4,877 research outputs found
Signals for strange quark contributions to the neutrino (antineutrino) scattering in quasi-elastic region
Strange quark contributions to the neutrino (antineutrino) scattering are
investigated on the elastic neutrino-nucleon scattering and the
neutrino-nucleus scattering for 12C target in the quasi-elastic region on the
incident energy of 500 MeV, within the framework of a relativistic single
particle model. For the neutrino-nucleus scattering, the effects of final state
interaction for the knocked-out nucleon are included by a relativistic optical
potential. In the cross sections we found some cancellations of the strange
quark contributions between the knocked-out protons and neutrons. Consequently,
the asymmetries between the incident neutrino and antineutrino which is the
ratio of neutral current to charged current, and the difference between the
asymmetries are shown to be able to yield more feasible quantities for the
strangeness effects. In order to explicitly display importance of the
cancellations, results of the exclusive reaction 16O(\nu, \nu' p) are
additionally presented for detecting the strangeness effects.Comment: 14 pages, 8 figures, submitted to Phys. Lett.
Neutrino tomography - Learning about the Earth's interior using the propagation of neutrinos
Because the propagation of neutrinos is affected by the presence of Earth
matter, it opens new possibilities to probe the Earth's interior. Different
approaches range from techniques based upon the interaction of high energy
(above TeV) neutrinos with Earth matter, to methods using the MSW effect on the
neutrino oscillations of low energy (MeV to GeV) neutrinos. In principle,
neutrinos from many different sources (sun, atmosphere, supernovae, beams etc.)
can be used. In this talk, we summarize and compare different approaches with
an emphasis on more recent developments. In addition, we point out other
geophysical aspects relevant for neutrino oscillations.Comment: 22 pages, 9 figures. Proceedings of ``Neutrino sciences 2005:
Neutrino geophysics'', December 14-16, 2005, Honolulu, USA. Minor changes,
some references added. Final version to appear in Earth, Moon, and Planet
Search for Neutrinoless Double-Beta Decay of Te with CUORE-0
We report the results of a search for neutrinoless double-beta decay in a
9.8~kgyr exposure of Te using a bolometric detector array,
CUORE-0. The characteristic detector energy resolution and background level in
the region of interest are FWHM and ~counts/(keVkgyr), respectively. The
median 90%~C.L. lower-limit sensitivity of the experiment is and surpasses the sensitivity of previous searches. We find
no evidence for neutrinoless double-beta decay of Te and place a
Bayesian lower bound on the decay half-life, ~ at 90%~C.L. Combining CUORE-0 data with the 19.75~kgyr
exposure of Te from the Cuoricino experiment we obtain at 90%~C.L.~(Bayesian), the most stringent
limit to date on this half-life. Using a range of nuclear matrix element
estimates we interpret this as a limit on the effective Majorana neutrino mass,
-- .Comment: 6 pages, 5 figures, updated version as published in PR
A Beta Beam complex based on the machine upgrades for the LHC
The Beta Beam CERN design is based on the present LHC injection complex and
its physics reach is mainly limited by the maximum rigidity of the SPS. In
fact, some of the scenarios for the machine upgrades of the LHC, particularly
the construction of a fast cycling 1 TeV injector (``Super-SPS''), are very
synergic with the construction of a higher Beta Beam. At the energies
that can be reached by this machine, we demonstrate that dense calorimeters can
already be used for the detection of at the far location. Even at
moderate masses (40 kton) as the ones imposed by the use of existing
underground halls at Gran Sasso, the CP reach is very large for any value of
that would provide evidence of appearance at T2K or
NOA (). Exploitation of matter effects at the
CERN to Gran Sasso distance provides sensitivity to the neutrino mass hierarchy
in significant areas of the plane
Exploring the Neutrinoless Double Beta Decay in the Inverted Neutrino Hierarchy with Bolometric Detectors
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.Comment: 22 pages, 15 figures, submitted to EPJ
The Complementarity of Eastern and Western Hemisphere Long-Baseline Neutrino Oscillation Experiments
