11 research outputs found
Global analysis of neutrino oscillation data in four-neutrino schemes
We present an analysis of the global neutrino oscillation data in terms of four-neutrino mass schemes. We find that the strong preference of oscillations into active neutrinos implied by the latest solar as well as atmospheric neutrino data allows to rule out (2+2) mass schemes, whereas (3+1) schemes are strongly disfavoured by short-baseline experiments. Our analysis shows that four-neutrino oscillations do not provide a satisfactory description of the global neutrino oscillation data including the LSND result
Constraining Majorana neutrino electromagnetic properties from the LMA-MSW solution of the solar neutrino problem
In this paper we use solar neutrino data to derive stringent bounds on
Majorana neutrino transition moments (TMs). Should such be present, they would
contribute to the neutrino--electron scattering cross section and hence alter
the signal observed in Super-Kamiokande. Motivated by the growing robustness of
the LMA-MSW solution of the solar neutrino problem indicated by recent data,
and also by the prospects of its possible confirmation at KamLAND, we assume
the validity of this solution, and we constrain neutrino TMs by using the
latest global solar neutrino data. We find that all elements of the TM matrix
can be bounded at the same time. Furthermore, we show how reactor data play a
complementary role to the solar neutrino data, and use the combination of both
data sets to improve the current bounds. Performing a simultaneous fit of
LMA-MSW oscillation parameters and TMs we find that 6.3 times 10^{-10} mu_B and
2.0 times 10^{-10} mu_B are the 90% C.L. bounds from solar and combined solar +
reactor data, respectively. Finally, we perform a simulation of the upcoming
Borexino experiment and show that it will improve the bounds from today's data
by roughly one order of magnitude.Comment: Latex, 24 pages, 6 figures; misprints correcte
Ruling out four-neutrino oscillation interpretations of the LSND anomaly?
Prompted by recent solar and atmospheric data, we re-analyze the
four-neutrino description of current global neutrino oscillation data,
including the LSND evidence for oscillations. The higher degree of rejection
for non-active solar and atmospheric oscillation solutions implied by the SNO
neutral current result as well as by the latest 1489-day Super-K atmospheric
neutrino data allows us to rule out (2+2) oscillation schemes proposed to
reconcile LSND with the rest of current neutrino oscillation data. Using an
improved goodness of fit (gof) method especially sensitive to the combination
of data sets we obtain a gof of only 1.6 times 10^{-6} for (2+2) schemes.
Further, we re-evaluate the status of (3+1) oscillations using two different
analyses of the LSND data sample. We find that also (3+1) schemes are strongly
disfavoured by the data. Depending on the LSND analysis we obtain a gof of 5.6
times 10^{-3} or 7.6 times 10^{-5}. This leads to the conclusion that all
four-neutrino descriptions of the LSND anomaly, both in (2+2) as well as (3+1)
realizations, are highly disfavoured. Our analysis brings the LSND hint to a
more puzzling status.Comment: 21 pages, 7 figure
Status of a hybrid three-neutrino interpretation of neutrino data
We reanalyze the non-standard interaction (NSI) solutions to the solar
neutrino problem in the light of the latest solar, atmospheric and reactor
neutrino data. We show that such solutions, although preferred by the solar
data and consistent with the oscillation description of the atmospheric
neutrino data, are ruled out by the first results of the KamLAND reactor
experiment, at more than 3_sigma.Comment: 19 pages, LaTeX file using Elsart, 2 tables and 4 figures included.
