We study the phenomenology of neutrino decay together with neutrino oscillations in the context of eV-scale sterile neutrinos. We review the formalism of visible neutrino decay in which one of the ...decay products is a neutrino that potentially can be observed. We apply the formalism developed for decay to the recent sterile neutrino search performed by IceCube with TeV neutrinos. We show that for a ν4 lifetime τ4/m4≲10−16 eV−1 s, the interpretation of the high-energy IceCube analysis can be significantly changed.
Recent global fits to short-baseline neutrino oscillation data have been performed finding preference for a sterile neutrino solution (3+1) over null. In the most recent iteration, it was pointed out ...that an unstable sterile neutrino (3+1+decay) may be a better description of the data. This is due to the fact that this model significantly reduces the tension between appearance and disappearance datasets. In this work, we add a 1-year IceCube dataset to the global fit obtaining new results for the standard 3+1 and 3+1+decay sterile neutrino scenarios. We find that the 3+1+decay model provides a better fit than the 3+1, even in the presence of IceCube, with reduced appearance to disappearance tension. The 3+1+decay model is a 5.4σ improvement over the null hypothesis and a 2.8σ improvement over the standard 3+1 model.
Actuellement les possibilités de valorisation énergétique de la biomasse par les procédés biotechnologiques représentent une solution de choix pour l’utilisation des produits agricoles de faible ...valeur commerciale, les liquides des industries agro-alimentaires, les résidus de récoltes…. La valorisation de cette biomasse, en particulier de nature organique, se fait par différents procédés biotechnologiques. La région d’Adrar produit annuellement un tonnage important de dattes, environ 675 mille quintaux par an (D.S.A, 2008). Les dattes dites communes présentent une faible valeur marchande par rapport à Deglet Nour, Degla Beida et Ghars. Elles sont destinées à l’autoconsommation, l’alimentation animale ou à l’échange sous forme de troc vers le Mali et le Niger. Cependant aucune industrie de transformation de la datte, n’est implantée dans la région. Aujourd’hui grâce aux procédés biotechnologiques, il est possible de valoriser les dattes communes de faible valeur marchande et de mettre sur le marché local et international, une nouvelle génération de produits à hautes valeurs ajoutées tel que le bioéthanol. Dans cette optique, de nombreux essais de fermentation alcoolique à l’échelle de laboratoire sont lancés afin de fixer les paramètres suivants: le taux de dilution, la quantité de levures (Saccharomyces cerevisiae) et le temps de fermentation afin d’optimiser le procédé. Nous avons comparé le degré d’alcool brut de quatre variétés de dattes communes (Hmira, Tinacer et Kaciene) pour 200 g de pulpes de dattes. Nous avons obtenu après l’étape de distillation, les résultats suivants pour les trois variétés considérées: 22°, 19° et 18°.
In neutrino experiments, hemispherical photomultiplier tubes (PMTs) are often used to cover large surfaces or volumes to maximize the photocathode coverage with a minimum number of channels. ...Instrumentation is often coarse, and neutrino event reconstruction and particle identification (PID) is usually done through the morphology of PMT hits. In future neutrino experiments, it may be desirable to perform PID from a few hits, or even a single hit, by utilizing pulse shape information. In this report, we study the principle of pulse shape PID using a single 25.4 cm hemispherical PMT in a spherical glass housing for future neutrino telescopes. We use the Fermilab Test Beam Facility (FTBF) MTest beam line to demonstrate that with pulse shape PID, it is possible to statistically separate 2 GeV electrons from 8 GeV pions, where the total charge deposition is ˜20 PE in our setup. Such techniques can be applied to future neutrino telescopes focusing on low-energy physics, including the IceCube-Upgrade.
quelle protection pour le fœtus? Moulai, M.; Belhassen, W.
Journal de pédiatrie et de puériculture,
2001, Letnik:
14, Številka:
6
Journal Article
Recenzirano
Le refus de soins de la part de la femme enceinte pour le bien de son fœtus souléve des questions tant éthiques que juridiques et invite à une réflexion sur l'engagement de la future mère à l'égard ...de l'enfant qu'elle porte, la protection de l'enfant à naître et notre responsabilité à l'égard du futur citoyen.
Recent global fits to short-baseline neutrino oscillation data have been performed finding preference for a sterile neutrino solution (3+1) over null. In the most recent iteration, it was pointed out ...that an unstable sterile neutrino (3+1+decay) may be a better description of the data. This is due to the fact that this model significantly reduces the tension between appearance and disappearance datasets. In this work, we add a one-year IceCube dataset to the global fit obtaining new results for the standard 3+1 and 3+1+decay sterile neutrino scenarios. We find that the 3+1+decay model provides a better fit than the 3+1, even in the presence of IceCube, with reduced appearance to disappearance tension. The 3+1+decay model is a 5.4\(\sigma\) improvement over the null hypothesis and a 2.8\(\sigma\) improvement over the standard 3+1 model.
In neutrino experiments, hemispherical photomultiplier tubes (PMTs) are often used to cover large surfaces or volumes to maximize the photocathode coverage with a minimum number of channels. ...Instrumentation is often coarse, and neutrino event reconstruction and particle identification (PID) is usually done through the morphology of PMT hits. In future neutrino experiments, it may be desirable to perform PID from a few hits, or even a single hit, by utilizing pulse shape information. In this report, we study the principle of pulse shape PID using a single 10-inch hemispherical PMT in a spherical glass housing for future neutrino telescopes. We use the Fermilab Test Beam Facility (FTBF) MTest beamline to demonstrate that with pulse shape PID, statistical separation is possible to distinguish 2 GeV electrons from 8 GeV pions, where the total charge deposition is ~20 PE in our setup. Such techniques can be applied to future neutrino telescopes focusing on low energy physics, including the IceCube-Upgrade.
MITPC is a gas-based time projection chamber used for detecting fast, MeV-scale neutrons. The standard version of the detector relies on a mixture of 600~torr gas composed of 87.5% \(^4\)He and 12.5% ...CF\(_4\) for precisely measuring the energy and direction of neutron-induced nuclear recoils. We describe studies performed with a prototype detector investigating the use of Ne, as a replacement for \(^4\)He, in the gas mixture. Our discussion focuses on the advantages of Ne as the fast neutron target for high energy neutron events (\(\lesssim\)100 MeV) and a demonstration that the mixture will be effective for this event class. We find that the achievable gain and transverse diffusion of drifting electrons in the Ne mixture are acceptable and that the detector uptime lost due to voltage breakdowns in the amplification plane is negligible, compared to \(\sim\) 20% with the \(^4\)He mixture.
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