Search results for " Neutrino oscillation"
showing 10 items of 13 documents
Measurement of the atmospheric ?µ energy spectrum from 100 GeV to 200 TeV with the ANTARES telescope
2013
Atmospheric neutrinos are produced during cascades initiated by the interaction of primary cosmic rays with air nuclei. In this paper, a measurement of the atmospheric energy spectrum in the energy range 0.1-200 TeV is presented, using data collected by the ANTARES underwater neutrino telescope from 2008 to 2011. Overall, the measured flux is similar to 25 % higher than predicted by the conventional neutrino flux, and compatible with the measurements reported in ice. The flux is compatible with a single power-law dependence with spectral index gamma (meas)=3.58 +/- 0.12. With the present statistics the contribution of prompt neutrinos cannot be established.
Time projection chambers for the T2K near detectors
2011
The T2K experiment is designed to study neutrino oscillation properties by directing a high intensity neutrino beam produced at J-PARC in Tokai, Japan, towards the large Super-Kamiokande detector located 295 km away, in Kamioka, Japan. The experiment includes a sophisticated near detector complex, 280 m downstream of the neutrino production target in order to measure the properties of the neutrino beam and to better understand neutrino interactions at the energy scale below a few GeV. A key element of the near detectors is the ND280 tracker, consisting of two active scintillator–bar target systems surrounded by three large time projection chambers (TPCs) for charged particle tracking. The d…
The T2K Experiment
2011
The T2K experiment is a long-baseline neutrino oscillation experiment. Its main goal is to measure the last unknown lepton sector mixing angle {\theta}_{13} by observing {\nu}_e appearance in a {\nu}_{\mu} beam. It also aims to make a precision measurement of the known oscillation parameters, {\Delta}m^{2}_{23} and sin^{2} 2{\theta}_{23}, via {\nu}_{\mu} disappearance studies. Other goals of the experiment include various neutrino cross section measurements and sterile neutrino searches. The experiment uses an intense proton beam generated by the J-PARC accelerator in Tokai, Japan, and is composed of a neutrino beamline, a near detector complex (ND280), and a far detector (Super-Kamiokande)…
Precise measurement of the neutrino mixing parameter θ23 from muon neutrino disappearance in an off-axis beam
2014
New data from the T2K neutrino oscillation experiment produce the most precise measurement of the neutrino mixing parameter theta_{23}. Using an off-axis neutrino beam with a peak energy of 0.6 GeV and a data set corresponding to 6.57 x 10^{20} protons on target, T2K has fit the energy-dependent nu_mu oscillation probability to determine oscillation parameters. Marginalizing over the values of other oscillation parameters yields sin^2 (theta_{23}) = 0.514 +0.055/-0.056 (0.511 +- 0.055), assuming normal (inverted) mass hierarchy. The best-fit mass-squared splitting for normal hierarchy is Delta m^2_{32} = (2.51 +- 0.10) x 10^{-3} eV^2/c^4 (inverted hierarchy: Delta m^2_{13} = (2.48 +- 0.10) …
PINGU: a vision for neutrino and particle physics at the South Pole
2017
The Precision IceCube Next Generation Upgrade (PINGU) is a proposed low-energy in-fill extension to the IceCube Neutrino Observatory. With detection technology modeled closely on the successful IceCube example, PINGU will provide a 6Mton effective mass for neutrino detection with an energy threshold of a few GeV. With an unprecedented sample of over 60,000 atmospheric neutrinos per year in this energy range, PINGU will make highly competitive measurements of neutrino oscillation parameters in an energy range over an order of magnitude higher than long-baseline neutrino beam experiments. PINGU will measure the mixing parameters $\theta_{\rm 23}$ and $\Delta m^2_{\rm 32}$, including the octan…
Feasibility and physics potential of detecting $^8$B solar neutrinos at JUNO
2021
The Jiangmen Underground Neutrino Observatory (JUNO) features a 20 kt multi-purpose underground liquid scintillator sphere as its main detector. Some of JUNO's features make it an excellent location for 8B solar neutrino measurements, such as its low-energy threshold, high energy resolution compared with water Cherenkov detectors, and much larger target mass compared with previous liquid scintillator detectors. In this paper, we present a comprehensive assessment of JUNO's potential for detecting 8B solar neutrinos via the neutrino-electron elastic scattering process. A reduced 2 MeV threshold for the recoil electron energy is found to be achievable, assuming that the intrinsic radioactive …
Reactor antineutrino detection in Double Chooz experiment: Techniques for background reduction
2014
Abstract A crucial task for the Double Chooz reactor antineutrino experiment is the thorough study of the different backgrounds in the detector. Newly developed background reduction techniques minimize the impact of the backgrounds on our sensitivity. Moreover, only a precision and accuracy measurement of the residual background would allow to measure the mixing angle θ 13 with high precision. Neutrino coincidence signals are imitated by signals produced in several others physics processes: accidental coincidences of single events (accidental background), as well as correlated events induced by cosmic muons, including stopping muons, fast neutrons and spallation isotopes Li 9 /He 8 . The Do…
A $B_4C$-silicon target for the detection of neutrino interactions
1998
This note describes the construction of a target for neutrino interactions composed of passive boron carbide plates interleaved with silicon microstrip detectors. The target contains four layers of passive material with a total mass of 45 kg and 600 single--sided silicon microstrip detectors with a total surface of 1.14 m$^2$ distributed over five layers. It is installed in the NOMAD spectrometer at the CERN SPS neutrino beam. During the 1997 run about 8000 \nm\ charged current interactions were estimated to have occurred in the target. For these events it will be possible to perform a precise measurement of both vertex and kinematical variables. This will provide invaluable experience towa…
Performance of long modules of silicon microstrip detectors
1998
This note describes the performance of modules assembled with up to twelve silicon microstrip detectors. These modules were built for the instrumented Silicon Target (STAR) that has been installed in the NOMAD spectrometer. Laboratory and test beam results are compared with model predictions. For a module of nine detectors, test beam results indicate a signal--to--noise ratio of 19, a hit finding efficiency of 99.8\% and a spatial resolution of 6.0 $\mu$m. Laboratory measurements indicate that modules of twelve detectors exhibit a signal--to--noise ratio of the order of 16.
Recent results from Borexino and the first real time measure of solar pp neutrinos
2014
International audience; The Borexino detector was built starting from 1996 in the underground hall C of Gran Sasso National Laboratory (LNGS) in Italy under about 1400 m of rock (3800 m.w.e) and it is mostly aimed to the study in real-time of the low-energy solar neutrinos.Since the beginning of data taking, in May 2007, the unprecedented detector radio-purity made the performances of the detector unique: a milestone has been very recently achieved with the measurement of solar pp neutrino flux, providing the first direct observation in real time of the key fusion reaction powering the Sun.In this contribution the most important Borexino achievements to the fields of solar, geo-neutrino and…