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Title: Which is the flavor of cosmic neutrinos seen by IceCube?
Author: A. Palladino, G. Pagliaroli, F.L. Villante, F. Vissani

We analyse the high-energy neutrino events observed by IceCube, aiming to probe the initial flavor of cosmic neutrinos. We study the track-to-shower ratio of the subset with energy above 60 TeV, where the signal is expected to dominate and show that different production mechanisms give rise to different predictions even accounting for the uncertainties due to neutrino oscillations. We include for the first time the passing muons observed by IceCube in the analysis. They corroborate the hypotheses that cosmic neutrinos have been seen and their flavour matches expectations.

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Neutrino 'flavour' flip confirmed

An important new discovery has been made in Japan about neutrinos.
These are the ghostly particles that flood the cosmos but which are extremely hard to detect and study.
Experiments have now established that one particular type, known as the muon "flavour", can flip to the electron type during flight.
The observation is noteworthy because it allows for the possibility that neutrinos and their anti-particle versions might behave differently.

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Title: News on Right Handed Neutrinos
Authors: Marco Drewes 

Neutrinos are the only particles in the Standard Model of particle physics that have only been observed with left handed chirality to date. If right handed neutrinos exist, they could be responsible for several phenomena that have no explanation within the Standard Model, including neutrino oscillations, the baryon asymmetry of the universe, dark matter and dark radiation. After a pedagogical introduction, we review recent progress in the phenomenology of right handed neutrinos. We in particular discuss the mass ranges suggested by hints for neutrino oscillation anomalies and dark radiation (eV), sterile neutrino dark matter scenarios (keV) and experimentally testable theories of baryogenesis (GeV to TeV). We summarise constraints from theoretical considerations, laboratory experiments, astrophysics and cosmology for each of these. 

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Title: New Light Species and the CMB
Authors: Christopher Brust, David E. Kaplan, Matthew T. Walters

We consider the effects of new light species on the Cosmic Microwave Background. In the massless limit, these effects can be parameterised in terms of a single number, the relativistic degrees of freedom. We perform a thorough survey of natural, minimal models containing new light species and numerically calculate the precise contribution of each of these models to this number in the framework of effective field theory. After reviewing the relevant details of early universe thermodynamics, we provide a map between the parameters of any particular theory and the predicted effective number of degrees of freedom. We then use this map to interpret the recent results from the Cosmic Microwave Background survey done by the Planck satellite. Using this data, we present new constraints on the parameter space of several models containing new light species. Future measurements of the Cosmic Microwave Background can be used with this map to further constrain the parameter space of all such models.

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Neutrino oscillation
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Title: Towards a very precise knowledge of theta13
Authors: A. B. Balantekin (Wisconsin U., Madison)

Recent experimental developments towards obtaining a very precise value of the third neutrino mixing angle, \theta_{13}, are summarised. Various implications of the measured value of this angle are briefly discussed.

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Title: Neutrino. History of a unique particle
Authors: S. M. Bilenky

Neutrinos are the only fundamental fermions which have no electric charges. Because of that neutrinos have no direct electromagnetic interaction and at relatively small energies they can take part only in weak processes with virtual W^{±} and Z^{0} bosons (like \beta-decay of nuclei, inverse \beta process \bar\nu_{e}+p\to e^{+}n, etc.). Neutrino masses are many orders of magnitude smaller than masses of charged leptons and quarks. These two circumstances make neutrinos unique, special particles. The history of the neutrino is very interesting, exciting and instructive. We try here to follow the main stages of the neutrino history starting from the Pauli proposal and finishing with the discovery and study of neutrino oscillations.

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Title: High Energy Neutrinos from Space
Authors: Thomas K. Gaisser

This paper reviews the status of the search for high-energy neutrinos from astrophysical sources. Results from large neutrino telescopes in water (Antares, Baikal) and ice (IceCube) are discussed as well as observations from the surface with Auger and from high altitude with ANITA. Comments on IceTop, the surface component of IceCube are also included.

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Title: Superluminal neutrino energy spectrum of OPERA and MINOS
Authors: Ernst Trojan

We analyse the velocity dependence on energy of superluminal neutrino recorded by the OPERA and MINOS collaborations and manage to approximate the energy spectrum by a power law E=p+Cp^a where parameters must be be taken in the range a=0.40-1.18 and C=1.5x10^{-5}--4.15x10^{-4} (momentum and energy are expressed in GeV). There is now possibility to recognise the energy spectrum at better accuracy within the errors of measurements.

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Title: Proposed Search for a Fourth Neutrino with a PBq Antineutrino Source
Authors: Michel Cribier, Maximilien Fechner, Thierry Lasserre, Alain Letourneau, David Lhuillier, Guillaume Mention, Davide Franco, Vasily Kornoukhov, Stefan Schoenert
(Version v2)

Several observed anomalies in neutrino oscillation data can be explained by a hypothetical fourth neutrino separated from the three standard neutrinos by a squared mass difference of a few eVČ. We show that this hypothesis can be tested with a PBq (ten kilocurie scale) 144Ce or 106Ru antineutrino beta-source deployed at the center of a large low background liquid scintillator detector. In particular, the compact size of such a source could yield an energy-dependent oscillating pattern in event spatial distribution that would unabiguously determine neutrino mass differences and mixing angles.

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Title: Probing the neutrino mass hierarchy with the rise time of a supernova burst
Authors: Sovan Chakraborty (II Inst. Theor. Phys., Hamburg University), Tobias Fischer (GSI & Tech. Univ. Darmstadt), Lorenz Hudepohl, Hans-Thomas Janka (MPA, Garching), Alessandro Mirizzi (II Inst. Theor. Phys., Hamburg University), Pasquale Dario Serpico (LAPTh, Annecy)

The rise time of a Galactic supernova (SN) \bar{nu}_e lightcurve, observable at a high-statistics experiment such as the Icecube Cherenkov detector, can provide a diagnostic tool for the neutrino mass hierarchy at "large" 1-3 leptonic mixing angle theta_{13}. Thanks to the interplay of matter suppression of collective effects at early postbounce times on one hand and the presence of the ordinary Mikheyev-Smirnov-Wolfenstein effect in the outer layers of the SN on the other hand, a sufficiently fast rise time and the lack of long accretion-enhancement of the early iron-core SN signal are indicative of an inverted mass hierarchy. We investigate results from an extensive set of stellar core-collapse simulations obtained with two different codes to explore the robustness of these features concerning differences of the progenitor structure, high-density equation of state, detailed treatment of neutrino-matter interactions, and dimensionality of the simulation. We find that the faster rise time for an inverted hierarchy as compared to normal hierarchy is predicted by all models, yielding a promising perspective for the detection of this signature from a future Galactic SN event.

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