We present a general formalism for extracting information on the fundamental
parameters associated with neutrino masses and mixings from two or more long
baseline neutrino oscillation experiments. This formalism is then applied to
the current most likely experiments using neutrino beams from the Japan Hadron
Facility (JHF) and Fermilab's NuMI beamline. Different combinations of muon
neutrino or muon anti-neutrino running are considered. To extract the type of
neutrino mass hierarchy we make use of the matter effect. Contrary to naive
expectation, we find that both beams using neutrinos is more suitable for
determining the hierarchy provided that the neutrino energy divided by baseline
() for NuMI is smaller than or equal to that of JHF. Whereas to determine
the small mixing angle, , and the CP or T violating phase
, one neutrino and the other anti-neutrino is most suitable. We make
extensive use of bi-probability diagrams for both understanding and extracting
the physics involved in such comparisons.Comment: 21 pages, Latex, 3 postscript figure
Analysis Techniques for the Evaluation of the Neutrinoless Double-Beta Decay Lifetime in Te with CUORE-0
We describe in detail the methods used to obtain the lower bound on the
lifetime of neutrinoless double-beta () decay in Te and
the associated limit on the effective Majorana mass of the neutrino using the
CUORE-0 detector. CUORE-0 is a bolometric detector array located at the
Laboratori Nazionali del Gran Sasso that was designed to validate the
background reduction techniques developed for CUORE, a next-generation
experiment scheduled to come online in 2016. CUORE-0 is also a competitive
decay search in its own right and functions as a platform to
further develop the analysis tools and procedures to be used in CUORE. These
include data collection, event selection and processing, as well as an
evaluation of signal efficiency. In particular, we describe the amplitude
evaluation, thermal gain stabilization, energy calibration methods, and the
analysis event selection used to create our final decay search
spectrum. We define our high level analysis procedures, with emphasis on the
new insights gained and challenges encountered. We outline in detail our
fitting methods near the hypothesized decay peak and catalog
the main sources of systematic uncertainty. Finally, we derive the
decay half-life limits previously reported for CUORE-0,
yr, and in combination with the Cuoricino
limit, yr.Comment: 18 pages, 18 figures. (Version 3 reflects only minor changes to the
text. Few additional details, no major content changes.
The low energy spectrum of TeO2 bolometers: results and dark matter perspectives for the CUORE-0 and CUORE experiments
We collected 19.4 days of data from four 750 g TeO2 bolometers, and in three
of them we were able to set the energy threshold around 3 keV using a new
analysis technique. We found a background rate ranging from 25 cpd/keV/kg at 3
keV to 2 cpd/keV/kg at 25 keV, and a peak at 4.7 keV. The origin of this peak
is presently unknown, but its presence is confirmed by a reanalysis of 62.7
kg.days of data from the finished CUORICINO experiment. Finally, we report the
expected sensitivities of the CUORE0 (52 bolometers) and CUORE (988 bolometers)
experiments to a WIMP annual modulation signal.Comment: 9 pages, 10 figure
Search for 14.4 keV solar axions from M1 transition of Fe-57 with CUORE crystals
We report the results of a search for axions from the 14.4 keV M1 transition
from Fe-57 in the core of the sun using the axio-electric effect in TeO2
bolometers. The detectors are 5x5x5 cm3 crystals operated at about 10 mK in a
facility used to test bolometers for the CUORE experiment at the Laboratori
Nazionali del Gran Sasso in Italy. An analysis of 43.65 kg d of data was made
using a newly developed low energy trigger which was optimized to reduce the
detectors energy threshold. An upper limit of 0.63 c kg-1 d-1 was established
at 95% C.L.. From this value, a lower bound at 95% C.L. was placed on the
Peccei-Quinn energy scale of fa >= 0.76 10**6 GeV for a value of S=0.55 for the
flavor-singlet axial vector matrix element. Bounds are given for the interval
0.15 < S < 0.55.Comment: 14 pages, 6 figures, submitted to JCA
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