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This paper gives an overview of the work done so far to produce sufficient neutrino fluxes for neutrino oscillation physics using beta beams. The design study on a beta beam scenario, the EURISOL (European Isotope Separation On-Line Radioactive Ion Beam Facility) Design Study, a project funded by the European Commission (EC), is now ready to be published. The study is based on the acceleration of 6He and 18Ne ions to produce the (anti-)neutrino beam using the existing CERN infrastructure for acceleration of the ions. We will here briefly describe the work with emphasis on how potential showstoppers, in particular radiation safety and equipment damage, have been dealt with. New results for the production of 6He show very encouraging results. We are now confident that this ion is a good choice to produce antineutrinos. However, the ion production needed for the physics experiments could not, up to now, be reasonably satisfied for 18Ne. Therefore, studies of alternative beta emitters, 8Li and 8B, with properties interesting for physics reach, have been proposed. The production of these ions is studied within the EC funded EUROnu project, “A High Intensity Neutrino Oscillation Facility for Europe.” This project will end in 2012. A small storage ring, in which the beam traverses a target, creating the 8Li and 8B isotopes that will be collected and accelerated, is studied in this proposal. We present the latest developments for the production of these ions, including a production ring lattice. Extensive Geant4 simulations have been done with the aim of developing a model of the production target that can be used for simulations of the necessary cooling system. In this paper we present the status of the work performed and an overview of ongoing and planned activities to make the beta beam project a solid proposal for neutrino production within the EUROnu project. [ABSTRACT FROM AUTHOR]

The neutrino oscillation data are well explained by the tri-bimaximal pattern. Recently a paper appeared showing that also the bimaximal pattern could be a very good starting point in order to describe the lepton mixing. In this paper I review both the flavour structures and then I present an explicit model. [ABSTRACT FROM AUTHOR]

Recent comparisons of independent and unrelated nuclear decay experiments have shown unexplained oscillations that appear to be common in frequency and phase. The most logical explanation for this fluctuation would be some common systematic or environmental factor. In this paper we provide detailed spectral analysis comparisons of several environmental factors with nuclear decay data from an experiment performed at the Brookhaven National Laboratory. We demonstrate that, although none of the environmental factors investigated can be causal, comparisons with ACRIM solar irradiance measurements provide good agreement with the nuclear decay data. This analysis provides the first direct evidence that the cause of the fluctuations has a possible solar origin. [ABSTRACT FROM AUTHOR]

In the baseline Neutrino Factory muon front end, strong, closely spaced solenoid magnets are used to contain the high emittance muon beam. In addition, significant acceleration is required for bunching, phase rotation and cooling, requiring RF cavities operating near to their maximum achievable gradient. There are experimental indications that RF cavities may not be able to achieve these large gradients in the presence of such intense magnetic fields. In this paper, I discuss the design of a muon cooling channel that is designed with RF cavities removed from the intense magnetic fields, and examine the change in performance that results from this compromise. [ABSTRACT FROM AUTHOR]

There has been a surge of progress and published results in neutrino cross-section physics in recent years. In many cases, absolute differential cross-sections are being measured for the first time and can be compared to interaction models first developed decades ago. These measurements are important input for the next generation of accelerator-based neutrino oscillation experiments where precise understanding of both signal and background channels will be critical to the observation of sub-dominant oscillation effects. This paper discusses recent results from several experiments and describes new experiments currently under construction dedicated to making these measurements with unprecedented precision. [ABSTRACT FROM AUTHOR]

OPERA is a long baseline neutrino oscillation experiment built to provide the final and unambiguous proof of the neutrino oscillation hypothesis in the atmospheric sector by observing ντ emerging from the CNGS νμ beam. The detector is a hybrid apparatus installed in the Hall C of the underground Gran Sasso National Laboratory in Italy. Runs with CNGS neutrinos were successfully carried out in 2007 and 2008. In this paper the detector and the analysis strategy are briefly described and the status of the analysis of the 2008 run events is discussed. [ABSTRACT FROM AUTHOR]

