We show under very general assumptions that it is not possible to distinguish experimentally neutrinos produced in some region of space as wave packets from those produced in the same region of space as plane waves with the same energy distribution. 1995 The American Physical Society.

Ken Kiers; Shmuel Nussinov; Nathan Weiss

1996-01-01T23:59:59.000Z

448

E-Print Network 3.0 - antares neutrino telescope Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

oscillation parameters. Keywords: neutrino oscillations, ANTARES, neutrino telescope 1 Introduction It is now... energy neutrino telescopes, whose energy threshold is...

449

Constraining the violation of the equivalence principle with IceCube atmospheric neutrino data  

Science Journals Connector (OSTI)

The recent high-statistics high-energy atmospheric neutrino data collected by IceCube open a new window to probe new physics scenarios that are suppressed in lower-energy neutrino experiments. In this paper we analyze the IceCube atmospheric neutrino data to constrain the violation of equivalence principle (VEP) in the framework of three neutrinos with nonuniversal gravitational couplings. In this scenario the effect of the VEP on neutrino oscillation probabilities can be parametrized by two parameters, ??21??2??1 and ??31??3??1, where ?is denote the coupling of neutrino mass eigenstates to the gravitational field. By analyzing the latest muon-tracks data sets of IceCube-40 and IceCube-79, besides providing the two-dimensional allowed regions in the (???21,???31) plane, we obtain the upper limits |???21|<9.110?27 (at 90% C.L.), which improves the previous limit by ?4 orders of magnitude, and |???31|?610?27 (at 90% C.L.), which improves the current limit by ?1 order of magnitude. Also we discuss in detail and analytically the effect of the VEP on neutrino oscillation probabilities.

A. Esmaili; D.?R. Gratieri; M.?M. Guzzo; P.?C. de Holanda; O.?L.?G. Peres; G.?A. Valdiviesso

2014-06-11T23:59:59.000Z

450

Three-body force effect on neutrino emissivities of neutron stars within the framework of the Brueckner-Hartree-Fock approach  

E-Print Network (OSTI)

The three-body force (TBF) effect on the neutrino emissivity in neutron star matter and the total neutrino emissivity of neutron stars have been investigated within the framework of the Brueckner-Hartree-Fock approach by adopting the AV18 two-body interaction plus a microscopic TBF. The neutrino emissivity from the direct Urca process turns out to be much larger than that from the modified Urca process. Inclusion of the TBF reduces strongly the density thresholds of the direct Urca processes involving electrons and muons. The TBF effect on the total neutrino emissivity of neutron stars is shown to be negligibly weak for neutron stars with small masses. For neutron stars with large masses, the TBF effect becomes visible and inclusion of the TBF may enhance the total neutrino emissivity by about 50% for neutron stars with a given mass of $M=1.6M_{\\odot}$.

Yin, Peng

2013-01-01T23:59:59.000Z

451

High Energy Neutrino Telescopes  

E-Print Network (OSTI)

This paper presents a review of the history, motivation and current status of high energy neutrino telescopes. Many years after these detectors were first conceived, the operation of kilometer-cubed scale detectors is finally on the horizon at both the South Pole and in the Mediterranean Sea. These new detectors will perhaps provide us the first view of high energy astrophysical objects with a new messenger particle and provide us with our first real glimpse of the distant universe at energies above those accessible by gamma-ray instruments. Some of the topics that can be addressed by these new instruments include the origin of cosmic rays, the nature of dark matter, and the mechanisms at work in high energy astrophysical objects such as gamma-ray bursts, active galactic nuclei, pulsar wind nebula and supernova remnants.

Hoffman, K D

2008-01-01T23:59:59.000Z

452

High Energy Neutrino Telescopes  

E-Print Network (OSTI)

This paper presents a review of the history, motivation and current status of high energy neutrino telescopes. Many years after these detectors were first conceived, the operation of kilometer-cubed scale detectors is finally on the horizon at both the South Pole and in the Mediterranean Sea. These new detectors will perhaps provide us the first view of high energy astrophysical objects with a new messenger particle and provide us with our first real glimpse of the distant universe at energies above those accessible by gamma-ray instruments. Some of the topics that can be addressed by these new instruments include the origin of cosmic rays, the nature of dark matter, and the mechanisms at work in high energy astrophysical objects such as gamma-ray bursts, active galactic nuclei, pulsar wind nebula and supernova remnants.

