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Author T2K Collaboration (Abe, K. et al); Antonova, M.; Cervera-Villanueva, A.; Fernandez, P.; Izmaylov, A.; Novella, P.
Title Constraint on the matter-antimatter symmetry-violating phase in neutrino oscillations Type Journal Article
Year 2020 Publication Nature Abbreviated Journal Nature
Volume 580 Issue 7803 Pages 339-344
Keywords
Abstract The charge-conjugation and parity-reversal (CP) symmetry of fundamental particles is a symmetry between matter and antimatter. Violation of this CP symmetry was first observed in 1964(1), and CP violation in the weak interactions of quarks was soon established(2). Sakharov proposed(3) that CP violation is necessary to explain the observed imbalance of matter and antimatter abundance in the Universe. However, CP violation in quarks is too small to support this explanation. So far, CP violation has not been observed in non-quark elementary particle systems. It has been shown that CP violation in leptons could generate the matter-antimatter disparity through a process called leptogenesis(4). Leptonic mixing, which appears in the standard model's charged current interactions(5,6), provides a potential source of CP violation through a complex phase dCP, which is required by some theoretical models of leptogenesis(7-9). This CP violation can be measured in muon neutrino to electron neutrino oscillations and the corresponding antineutrino oscillations, which are experimentally accessible using accelerator-produced beams as established by the Tokai-to-Kamioka (T2K) and NOvA experiments(10,11). Until now, the value of dCP has not been substantially constrained by neutrino oscillation experiments. Here we report a measurement using long-baseline neutrino and antineutrino oscillations observed by the T2K experiment that shows a large increase in the neutrino oscillation probability, excluding values of dCP that result in a large increase in the observed antineutrino oscillation probability at three standard deviations (3 sigma). The 3 sigma confidence interval for delta(CP), which is cyclic and repeats every 2p, is [-3.41, -0.03] for the so-called normal mass ordering and [-2.54, -0.32] for the inverted mass ordering. Our results indicate CP violation in leptons and our method enables sensitive searches for matter-antimatter asymmetry in neutrino oscillations using accelerator-produced neutrino beams. Future measurements with larger datasets will test whether leptonic CP violation is larger than the CP violation in quarks.
Address (up) [Berguno, D. Bravo; Ishii, T.; Labarga, L.] Univ Autonoma Madrid, Dept Theoret Phys, Madrid, Spain
Corporate Author Thesis
Publisher Nature Publishing Group Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0028-0836 ISBN Medium
Area Expedition Conference
Notes WOS:000530151300023 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4388
Permanent link to this record
 
 
Author T2K Collaboration (Abe, K. et al); Antonova, M.; Cervera-Villanueva, A.; Fernandez, P.; Izmaylov, A.; Novella, P.
Title Measurement of the charged-current electron (anti-)neutrino inclusive cross-sections at the T2K off-axis near detector ND280 Type Journal Article
Year 2020 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 10 Issue 10 Pages 114 - 43pp
Keywords Other experiments
Abstract The electron (anti-)neutrino component of the T2K neutrino beam constitutes the largest background in the measurement of electron (anti-)neutrino appearance at the far detector. The electron neutrino scattering is measured directly with the T2K off-axis near detector, ND280. The selection of the electron (anti-)neutrino events in the plastic scintillator target from both neutrino and anti-neutrino mode beams is discussed in this paper. The flux integrated single differential charged-current inclusive electron (anti-)neutrino cross-sections, d sigma/dp and d sigma/d cos(theta), and the total cross-sections in a limited phase-space in momentum and scattering angle (p 300 MeV/c and theta <= 45 degrees) are measured using a binned maximum likelihood fit and compared to the neutrino Monte Carlo generator predictions, resulting in good agreement.
Address (up) [Berguno, D. Bravo; Ishii, T.; Labarga, L.] Univ Autonoma Madrid, Dept Theoret Phys, Madrid, Spain
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000583585900001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4589
Permanent link to this record
 
 
Author HARP Collaboration (Apollonio, M. et al); Burguet-Castell, J.; Cervera-Villanueva, A.; Gomez-Cadenas, J.J.; Martin-Albo, J.; Novella, P.; Sorel, M.
Title Measurements of forward proton production with incident protons and charged pions on nuclear targets at the CERN Proton Synchroton Type Journal Article
Year 2010 Publication Physical Review C Abbreviated Journal Phys. Rev. C
Volume 82 Issue 4 Pages 045208 - 33pp
Keywords
Abstract Measurements of the double-differential proton production cross-section d(2 sigma)/dpd Omega in the range of momentum 0.5 GeV/c <= p < 8.0 GeV/c and angle 0.05 rad <= theta < 0.25 rad in collisions of charged pions and protons on beryllium, carbon, aluminium, copper, tin, tantalum, and lead are presented. The data were taken with the large acceptance HARP detector in the T9 beam line of the CERN Proton Synchrotron. Incident particles were identified by an elaborate system of beam detectors and impinged on a target of 5% of a nuclear interaction length. The tracking and identification of the produced particles was performed using the forward spectrometer of the HARP experiment. Results are obtained for the double-differential cross-sections mainly at four incident beam momenta (3, 5, 8, and 12 GeV/c). Measurements are compared with predictions of the GEANT4 and MARS Monte Carlo generators.
Address (up) [Bonesini, M.; Ferri, F.] Sez INFN Milano Bicocca, Milan, Italy, Email: maurizio.bonesini@mib.infn.it
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0556-2813 ISBN Medium
Area Expedition Conference
Notes ISI:000283579000005 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 346
Permanent link to this record
 