Super-Kamiokande is the world’s largest water Cherenkov detector, with a net mass of 50,000 tons. The scientific goals of the experiment include searches for proton decays, and studies of neutrinos from various sources. In this paper we review some of the latest results from our neutrino oscillations studies using atmospheric neutrinos, solar neutrinos and neutrinos from the KEK neutrino beam. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

Long-baseline experiments will play a crucial role in the precision era of neutrino oscillation physics. In this paper we review the ongoing European programme, which is focused on CNGS, and we discuss the opportunities for new facilities based on the CERN acceleration complex. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

We report first off-axis experimental electron neutrino (νe) and muon neutrino (νμ) results from T2K experiment based on 1.43×1020 proton-on-target beam data. Six νe candidate events are observed after applying selection cuts, indicating νμ → νe oscillation driven by non-zero θ13 at 2.5 σ significance. New result from νμ disappearance analysis will also be shown in this paper. [ABSTRACT FROM AUTHOR]

The propagation of radio emission in pulsar magnetospheres is discussed. We follow a kinematic model in order to derive dispersion relations for electromagnetic oscillations and transversal waves, propagating in a cold moving plasma. We have included relativistic corrections on the dispersion properties, involved with the relativistic motion of the emitting plasma. The occurrence of plasma instabilities is analyzed beside the conditions which should be fulfilled in order to permit the wave propagation and conversion in regions close to the cutoffs of the system. The existence of various frequencies of resonance has been predicted and we are working out these results in order to explain the low-frequency cutoffs observed in radio pulsar espectra. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

The Neutrino Factory is under intensive study in the framework of the International Design Study for future precision neutrino oscillation physics. According to the current baseline the major part of muon acceleration is foreseen to take part in the non-scaling fixed field alternating gradient (NS-FFAG) ring. The NS-FFAG lattice design was recently modified to accommodate long straight sections necessary for the injection/extraction systems. The length of the long drift was optimized minimizing the necessary septum field, which according to present studies needs to be below 2 T. The injection/extraction schemes allowing to reuse the kickers for both signs of muons are presented. The design of the kicker system based on current technology is discussed. The preliminary design of a septum magnet focused on minimization of the stray field leakage is studied. [ABSTRACT FROM AUTHOR]

While the neutrino oscillation experiments have measured non-zero square mass differences between neutrino flavors, the double beta decay is the most sensitive process to the absolute mass of the neutrinos and the only that can distinguish whether neutrino is a Dirac or a Majorana particle. These are a few but not the only reasons that many efforts, both theoretically and experimentally, are dedicated to the study of this process. In this lecture I'll give a short introduction to the double beta decay process. Different decay modes and mechanisms, a short history, decay rates and extraction of the neutrino mass parameter are presented. [ABSTRACT FROM AUTHOR]

We consider a dense neutrino gas as a many body system by taking into account both vacuum oscillations and self interactions of neutrinos. We show that the exact many body Hamiltonian which describes the flavor oscillations of such a dense neutrino gas has many constants of motion whose eigenvalues represent a set of good quantum numbers. However, if one adopts the random phase approximation as an effective one particle description, these operators are no longer conserved (i.e. they cease to represent good quantum numbers) although their expectation values are still conserved. [ABSTRACT FROM AUTHOR]

We discuss precision measurements of the leading atmospheric parameters at a standard neutrino factory. The oscillation of the muon and electron neutrinos (anti-neutrinos) to tau neutrinos (anti-neutrinos) adds to the muon events sample (both right sign and wrong sign) via leptonic decays of the taus produced through charge current interactions in the detector. We focus on how this contribution affects a precision measurement of the atmospheric mixing parameters and the deviation of νμ↔ντmixing from maximality. [ABSTRACT FROM AUTHOR]

