260 research outputs found
Search of neutrino CPV with the T2K experiment
In the T2K (Tokai-to-Kamioka) experiment, an off-axis neutrino beam with a peak energy of ∼ 0.6 GeV is produced at the J-PARC accelerator facility, with the flavour content dominated by either muon neutrinos or muon antineutrinos, depending on the choice of the polarity of the magnetic focusing horns. The neutrino beam is detected first in the near detector ND280, where the flavour
composition of the incoming neutrino flux is not expected to be affected by oscillation, and then travels 295 km to the far detector Super-Kamiokande, where oscillation significantly affects the flavour composition. We report the results of a joint analysis of neutrino and anti-neutrino oscillations at T2K, obtained by collecting a total statistic of 2.25×1021 protons-on-target (POT). Currently T2K can claim the world leading sensitivity to the neutrino-sector CPV, thanks to a number of critical improvements in the oscillation analysis combined together with a stable operation at intense beam power. In fact, T2K is the first experiment able to reject the CP-conserving values of δCP at 2σ C.L
A narrow band neutrino beam with high precision flux measurements
The ENUBET facility is a proposed narrow band neutrino beam where lepton
production is monitored at single particle level in the instrumented decay
tunnel. This facility addresses simultaneously the two most important
challenges for the next generation of cross section experiments: a superior
control of the flux and flavor composition at source and a high level of
tunability and precision in the selection of the energy of the outcoming
neutrinos. We report here the latest results in the development and test of the
instrumentation for the decay tunnel. Special emphasis is given to irradiation
tests of the photo-sensors performed at INFN-LNL and CERN in 2017 and to the
first application of polysiloxane-based scintillators in high energy physics.Comment: Poster presented at NuPhys2017 (London, 20-22 December 2017). 5
pages, 2 figure
The ENUBET Beamline
The ENUBET ERC project (2016-2021) is studying a narrow band neutrino beam
where lepton production can be monitored at single particle level in an
instrumented decay tunnel. This would allow to measure and
cross sections with a precision improved by about one order of
magnitude compared to present results. In this proceeding we describe a first
realistic design of the hadron beamline based on a dipole coupled to a pair of
quadrupole triplets along with the optimisation guidelines and the results of a
simulation based on G4beamline. A static focusing design, though less efficient
than a horn-based solution, results several times more efficient than
originally expected. It works with slow proton extractions reducing drastically
pile-up effects in the decay tunnel and it paves the way towards a time-tagged
neutrino beam. On the other hand a horn-based transferline would ensure higher
yields at the tunnel entrance. The first studies conducted at CERN to implement
the synchronization between a few ms proton extraction and a horn pulse of 2-10
ms are also described.Comment: Poster presented at NuPhys2018 (London 19-21 December 2018). 4 pages,
3 figure
Proton-proton elastic scattering at the LHC energy of {\surd} = 7 TeV
Proton-proton elastic scattering has been measured by the TOTEM experiment at
the CERN Large Hadron Collider at {\surd}s = 7 TeV in dedicated runs with the
Roman Pot detectors placed as close as seven times the transverse beam size
(sbeam) from the outgoing beams. After careful study of the accelerator optics
and the detector alignment, |t|, the square of four-momentum transferred in the
elastic scattering process, has been determined with an uncertainty of d t =
0.1GeV p|t|. In this letter, first results of the differential cross section
are presented covering a |t|-range from 0.36 to 2.5GeV2. The differential
cross-section in the range 0.36 < |t| < 0.47 GeV2 is described by an
exponential with a slope parameter B = (23.6{\pm}0.5stat {\pm}0.4syst)GeV-2,
followed by a significant diffractive minimum at |t| =
(0.53{\pm}0.01stat{\pm}0.01syst)GeV2. For |t|-values larger than ~ 1.5GeV2, the
cross-section exhibits a power law behaviour with an exponent of -7.8_\pm}
