Search results for "Oscillation"
showing 10 items of 1257 documents
Physics of nuclear processes triggered by the interplay of strong and weak interactions
2012
Neutrinoless double beta (0νββ) decay of nuclei is a process that requires the neutrino to be a massive Majorana particle and thus cannot proceed in the standard model of electro-weak interactions. Recent results of the neutrino-oscillation experiments have produced accurate information on the mixing of neutrinos and their squared mass differences. The 0νββ decay takes place in atomic nuclei where it can be observed, at least in principle, by underground neutrino experiments. The information about the weak-interaction observables, like the neutrino mass, has to be filtered from the data through the nuclear matrix elements (NMEs). In this article recent work of the Jyv¨askyl¨a group on the N…
Neutrino masses: evidences and implications
2014
I give an overview of the evidences for neutrino masses and mixing, the associated neutrino mass generation schemes, as well as the resulting implications in particle physics experiments and cosmology.
Hunt for θ13with LENA
2012
In a hunt for by far missing neutrino mixing angle ?13 the accelerator experiments have recently indicated non-zero value and the dedicated reactor neutrino experiments are moving towards the data-taking phase to confirm that. The small effect of ?13 to the neutrino oscillation probabilities can be also complementarily probed using artificially made source of mono-chromatic neutrinos with low energies originated from electron capture processes. Due to the small energy of neutrino and tiny interaction cross section, and the expected scale of ?13 support the use of large liquid scintillation detector. In this work, the estimated sensitivities for measurement of mixing angle ?13 is presented i…
Testing the Standard Model and beyond with the LENA proposal
2014
We discuss the possibility of a precision measurement of the electroweak mixing angle and a probe for new physics in the leptonic process of neutrino electron scattering. In the new physics schemes we explore the case of non standard neutrino interactions (NSI). The LENA proposal, currently under discussion, considers a large detector and the use of an articial, 51 Cr, radioactive neutrino source with of 5 MCi intensity. We also discuss the possible use of the solar neutrino
Omnibus experiment: CPT and CP violation with sterile neutrinos
2016
We propose to probe both the CPT and CP violation together with the search for sterile neutrinos in one do-it-all experiment. This omnibus experiment would utilize neutrino oscillometry with large scintillator detectors like LENA, JUNO or RENO-50 and manmade radioactive sources similar to the ones used by the GALLEX experiment. Our calculations indicate that such an experiment is realistic and could be performed in parallel to the main research plan for JUNO, LENA, or RENO-50. Assuming as the starting point the values of the oscillation parameters indicated by the current global fit (in 3 active + 1 sterile scenario) and requiring at least 5 sigma confidence level, we estimate that with the…
Search for sterile neutrinos with SOX: Monte Carlo studies of the experiment sensitivity and systematic effects
2020
Abstract Some neutrino experiments reveal anomalous results which can make room for new physics beyond the three-flavor neutrino oscillation model. These hints suggest the existence of sterile neutrinos with mass m <eV. SOX will be a short-baseline disappearance experiment aiming to test this hypotesis, performed with the liquid scintillator detector Borexino at Gran Sasso National Laboratory in Italy [1]. Due to the good energy and position resolution, a light sterile neutrino can create an oscillatory pattern in the signal. The SOX sensitivity, the related analysis and systematics will be briefly discussed.
Active-active and active-sterile neutrino oscillation solutions to the atmospheric neutrino anomaly
1998
We perform a fit to the full data set corresponding to 33.3 kt-yr of data of the Super-Kamiokande experiment as well as to all other experiments in order to compare the two most likely solutions to the atmospheric neutrino anomaly in terms of oscillations in the $\nu_\mu \to \nu_\tau$ and $\nu_\mu \to \nu_s$ channels. Using state-of-the-art atmospheric neutrino fluxes we have determined the allowed regions of oscillation parameters for both channels. We find that the $\Delta m^2$ values for the active-sterile oscillations (both for positive and negative $\Delta m^2$) are higher than for the $\nu_\mu \to \nu_\tau$ case, and that the increased Super-Kamiokande sample slightly favours $\nu_\mu…
Simulation and experimental investigations on dynamic after cavity interaction (ACI)
2010
In recent years, the so called after cavity interaction (ACI) in high power gyrotrons operating in the 100–200 GHz range gained attention as an influence factor on overall efficiency. While investigations concentrated on ACI as a stationary effect until now, recent simulations show that an undesired interaction in the uptaper region can also result in additional parasitic oscillations. In this paper, such non-stationary, dynamic processes are investigated in first simulations and experiments.
Linking Jet Emission, X‐Ray States, and Hard X‐Ray Tails in the Neutron Star X‐Ray Binary GX 17 \documentclass{aastex} \usepackage{amsbsy} \usepackag…
2007
We present the results from simultaneous radio (Very Large Array) and X-ray (Rossi-X-ray Timing Explorer) observations of the Z-type neutron star X-ray binary GX~17+2. The aim is to assess the coupling between X-ray and radio properties throughout its three rapidly variable X-ray states and during the time-resolved transitions. These observations allow us, for the first time, to investigate quantitatively the possible relations between the radio emission and the presence of the hard X-ray tails and the X-ray state of the source. The observations show: 1) a coupling between the radio jet emission and the X-ray state of the source, i.e. the position in the X-ray hardness-intensity diagram (HI…
Numerical study of emission and dynamics from a TDE-powered jet
2012
A transient event Swift J1644+57 is thought to be caused by the emission from a collimated relativistic jet. The jet, powered by the sudden onset of accretion onto a supermassive black hole following the tidal disruption of a star, collides with the gaseous circumnuclear medium and produces forward and reverse shocks which emit synchrotron radiation. We perform 1D and 2D relativistic hydrodynamic simulations using the MRGENESIS code. The aim of the simulations is to study the dynamics of a jet thought to exist in transient events such as Swift J1644+57, as discussed in recent literature. We discuss 1D and 2D jet evolution, on-axis radio light curves and differences between 1D and 2D jet dyn…