4,627 research outputs found
Unbinned test of time-dependent signals in real-time neutrino oscillation experiments
Real-time neutrino oscillation experiments such as Super-Kamiokande (SK), the
Sudbury Neutrino Observatory (SNO), the Kamioka Liquid scintillator
Anti-Neutrino Detector (KamLAND), and Borexino, can detect time variations of
the neutrino signal, provided that the statistics is sufficiently high. We
quantify this statement by means of a simple unbinned test, whose sensitivity
depends on the variance of the signal in the time domain, as well as on the
total number of signal and background events. The test allows a unified
discussion of the statistical uncertainties affecting current or future
measurements of eccentricity-induced variations and of day-night asymmetries
(in SK, SNO, and Borexino), as well as of reactor power variations (in
KamLAND).Comment: 17 pages, including 3 figure
Addendum to: Model-dependent and -independent implications of the first Sudbury Neutrino Observatory results
In the light of recent experimental and theoretical improvements, we review
our previous model-independent comparison [hep-ph/0106247] of the
Super-Kamiokande (SK) and Sudbury Neutrino Observatory (SNO) solar neutrino
event rates, including updated values for the ``equalized'' SK datum and for
the reference Standard Solar Model (SSM) B neutrino flux. We find that the
joint SK+SNO evidence for active neutrino flavor transitions is confirmed at
the level of 3.3 standard deviations, independently of possible transitions to
sterile states. Barring sterile neutrinos, we estimate the 3-sigma range for
the B neutrino flux (normalized to SSM) as f_B=0.96 +0.54-0.55.
Accordingly, the 3-sigma range for the energy-averaged nu_e survival
probability is found to be = 0.31 +0.55-0.16, independently of the
functional form of P_ee. An increase of the reference nu_e + d --> p + p + e
cross section by ~3%, as suggested by recent theoretical calculations, would
slightly shift the central values of f_B and of to ~1.00 and ~0.29,
respectively, and would strengthen the model-independent evidence for nu_e
transitions into active states at the level of ~3.6 sigma.Comment: 6 pages + 2 figures. Addendum to hep-ph/010624
Global analysis of three-flavor neutrino masses and mixings
We present a comprehensive phenomenological analysis of a vast amount of data
from neutrino flavor oscillation and non-oscillation searches, performed within
the standard scenario with three massive and mixed neutrinos, and with
particular attention to subleading effects. The detailed results discussed in
this review represent a state-of-the-art, accurate and up-to-date (as of August
2005) estimate of the three-neutrino mass-mixing parameters.Comment: Final version (including a new Appendix), to be published in
"Progress in Particle and Nuclear Physics". Higher-resolution pdf file and
eps figures can be download from http://www.ba.infn.it/~now2004/PPNP_review
Neutrino masses and mixings: Status of known and unknown parameters
Within the standard 3nu mass-mixing framework, we present an up-to-date
global analysis of neutrino oscillation data (as of January 2016), including
the latest available results from experiments with atmospheric neutrinos
(Super-Kamiokande and IceCube DeepCore), at accelerators (first T2K anti-nu and
NOvA nu runs in both appearance and disappearance mode), and at short-baseline
reactors (Daya Bay and RENO far/near spectral ratios), as well as a reanalysis
of older KamLAND data in the light of the "bump" feature recently observed in
reactor spectra. We discuss improved constraints on the five known oscillation
parameters (delta m^2, |Delta m^2|, sin^2theta_12, sin^2theta_13,
sin^2theta_23), and the status of the three remaining unknown parameters: the
mass hierarchy, the theta_23 octant, and the possible CP-violating phase delta.
With respect to previous global fits, we find that the reanalysis of KamLAND
data induces a slight decrease of both delta m^2 and sin^2theta_12, while the
latest accelerator and atmospheric data induce a slight increase of |Delta
m^2|. Concerning the unknown parameters, we confirm the previous intriguing
preference for negative values of sin(delta) [with best-fit values around
sin(delta) ~ -0.9], but we find no statistically significant indication about
the theta_23 octant or the mass hierarchy (normal or inverted). Assuming an
alternative (so-called LEM) analysis of NOvA data, some delta ranges can be
excluded at >3 sigma, and the normal mass hierarchy appears to be slightly
favored at 90% C.L. We also describe in detail the covariances of selected
pairs of oscillation parameters. Finally, we briefly discuss the implications
of the above results on the three non-oscillation observables sensitive to the
(unknown) absolute nu mass scale: the sum of nu masses, the effective nu_e
mass, and the effective Majorana mass.Comment: 15 pages, 9 figures, 2 tables. Invited contribution prepared for the
Nuclear Physics B Special Issue on "Neutrino Oscillations" celebrating the
Nobel Prize in Physics 201
Atmospheric, Solar, and CHOOZ neutrinos: a global three generation analysis
We perform a global three generation analysis of the current solar and
atmospheric evidence in favor of neutrino oscillations. We also include the
negative results coming from CHOOZ to constrain the nu_e mixing. We study the
zones of mass-mixing oscillations parameters compatible with all the data. It
is shown that almost pure nu_mu nu_tau oscillations are required to
explain the atmospheric neutrino anomaly and almost pure nu_1 nu_2
oscillations to account for the solar neutrino deficit.Comment: 4 pages, talk given at 36th Rencontres de Moriond: Electroweak
Interactions and Unified Theories, Les Arcs, France, 10-17 Mar 200
Neutrino mass and mixing parameters: A short review
We present a brief review of the current status of neutrino mass and mixing
parameters, based on a comprehensive phenomenological analysis of neutrino
oscillation and non-oscillation searches, within the standard three-neutrino
mixing framework.Comment: 11 pages, including 7 figures. Presented at the 40th Rencontres de
Moriond on Electroweak Interactions and Unified Theories, La Thuile, Aosta
Valley, Italy, 5-12 Mar 200
Status of three-neutrino oscillation parameters, circa 2013
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.Comment: Updated and revised version, accepted for publication in PRD. The
analysis includes the latest (March 2014) T2K disappearance data: all the
figures and the numerical results have been updated, and parts of the text
have been revised accordingl
Internal Power Recovery Systems for Cryogenic Cooling Plants: Secondary Compressor Development
Abstract Refrigeration systems consume a relevant amount of electrical power worldwide. For this reason, in the last decades, several energy saving techniques have been proposed to reduce the power demand of such plants. The present paper deals with the development of an innovative internal power recovery system for industrial cryogenic cooling plants. Such an innovative system consists in a Compressor-Expander Group (CEG) for internal power recovery. In particular, the paper is focused on the development of the CEG compressor, which has to pre-compress the refrigerant main flow before the fluid enters the main compressor. The machine has been re-designed, modifying a centrifugal compressor for automotive turbocharging. To verify the performance and suggest improvements, a numerical fluid dynamic model has been set up and the commercial Ansys-CFX software has been utilized to perform steady-state 3D simulations. Expected performance of the secondary compressor are presented and discussed in this paper
Molecular Approach to Cutaneous Squamous Cell Carcinoma: From Pathways to Therapy
Cutaneous squamous cell carcinoma (cSCC) represents the second most frequent skin cancer,recently showing a rapid increase in incidence worldwide, with around >1 million cases/year in theUnited States and 2500 deaths [1] [...]
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