9,042 research outputs found
Assessing the role of nuclear effects in the interpretation of the MiniBooNE low-energy anomaly
We study the impact of the effect of multinucleon interactions in the
reconstruction of the neutrino energy on the fit of the MiniBooNE data in terms
of neutrino oscillations. We obtain some improvement of the fit of the
MiniBooNE low-energy excess in the framework of two-neutrino oscillations and a
shift of the allowed region in the -- plane
towards smaller values of and larger values of
. However this effect is not enough to solve the problem of the
appearance-disappearance tension in the global fit of short-baseline neutrino
oscillation data.Comment: 14 pages; to be published in PR
The spanish influenza pandemic: a lesson from history 100 years after 1918
In Europe in 1918, influenza spread through Spain, France, Great Britain and Italy, causing havoc with military operations during the First World War. The influenza pandemic of 1918 killed more than 50 million people worldwide. In addition, its socioeconomic consequences were huge. "Spanish flu", as the infection was dubbed, hit different agegroups, displaying a so-called "W-trend", typically with two spikes in children and the elderly. However, healthy young adults were also affected. In order to avoid alarming the public, several local health authorities refused to reveal the numbers of people affected and deaths. Consequently, it was very difficult to assess the impact of the disease at the time. Although official communications issued by health authorities worldwide expressed certainty about the etiology of the infection, in laboratories it was not always possible to isolate the famous Pfeiffer's bacillus, which was, at that time, deemed to be the cause of influenza. The first official preventive actions were implemented in August 1918; these included the obligatory notification of suspected cases and the surveillance of communities such as day-schools, boarding schools and barracks. Identifying suspected cases through surveillance, and voluntary and/or mandatory quarantine or isolation, enabled the spread of Spanish flu to be curbed. At that time, these public health measures were the only effective weapons against the disease, as no vaccines or antivirals were available. Virological and bacteriological analysis of preserved samples from infected soldiers and other young people who died during the pandemic period is a major step toward a better understanding of this pandemic and of how to prepare for future pandemics
Contextual Realization of the Universal Quantum Cloning Machine and of the Universal-NOT gate by Quantum Injected Optical Parametric Amplification
A simultaneous, contextual experimental demonstration of the two processes of
cloning an input qubit and of flipping it into the orthogonal qubit is
reported. The adopted experimental apparatus, a Quantum-Injected Optical
Parametric Amplifier (QIOPA) is transformed simultaneously into a Universal
Optimal Quantum Cloning Machine (UOQCM) and into a Universal NOT
quantum-information gate. The two processes, indeed forbidden in their exact
form for fundamental quantum limitations, will be found to be universal and
optimal, i.e. the measured fidelity of both processes F<1 will be found close
to the limit values evaluated by quantum theory. A contextual theoretical and
experimental investigation of these processes, which may represent the basic
difference between the classical and the quantum worlds, can reveal in a
unifying manner the detailed structure of quantum information. It may also
enlighten the yet little explored interconnections of fundamental axiomatic
properties within the deep structure of quantum mechanics. PACS numbers:
03.67.-a, 03.65.Ta, 03.65.UdComment: 27 pages, 7 figure
Continuous variable cloning via network of parametric gates
We propose an experimental scheme for the cloning machine of continuous
quantum variables through a network of parametric amplifiers working as
input-output four-port gates.Comment: 4 pages, 2 figures. To appear on Phys. Rev. Let
Quasielastic electron- and neutrino-nucleus scattering in a continuum random phase approximation approach
We present a continuum random phase approximation approach to study electron-
and neutrino-nucleus scattering cross sections, in the kinematic region where
quasielastic scattering is the dominant process. We show the validity of the
formalism by confronting inclusive () cross sections with the available
data. We calculate flux-folded cross sections for charged-current quasielastic
antineutrino scattering off C and compare them with the MiniBooNE
cross-section measurements. We pay special emphasis to the contribution of
low-energy nuclear excitations in the signal of accelerator-based
neutrino-oscillation experiments.Comment: 5 pages, 5 figures. Contribution to the proceedings of the 16th
International Workshop on Neutrino Factories and Future Neutrino Beam
Facilities (NUFACT-2014
Nuclear response for the Skyrme effective interaction with zero-range tensor terms. III. Neutron matter and neutrino propagation
The formalism of the linear response for the Skyrme energy density functional
including tensor terms derived in articles [1,2] for nuclear matter is applied
here to the case of pure neutron matter. As in article [2] we present
analytical results for the response function in all channels, the Landau
parameters and the odd-power sum rules. Special emphasis is given to the
inverse energy weighted sum rule because it can be used to detect non physical
instabilities. Typical examples are discussed and numerical results shown.
Moreover, as a direct application, neutrino propagation in neutron matter is
investigated through its neutrino mean free path at zero temperature. This
quantity turns out to be very sensitive to the tensor terms of the Skyrme
energy density functional
Electron-neutrino scattering off nuclei from two different theoretical perspectives
We analyze charged-current electron-neutrino cross sections on Carbon. We
consider two different theoretical approaches, on one hand the Continuum Random
Phase Approximation (CRPA) which allows a description of giant resonances and
quasielastic excitations, on the other hand the RPA-based calculations which
are able to describe multinucleon emission and coherent and incoherent pion
production as well as quasielastic excitations. We compare the two approaches
in the genuine quasielastic channel, and find a satisfactory agreement between
them at large energies while at low energies the collective giant resonances
show up only in the CRPA approach. We also compare electron-neutrino cross
sections with the corresponding muon-neutrino ones in order to investigate the
impact of the different charged-lepton masses. Finally, restricting to the
RPA-based approach we compare the sum of quasielastic, multinucleon emission,
coherent and incoherent one-pion production cross sections (folded with the
electron-neutrino T2K flux) with the charged-current inclusive
electron-neutrino differential cross sections on Carbon measured by T2K. We
find a good agreement with the data. The multinucleon component is needed in
order to reproduce the T2K electron-neutrino inclusive cross sections
A note on the relationship between rational and trigonometric solutions of the WDVV equations
Legendre transformations provide a natural symmetry on the space of solutions to the WDVV equations, and more specifically, between different Frobenius manifolds. In this paper a twisted Legendre transformation is constructed between solutions which define the corresponding dual Frobenius manifolds. As an application it is shown that certain trigonometric and rational solutions of the WDVV equations are related by such a twisted Legendre transform
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