0.3stat{\pm}0.1syst. When compared to predictions based on the different
available models, the data show a strong discriminative power despite the small
t-range covered.Comment: 12pages, 5 figures, CERN preprin
First Results from the TOTEM Experiment
The first physics results from the TOTEM experiment are here reported,
concerning the measurements of the total, differential elastic, elastic and
inelastic pp cross-section at the LHC energy of = 7 TeV, obtained
using the luminosity measurement from CMS. A preliminary measurement of the
forward charged particle distribution is also shown.Comment: Conference Proceeding. MPI@LHC 2010: 2nd International Workshop on
Multiple Partonic Interactions at the LHC. Glasgow (UK), 29th of November to
the 3rd of December 201
Elastic Scattering and Total Cross-Section in p+p reactions measured by the LHC Experiment TOTEM at sqrt(s) = 7 TeV
Proton-proton elastic scattering has been measured by the TOTEM experiment at
the CERN Large Hadron Collider at TeV in special runs with the
Roman Pot detectors placed as close to the outgoing beam as seven times the
transverse beam size. The differential cross-section measurements are reported
in the |t|-range of 0.36 to 2.5 GeV^2. Extending the range of data to low t
values from 0.02 to 0.33 GeV^2,and utilizing the luminosity measurements of
CMS, the total proton-proton cross section at sqrt(s) = 7 TeV is measured to be
(98.3 +- 0.2(stat) +- 2.8(syst)) mb.Comment: Proceedings of the XLI International Symposium on Multiparticle
Dynamics. Accepted for publication in Prog. Theor. Phy
Search for short baseline nu(e) disappearance with the T2K near detector
8 pages, 6 figures, submitted to PRD rapid communication8 pages, 6 figures, submitted to PRD rapid communicationWe thank the J-PARC staff for superb accelerator performance and the CERN NA61 collaboration for providing valuable particle production data. We acknowledge the support of MEXT, Japan; NSERC, NRC and CFI, Canada; Commissariat `a l’Energie Atomique and Centre National de la Recherche Scientifique–Institut National de Physique Nucle´aire et de Physique des Particules, France; DFG, Germany; INFN, Italy; National Science Centre (NCN), Poland; Russian Science Foundation, RFBR and Ministry of Education and Science, Russia; MINECO and European Regional Development Fund, Spain; Swiss National Science Foundation and State Secretariat for Education, Research and Innovation, Switzerland; STFC, UK; and DOE, USA. We also thank CERN for the UA1/NOMAD magnet, DESY for the HERA-B magnet mover system, NII for SINET4, the WestGrid and SciNet consortia in Compute Canada, GridPP, UK. In addition participation of individual researchers and institutions has been further supported by funds from ERC (FP7), EU; JSPS, Japan; Royal Society, UK; DOE Early Career program, USA
A Long Baseline Neutrino Oscillation Experiment Using J-PARC Neutrino Beam and Hyper-Kamiokande
Document submitted to 18th J-PARC PAC meeting in May 2014. 50 pages, 41 figuresDocument submitted to 18th J-PARC PAC meeting in May 2014. 50 pages, 41 figuresDocument submitted to 18th J-PARC PAC meeting in May 2014. 50 pages, 41 figuresHyper-Kamiokande will be a next generation underground water Cherenkov detector with a total (fiducial) mass of 0.99 (0.56) million metric tons, approximately 20 (25) times larger than that of Super-Kamiokande. One of the main goals of Hyper-Kamiokande is the study of asymmetry in the lepton sector using accelerator neutrino and anti-neutrino beams. In this document, the physics potential of a long baseline neutrino experiment using the Hyper-Kamiokande detector and a neutrino beam from the J-PARC proton synchrotron is presented. The analysis has been updated from the previous Letter of Intent [K. Abe et al., arXiv:1109.3262 [hep-ex]], based on the experience gained from the ongoing T2K experiment. With a total exposure of 7.5 MW 10 sec integrated proton beam power (corresponding to protons on target with a 30 GeV proton beam) to a -degree off-axis neutrino beam produced by the J-PARC proton synchrotron, it is expected that the phase can be determined to better than 19 degrees for all possible values of , and violation can be established with a statistical significance of more than () for () of the parameter space
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