This version updates the one published in Nucl.Phys.B629:479-490,2002 by
including the new KamLAND dat
New hadrons as ultra-high energy cosmic rays
Ultra-high energy cosmic ray (UHECR) protons produced by uniformly
distributed astrophysical sources contradict the energy spectrum measured by
both the AGASA and HiRes experiments, assuming the small scale clustering of
UHECR observed by AGASA is caused by point-like sources. In that case, the
small number of sources leads to a sharp exponential cutoff at the energy
E<10^{20} eV in the UHECR spectrum. New hadrons with mass 1.5-3 GeV can solve
this cutoff problem. For the first time we discuss the production of such
hadrons in proton collisions with infrared/optical photons in astrophysical
sources. This production mechanism, in contrast to proton-proton collisions,
requires the acceleration of protons only to energies E<10^{21} eV. The diffuse
gamma-ray and neutrino fluxes in this model obey all existing experimental
limits. We predict large UHE neutrino fluxes well above the sensitivity of the
next generation of high-energy neutrino experiments. As an example we study
hadrons containing a light bottom squark. These models can be tested by
accelerator experiments, UHECR observatories and neutrino telescopes.Comment: 17 pages, revtex style; v2: shortened, as to appear in PR
Quantum gravity phenomenology at the dawn of the multi-messenger era—A review
The exploration of the universe has recently entered a new era thanks to the multi-messenger paradigm, characterized by a continuous increase in the quantity and quality of experimental data that is obtained by the detection of the various cosmic messengers (photons, neutrinos, cosmic rays and gravitational waves) from numerous origins. They give us information about their sources in the universe and the properties of the intergalactic medium. Moreover, multi-messenger astronomy opens up the possibility to search for phenomenological signatures of quantum gravity. On the one hand, the most energetic events allow us to test our physical theories at energy regimes which are not directly accessible in accelerators; on the other hand, tiny effects in the propagation of very high energy particles could be amplified by cosmological distances. After decades of merely theoretical investigations, the possibility of obtaining phenomenological indications of Planck-scale effects is a revolutionary step in the quest for a quantum theory of gravity, but it requires cooperation between different communities of physicists (both theoretical and experimental). This review, prepared within the COST Action CA18108 “Quantum gravity phenomenology in the multi-messenger approach”, is aimed at promoting this cooperation by giving a state-of-the art account of the interdisciplinary expertise that is needed in the effective search of quantum gravity footprints in the production, propagation and detection of cosmic messengers.publishedVersio
Quantum gravity phenomenology at the dawn of the multi-messenger era—A review
The exploration of the universe has recently entered a new era thanks to the multi-messenger paradigm, characterized by a continuous increase in the quantity and quality of experimental data that is obtained by the detection of the various cosmic messengers (photons, neutrinos, cosmic rays and gravitational waves) from numerous origins. They give us information about their sources in the universe and the properties of the intergalactic medium. Moreover, multi-messenger astronomy opens up the possibility to search for phenomenological signatures of quantum gravity. On the one hand, the most energetic events allow us to test our physical theories at energy regimes which are not directly accessible in accelerators; on the other hand, tiny effects in the propagation of very high energy particles could be amplified by cosmological distances. After decades of merely theoretical investigations, the possibility of obtaining phenomenological indications of Planck-scale effects is a revolutionary step in the quest for a quantum theory of gravity, but it requires cooperation between different communities of physicists (both theoretical and experimental). This review, prepared within the COST Action CA18108 “Quantum gravity phenomenology in the multi-messenger approach”, is aimed at promoting this cooperation by giving a state-of-the art account of the interdisciplinary expertise that is needed in the effective search of quantum gravity footprints in the production, propagation and detection of cosmic messengers
Supernova neutrino burst detection with the deep underground neutrino experiment: DUNE Collaboration
The deep underground neutrino experiment (DUNE), a 40-kton underground liquid argon time projection chamber experiment, will be sensitive to the electron-neutrino flavor component of the burst of neutrinos expected from the next Galactic core-collapse supernova. Such an observation will bring unique insight into the astrophysics of core collapse as well as into the properties of neutrinos. The general capabilities of DUNE for neutrino detection in the relevant few- to few-tens-of-MeV neutrino energy range will be described. As an example, DUNE’s ability to constrain the νe spectral parameters of the neutrino burst will be considered. © 2021, The Author(s)
The DUNE Far Detector Interim Design Report, Volume 2: Single-Phase Module
The DUNE IDR describes the proposed physics program and technical designs of the DUNE far detector modules in preparation for the full TDR to be published in 2019. It is intended as an intermediate milestone on the path to a full TDR, justifying the technical choices that flow down from the high-level physics goals through requirements at all levels of the Project. These design choices will enable the DUNE experiment to make the ground-breaking discoveries that will help to answer fundamental physics questions. Volume 2 describes the single-phase module's subsystems, the technical coordination required for its design, construction, installation, and integration, and its organizational structure
The DUNE Far Detector Interim Design Report Volume 1: Physics, Technology and Strategies
The DUNE IDR describes the proposed physics program and technical designs of the DUNE Far Detector modules in preparation for the full TDR to be published in 2019. It is intended as an intermediate milestone on the path to a full TDR, justifying the technical choices that flow down from the high-level physics goals through requirements at all levels of the Project. These design choices will enable the DUNE experiment to make the ground-breaking discoveries that will help to answer fundamental physics questions. Volume 1 contains an executive summary that describes the general aims of this document. The remainder of this first volume provides a more detailed description of the DUNE physics program that drives the choice of detector technologies. It also includes concise outlines of two overarching systems that have not yet evolved to consortium structures: computing and calibration. Volumes 2 and 3 of this IDR describe, for the single-phase and dual-phase technologies, respectively, each detector module's subsystems, the technical coordination required for its design, construction, installation, and integration, and its organizational structure