Recent experiments on the breakdown of rf cavities revealed severe surface damage and a reduction of the maximum accelerating gradient after operation in an external magnetic field. This finding implies the possibility of serious problems for cooling lattices wherein rf cavities and external magnetic fields coexist, such as those of the proposed neutrino factory and muon collider. An experimental program that could study those problems and their possible solutions is discussed. Emphasis is given to a magnetically insulated cavity design in which the walls are parallel to the magnetic field lines and consequently damage from field emission is expected to be suppressed. [ABSTRACT FROM AUTHOR]

A channel for 6D ionization cooling of muons is described which consists of periodically inclined solenoids of alternating polarity, liquid hydrogen absorbers placed inside the solenoids and RF cavities between them. An important feature of such a channel (called Helical FOFO snake) is that it can cool simultaneously muons of both signs. Theoretical considerations as well as results of simulations with G4beamline are presented which show that a 200 MHz HFOFO snake has sufficient acceptance to be used for initial 6D cooling in muon colliders and neutrino factories. [ABSTRACT FROM AUTHOR]

We discuss a possible implementation of high-pressure gas-filled RF (HPRF) cavities in a linear cooling channel for muons and some of the technical issues that must be dealt with. The approach we describe is a hybrid approach that uses high-pressure hydrogen gas to avoid cavity breakdown, along with discrete LiH absorbers to provide the majority of the energy loss. Initial simulations show that the channel performs as well as the original vacuum RF channel while potentially avoiding the degradation in RF gradient associated with the strong magnetic field in the cooling channel. [ABSTRACT FROM AUTHOR]

MERIT is a proof-of-principle experiment which demonstrates the key target concepts for the production of muons required for a muon collider or a neutrino factory. The experiment was run at CERN utilizing 14 and 24 GeV proton beams from the PS. The key elements of the experiment include the impact of the proton beam with a free flowing mercury jet within the confines of a 15-T solenoid field. Results from the experiment are reported. [ABSTRACT FROM AUTHOR]

Earlier studies on the front end of a neutrino factory or muon collider have relied on a single simulation tool, ICOOL. We present here a cross-check against another simulation tool, G4beamline. We also perform a study to simplify the RF structure requirements by reducing the number of RF cavity frequencies and gradients. This investigation is also pertinent to engineering tolerances expected of these structures. We conclude with a discussion of future studies. [ABSTRACT FROM AUTHOR]

It is well-known that for unflavored leptogenesis there is in general no connection between low and high energy CP violation. We stress that for a non-unitary lepton mixing matrix this may not be the case. We give an illustrative example for this connection and show that the non-standard CP phases that are induced by non-unitarity can be responsible for observable effects in neutrino oscillation experiments as well as for the generation of the baryon asymmetry of the Universe. [ABSTRACT FROM AUTHOR]

We explore the possibility to explain the LSND [1] result in the context of extra-dimensional theories. If sterile neutrinos take shortcuts through extra dimensions, this results in altered neutrino dispersion relations. Active-sterile neutrino oscillations thus are modified and new types of resonances occur. [ABSTRACT FROM AUTHOR]

Finding the Standard Model scalar (Higgs) boson is arguably the single most important mission of the LHC. I review predictions for the Higgs boson mass based on stability and perturbativity arguments, taking into account neutrino oscillations. Primordial inflation based on the Coleman-Weinberg potential is briefly discussed. [ABSTRACT FROM AUTHOR]

We investigate cold rubidium plasmas in a particle trap that has the unique capability to simultaneously laser-cool and trap neutral atoms as well as to confine plasmas in magnetic fields of about three Tesla. The atom trap is a high-field Ioffe-Pritchard laser trap, while the plasma trap is a Ioffe-Penning trap that traps electrons and ions in separate wells. The observed plasma dynamics is characterized by a breathing-mode oscillation of the positive (ionic) plasma component, which feeds back on the behavior of the negative (electron) component of the plasma. At higher densities, the observed oscillations become nonlinear. The electron component has been found to undergo rapid cooling. We further report on the recombination of magnetized plasmas into Rydberg atoms in transient traps and quasi-steady-state traps. In transient traps, large numbers of recombined Rydberg atoms in high-lying states are observed. In quasi-steady-state traps, the measured numbers of recombined atoms are lower and the binding energies higher. [ABSTRACT FROM AUTHOR]