K. D. Hoffman

2008-12-18T23:59:59.000Z

453

Violation of the Equivalence Principle in the light of the SNO and SK solar neutrino results  

E-Print Network (OSTI)

The SNO result on charged current deuteron disintegration, the SuperKamiokande 1258-day data on electron scattering, and other solar neutrino results are used to revisit the model of neutrino oscillations driven by a violation of the equivalence principle. We use a chisq minimization technique to examine oscillation between the nu(e) and another active neutrino, both massless, and find that within the Standard Solar Model the fit to the SNO and SuperKamiokande spectra are moderately good while a very good fit is obtained when the absolute normalizations of the 8B and hep neutrino fluxes are allowed to vary. The best fit prefers large, but not maximal, mixing, essentially no hep neutrinos, and a 40% reduction in the 8B neutrino flux. The fit to the total rates from the different experiments is not encouraging but when the rates and spectra are considerd together the situation is much improved. We remark on the expectations of the VEP model for the neutral current measurements at SNO.

Amitava Raychaudhuri; Arunansu Sil

2001-07-03T23:59:59.000Z

454

Neutrino Portal Dark Matter: From Dwarf Galaxies to IceCube  

E-Print Network (OSTI)

It has been suggested that the baseline scenario of collisionless cold dark matter over-predicts the numbers of satellite galaxies, as well as the dark matter (DM) densities in galactic centers. This apparent lack of structure at small scales can be accounted for if one postulates neutrino-DM and DM-DM interactions mediated by light O(MeV) force carriers. In this letter, we consider a simple, consistent model of neutrinophilic DM with these features where DM and a "secluded" SM-singlet neutrino species are charged under a new $U(1)$ gauge symmetry. An important ingredient of this model is that the secluded sector couples to the Standard Model fields only through neutrino mixing. We observe that the secluded and active neutrinos recouple, leading to a large relic secluded neutrino population. This relic population can prevent small-scale halos from collapsing, while at same time significantly modifying the optical depth of ultra-high-energy neutrinos recently observed at Icecube. We find that the bulk of the p...

Cherry, John F; Shoemaker, Ian M

2014-01-01T23:59:59.000Z

455

Independent Measurement of the Total Active B8 Solar Neutrino Flux Using an Array of He3 Proportional Counters at the Sudbury Neutrino Observatory  

Science Journals Connector (OSTI)

The Sudbury Neutrino Observatory (SNO) used an array of He3 proportional counters to measure the rate of neutral-current interactions in heavy water and precisely determined the total active (?x) B8 solar neutrino flux. This technique is independent of previous methods employed by SNO. The total flux is found to be 5.54-0.31+0.33(stat)-0.34+0.36(syst)106??cm-2?s-1, in agreement with previous measurements and standard solar models. A global analysis of solar and reactor neutrino results yields ?m2=7.59-0.21+0.1910-5??eV2 and ?=34.4-1.2+1.3 degrees. The uncertainty on the mixing angle has been reduced from SNOs previous results.

B. Aharmim et al. (SNO Collaboration)

2008-09-09T23:59:59.000Z

456

Exploring the Neutrinoless Double Beta Decay in the Inverted Neutrino Hierarchy with Bolometric Detectors  

E-Print Network (OSTI)

Neutrinoless double beta decay (0nubb) is one of the most sensitive probes for physics beyond the Standard Model, providing unique information on the nature of neutrinos. In this paper we review the status and outlook for bolometric 0nubb decay searches. We summarize recent advances in background suppression demonstrated using bolometers with simultaneous readout of heat and light signals. We simulate several configurations of a future CUORE-like bolometer array which would utilize these improvements and present the sensitivity reach of a hypothetical next-generation bolometric 0nubb experiment. We demonstrate that a bolometric experiment with the isotope mass of about 1 ton is capable of reaching the sensitivity to the effective Majorana neutrino mass (|mee|) of order 10-20 meV, thus completely exploring the so-called inverted neutrino mass hierarchy region. We highlight the main challenges and identify priorities for an R&D program addressing them.

