5,230 research outputs found
disappearance at the SPL, T2K-I and the Neutrino Factory
We study the disappearance channel at T2K-phase I and the SPL and
analyse the achievable reduction of present uncertainties in and
. We analyse the impact of discrete ambiguities in
sign() and sign(). We show how the
disappearance channel at the Neutrino Factory is complementary to the
``golden'' and ``silver'' appearance channels and can be used to reduce the
eightfold-ambiguity problem in ().Comment: 2 pages, 3 epsfig; NUFACT'05, 21-26 June 2005, Frascat
Physics reach of -beams and -factories: the problem of degeneracies
We discuss the physics reach of -Beams and -Factories from a
theoretical perspective, having as a guideline the problem of degeneracies. The
presence of degenerate solutions in the measure of the neutrino oscillation
parameters and is, in fact, the main problem that have
to be addressed in planning future neutrino oscillation experiments. If
degeneracies are not (at least partially) solved, it will be almost impossible
to perform, at any future facility, precise measurements of
and/or . After a pedagogical introduction on why degenerate solutions
arise and how we can get rid of them, we analyze the physics reach of current
-beam and -factory configurations. The physics reach of the
"standard" \BB is severely affected by degeneracies while a better result can
be obtained by higher- setups. At the \NF the combination of Golden and
Silver channels can solve the eightfold degeneracy down to Comment: 5 pages, 6 epsfig; NUFACT'05, 21-26 June 2005, Frascat
Micro-orbits in a many-branes model and deviations from Newton's law
We consider a 5-dimensional model with geometry , with compactification radius . The Standard Model particles are
localized onto a brane located at y=0, with identical branes localized at
different points in the extra dimension. Objects located on our brane can orbit
around objects located on a brane at a distance , with an orbit and a
period significantly different from the standard Newtonian ones. We study the
kinematical properties of the orbits, finding that it is possible to
distinguish one motion from the other in a large region of the initial
conditions parameter space. This is a warm-up to study if a SM-like mass
distribution on one (or more) distant brane(s) may represent a possible dark
matter candidate. After using the same technique to the study of orbits of
objects lying on the same brane (), we apply this method to detect generic
deviations from the inverse-square Newton's law. We propose a possible
experimental setup to look for departures from Newtonian motion in the
micro-world, finding that an order of magnitude improvement on present bounds
can be attained at the 95% CL under reasonable assumptions.Comment: Two-column format (20 pages), 10 figures; minor corrections and some
added reference
Degeneracies at a beta-Beam and a Super-Beam Facility
The presence of degeneracies can considerably worsen the measure of the
neutrino oscillation parameters and . We study the
physics reach of a specific ``CERN'' setup, using a standard -Beam and
Super-Beam facility. These facilities have a similar sensitivity in both
parameters. Their combination does not provide any dramatic improvement as
expected due to their almost identical L/E ratio. We analyse if adding the
correspondent disappearance channels can help in reducing the effect of
degeneracies in the measure.Comment: 5 pages, 7 eps figure
Full QCD on APE100 Machines
We present the first tests and results from a study of QCD with two flavours
of dynamical Wilson fermions using the Hybrid Monte Carlo Algorithm (HMCA) on
APE100 machines.Comment: 23 pages, LaTeX, 13 PS figures not include
Invisible Z decay width bounds on active-sterile neutrino mixing in the (3+1) and (3+2) models
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.Comment: 10 pages, 5 figure
disappearance at the SPL, T2K-I, NOA and the Neutrino Factory
We study the measurement of the atmospheric neutrino oscillation parameters,
and , at the disappearance channel at
three conventional beam facilities, the SPL, T2K-phase I and NOA. These
two parameters have been shown to be of crucial importance in the measurement
of two of the unknowns of the PMNS mixing matrix, and the
leptonic CP-violating phase . In our analyis, the effect of the two
discrete ambiguities, and , is explicitly taken into account. We analyse also the
disappearance channel at the Neutrino Factory, and combine it with the
``golden'' and ``silver'' appearance
channels to study its impact on the measurement of and .
Eventually, we present the sensitivity of the four facilities to different
observables: , , maximal , the sign of the
atmospheric mass difference, , and the -octant,
.Comment: 40 pages using epsfig; bibliography modifie
Are the therapeutic strategies in anorexia of ageing effective on nutritional status? A systematic review with meta-analysis
BACKGROUND:
Anorexia of ageing (AA) may be considered as a risk factor for frailty and has an important impact on quality of life, morbidity and mortality.
METHODS:
A systematic review and a meta-analysis were performed to summarise the results from several trials on the effectiveness of treatments in AA, as associated with depression, sensory impairment of taste and smell, decreased appetite or early satiety, and disability. Eligible studies were required to report baseline and follow-up values, the mean change (â-change) from baseline, and/or the mean difference among intervention groups versus control group, concerning food intake (kcal/daily) and/or nutritional outcomes, such as body weight, body mass index, albumin and Mini Nutritional Assessment.
RESULTS:
The systematic review included 20 papers based on different therapeutic approaches concerning food intake and/or nutritional outcomes. The results of the meta-analysis indicate that the interventions for AA have an important impact on body weight [+1.59 kg; 95% confidence interval (CI) = 1.48-+1.71 kg; P < 0.001) and on energy intake (+56.09 kcal; 95% CI = -54.05 to +166.25 kcal; P = 0.32). Regarding secondary outcomes, it was not possible to meta-analyse the limited amount of data availab le.
CONCLUSIONS:
The different variants of AA need to be defined because diverse therapeutic approaches are available. A more precise definition of the functional impairments associated with AA may allow a more correct decision about the most appropriate therapy to be prescribed. Moreover, this may allow for a more effective performance of the different therapeutic approaches once they are better targeted to the different scenarios of AA
Untangling CP Violation and the Mass Hierarchy in Long Baseline Experiments
In the overlap region, for the normal and inverted hierarchies, of the
neutrino-antineutrino bi-probability space for appearance,
we derive a simple identity between the solutions in the (, ) plane for the different hierarchies. The
parameter sets the scale of the
appearance probabilities at the atmospheric eV whereas controls the amount of CP
violation in the lepton sector. The identity between the solutions is that the
difference in the values of for the two hierarchies equals twice
the value of divided by the {\it critical} value
of . We apply this identity to the two proposed
long baseline experiments, T2K and NOA, and we show how it can be used to
provide a simple understanding of when and why fake solutions are excluded when
two or more experiments are combined. The identity demonstrates the true
complimentarity of T2K and NOA.Comment: 15 pages, Latex, 4 postscript figures. Submitted to New Journal of
Physics, ``Focus on Neutrino Physics'' issu
New interactions: past and future experiments
In this talk I will review the present status and future perspectives of some
popular extensions of the conventional three-neutrino oscillation scenario,
from a purely phenomenological point of view. For concreteness I will focus
only on three specific scenarios: non-standard neutrino interactions with
matters, models with extra sterile neutrinos, and neutrino decay and
decoherence.Comment: LaTeX file using jpconf class, 8 pages, 2 tables. Proceedings of the
"XXIII International Conference on Neutrino Physics and Astrophysics"
(Neutrino 08), Christchurch, New Zealand, May 25-31, 200
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