Recent measurements of total 8B solar neutrino flux comprising neutrinos of different flavors account for all the missing high energy 8B solar neutrinos and agree well with Standard Solar Model (SSM) calculations. Since only electron neutrinos should be produced at the center of the sun, so the observations of neutrinos of different flavors provide evidence in the support of neutrino flavor oscillation. However at present, the uncertainty on the measured 8B solar neutrino flux is over 10% and that on the predicted flux from SSM calculations is also over 10%. So it is important to improve upon the accuracy of both the measured and predicted 8B solar neutrino fluxes for a precise comparison between them. Such comparison should be important for better understanding of both neutrino and solar physics. The most uncertain parameter in the calculation of 8B solar neutrino flux using SSM is 7Be(p,γ)8B reaction rate at solar Gammow energy. This reaction rate is usually represented by S17(0) factor and so high precision measurement of S17(0) factor is required. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

The KamLAND collaboration recently published the first evidence for reactor antineutrino disappearance. The measured ratio of observed inverse β-decay events to the number expected from standard assumptions about ve propagation is 0.611±0.085(stat)±0.041(syst). Fewer ve’s were seen than expected at the 99.95% confidence level. In the context of two-flavor neutrino oscillations and CPT invariance, this measurement rules out all but the LMA region of solar neutrino oscillation parameter space. I summarize these first results and discuss the prospects for future oscillation measurements at KamLAND. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

We review the search for ve from μ+ decays at rest with the KARMEN experiment. A potential excess of ve-induced events as seen in the LSND experiment can be interpreted as evidence for vμ → ve or as indication of lepton flavor (LF) violation in μ+ decays. The KARMEN results show no hint for extra ve, thereby excluding large parameter areas for an oscillation signal as well as the LF violating μ+ decay at more 90% C.L. as source of the LSND ve excess. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

A summary of the present status of the charged lepton flavor violation search with muons is presented. The relevant measurements (g-2)μ, the μ + → e + γ decay and the direct muon-to-electron conversion projects are briefly reviewed. [ABSTRACT FROM AUTHOR]

Modern neutrino oscillation experiments use a ‘near to far’ ratio to observe oscillation; many systematic errors cancel in a ratio between the near detector's unoscillated event sample and the far detector's oscillated one. Similarly, MiniBooNE uses a νe to νμ ratio, which reduces any common uncertainty in both samples. Here, we discuss the systematic errors of MiniBooNE and how the νμ sample constrains the νe signal sample. [ABSTRACT FROM AUTHOR]

Some theories of new physics accounting for neutrino masses can give rise to a low-energy non-unitary leptonic mixing matrix. It is shown that the CP-asymmetries in the νμ→ντ channel are an excellent probe of such new physics. In adition, we clarify the relationship betweeen our framework and the so called “non-standard neutrino interactions” scenarios: the sensitivities explored here apply as well to such constructions, except for extremely fine-tuned cancellations. [ABSTRACT FROM AUTHOR]

An analysis of the neutrino oscillation physics capability of a low energy Neutrino Factory is presented, including a first simulation of detector efficiency and event energy threshold. [ABSTRACT FROM AUTHOR]

These proceedings provide a summary of results from a combined analysis of short-baseline (SBL) oscillation data, including data from LSND and MiniBooNE, under a 3 active +2 sterile neutrino oscillation hypothesis. The analysis is done within both a CP-conserving (CPC) and a CP-violating (CPV) framework. The implications for any possible leptonic CP violation that is allowed by a combined analysis of the null-SBL and LSND experiments are discussed in relation to the MiniBooNE experiment. [ABSTRACT FROM AUTHOR]