D. R. Artusa; F. T. Avignone III; O. Azzolini; M. Balata; T. I. Banks; G. Bari; J. Beeman; F. Bellini; A. Bersani; M. Biassoni; C. Brofferio; C. Bucci; X. Z. Cai; A. Camacho; L. Canonica; X. G. Cao; S. Capelli; L. Carbone; L. Cardani; M. Carrettoni; N. Casali; D. Chiesa; N. Chott; M. Clemenza; C. Cosmelli; O. Cremonesi; R. J. Creswick; I. Dafinei; A. Dally; V. Datskov; A. De Biasi; M. M. Deninno; S. Di Domizio; M. L. di Vacri; L. Ejzak; D. Q. Fang; H. A. Farach; M. Faverzani; G. Fernandes; E. Ferri; F. Ferroni; E. Fiorini; M. A. Franceschi; S. J. Freedman; B. K. Fujikawa; A. Giachero; L. Gironi; A. Giuliani; J. Goett; P. Gorla; C. Gotti; T. D. Gutierrez; E. E. Haller; K. Han; K. M. Heeger; R. Hennings-Yeomans; H. Z. Huang; R. Kadel; K. Kazkaz; G. Keppel; Yu. G. Kolomensky; Y. L. Li; C. Ligi; X. Liu; Y. G. Ma; C. Maiano; M. Maino; M. Martinez; R. H. Maruyama; Y. Mei; N. Moggi; S. Morganti; T. Napolitano; S. Nisi; C. Nones; E. B. Norman; A. Nucciotti; T. O'Donnell; F. Orio; D. Orlandi; J. L. Ouellet; M. Pallavicini; V. Palmieri; L. Pattavina; M. Pavan; M. Pedretti; G. Pessina; V. Pettinacci; G. Piperno; C. Pira; S. Pirro; E. Previtali; V. Rampazzo; C. Rosenfeld; C. Rusconi; E. Sala; S. Sangiorgio; N. D. Scielzo; M. Sisti; A. R. Smith; L. Taffarello; M. Tenconi; F. Terranova; W. D. Tian; C. Tomei; S. Trentalange; G. Ventura; M. Vignati; B. S. Wang; H. W. Wang; L. Wielgus; J. Wilson; L. A. Winslow; T. Wise; A. Woodcraft; L. Zanotti; C. Zarra; B. X. Zhu; S. Zucchelli

2014-04-17T23:59:59.000Z

457

Neutrino oscillation signatures of oxygen-neon-magnesium supernovae  

E-Print Network (OSTI)

We discuss the flavor conversion of neutrinos from core collapse supernovae that have oxygen-neon-magnesium (ONeMg) cores. Using the numerically calculated evolution of the star up to 650 ms post bounce, we find that, for the normal mass hierarchy, the electron neutrino flux in a detector shows signatures of two typical features of an ONeMg-core supernova: a sharp step in the density profile at the base of the He shell and a faster shock wave propagation compared to iron core supernovae. Before the shock hits the density step (t ~ 150 ms), the survival probability of electron neutrinos is about 0.68, in contrast to values of 0.32 or less for an iron core supernova. The passage of the shock through the step and its subsequent propagation cause a decrease of the survival probability and a decrease of the amplitude of oscillations in the Earth, reflecting the transition to a more adiabatic propagation inside the star. These changes affect the lower energy neutrinos first; they are faster and more sizable for larger theta_13. They are unique of ONeMg-core supernovae, and give the possibility to test the speed of the shock wave. The time modulation of the Earth effect and its negative sign at the neutronization peak are the most robust signatures in a detector.

C. Lunardini; B. Mueller; H. -Th. Janka

2007-12-18T23:59:59.000Z

458

Search for dark matter from the Galactic halo with the IceCube Neutrino Telescope  

Science Journals Connector (OSTI)

Self-annihilating or decaying dark matter in the Galactic halo might produce high energy neutrinos detectable with neutrino telescopes. We have conducted a search for such a signal using 276days of data from the IceCube 22-string configuration detector acquired during 2007 and 2008. The effect of halo model choice in the extracted limit is reduced by performing a search that considers the outer halo region and not the Galactic Center. We constrain any large-scale neutrino anisotropy and are able to set a limit on the dark matter self-annihilation cross section of ??Av??10-22??cm3?s-1 for weakly interacting massive particle masses above 1TeV, assuming a monochromatic neutrino line spectrum.

R. Abbasi et al. (IceCube Collaboration)

2011-07-29T23:59:59.000Z

459

numix.dvi  

NLE Websites -- All DOE Office Websites (Extended Search)

Neutrino Neutrino mixing 1 1. NEUTRINO MASS, MIXING, AND OSCILLATIONS Updated May 2012 by K. Nakamura (Kavli IPMU (WPI), U. Tokyo, KEK) and S.T. Petcov (SISSA/INFN Trieste, Kavli IPMU (WPI), U. Tokyo, Bulgarian Academy of Sciences). The experiments with solar, atmospheric, reactor and accelerator neutrinos have provided compelling evidences for oscillations of neutrinos caused by nonzero neutrino masses and neutrino mixing. The data imply the existence of 3-neutrino mixing in vacuum. We review the theory of neutrino oscillations, the phenomenology of neutrino mixing, the problem of the nature - Dirac or Majorana, of massive neutrinos, the issue of CP violation in the lepton sector, and the current data on the neutrino masses and mixing parameters. The open questions and the main goals of future research in the field of neutrino mixing and oscillations are outlined. 1.1. Introduction:

460

Solar Neutrinos: Models, Observations, and New Opportunities  

E-Print Network (OSTI)

I discuss the development and resolution of the solar neutrino problem, as well as opportunities now open to us to extend our knowledge of main-sequence stellar evolution and neutrino astrophysics.

W. C. Haxton

2007-10-11T23:59:59.000Z