 
Author T2K Collaboration (Abe, K. et al); Antonova, M.; Cervera-Villanueva, A.; Fernandez, P.; Izmaylov, A.; Novella, P.
Title First combined measurement of the muon neutrino and antineutrino charged-current cross section without pions in the final state at T2K Type Journal Article
Year 2020 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 101 Issue 11 Pages 112001 - 44pp
Keywords
Abstract This paper presents the first combined measurement of the double-differential muon neutrino and antineutrino charged-current cross sections with no pions in the final state on hydrocarbon at the off-axis near detector of the T2K experiment. The data analyzed in this work comprise 5.8 x 10(20) and 6.3 x 10(20) protons on target in neutrino and antineutrino mode respectively, at a beam energy peak of 0.6 GeV. Using the two measured cross sections, the sum, difference, and asymmetry were calculated with the aim of better understanding the nuclear effects involved in such interactions. The extracted measurements have been compared with the prediction from different Monte Carlo generators and theoretical models showing that the difference between the two cross sections have interesting sensitivity to nuclear effects.
Address (up) [Bravo Berguno, D.; Labarga, L.] Univ Autonoma Madrid, Dept Theoret Phys, Madrid 28049, Spain
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000537161300001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4418
Permanent link to this record
 
 
Author T2K Collaboration (Abe, K. et al); Antonova, M.; Cervera-Villanueva, A.; Fernandez, P.; Izmaylov, A.; Novella, P.
Title Search for Electron Antineutrino Appearance in a Long-Baseline Muon Antineutrino Beam Type Journal Article
Year 2020 Publication Physical Review Letters Abbreviated Journal Phys. Rev. Lett.
Volume 124 Issue 16 Pages 161802 - 8pp
Keywords
Abstract Electron antineutrino appearance is measured by the T2K experiment in an accelerator-produced antineutrino beam, using additional neutrino beam operation to constrain parameters of the Pontecorvo-Maki-Nakagawa-Sakata (PMNS) mixing matrix. T2K observes 15 candidate electron antineutrino events with a background expectation of 9.3 events. Including information from the kinematic distribution of observed events, the hypothesis of no electron antineutrino appearance is disfavored with a significance of 2.40s and no discrepancy between data and PMNS predictions is found. A complementary analysis that introduces an additional free parameter which allows non-PMNS values of electron neutrino and antineutrino appearance also finds no discrepancy between data and PMNS predictions.
Address (up) [Bravo Berguno, D.; Labarga, L.] Univ Autonoma Madrid, Dept Theoret Phys, Madrid, Spain
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9007 ISBN Medium
Area Expedition Conference
Notes WOS:000527135200004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4379
Permanent link to this record
 
 
Author T2K Collaboration (Abe, K. et al); Antonova, M.; Cervera-Villanueva, A.; Novella, P.
Title Simultaneous measurement of the muon neutrino charged-current cross section on oxygen and carbon without pions in the final state at T2K Type Journal Article
Year 2020 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 101 Issue 11 Pages 112004 - 32pp
Keywords
Abstract This paper reports the first simultaneous measurement of the double differential muon neutrino chargedcurrent cross section on oxygen and carbon without pions in the final state as a function of the outgoing muon kinematics, made at the ND280 off-axis near detector of the T2K experiment. The ratio of the oxygen and carbon cross sections is also provided to help validate various models' ability to extrapolate between carbon and oxygen nuclear targets, as is required in T2K oscillation analyses. The data are taken using a neutrino beam with an energy spectrum peaked at 0.6 GeV. The extracted measurement is compared with the prediction from different Monte Carlo neutrino-nucleus interaction event generators, showing particular model separation for very forward-going muons. Overall, of the models tested, the result is best described using local Fermi gas descriptions of the nuclear ground state with RPA suppression.
Address (up) [Bravo Berguno, D.; Labarga, L.] Univ Autonoma Madrid, Dept Theoret Phys, Madrid, Spain
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000540384300002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4435
Permanent link to this record
 
 
Author NEXT Collaboration (Byrnes, N.K. et al); Carcel, S.; Carrion, J.V.; Lopez, F.; Lopez-March, N.; Martin-Albo, J.; Muñoz Vidal, J.; Novella, P.; Querol, M.; Romo-Luque, C.; Sorel, M.; Uson, A.
Title NEXT-CRAB-0: a high pressure gaseous xenon time projection chamber with a direct VUV camera based readout Type Journal Article
Year 2023 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.
Volume 18 Issue 8 Pages P08006 - 33pp
Keywords Double-beta decay detectors; Optical detector readout concepts; Particle tracking detectors (Gaseous detectors); Time projection chambers
Abstract The search for neutrinoless double beta decay (0νββ) remains one of the most compelling experimental avenues for the discovery in the neutrino sector. Electroluminescent gas-phase time projection chambers are well suited to 0νββ searches due to their intrinsically precise energy resolution and topological event identification capabilities. Scalability to ton-and multi-ton masses requires readout of large-area electroluminescent regions with fine spatial resolution, low radiogenic backgrounds, and a scalable data acquisition system. This paper presents a detector prototype that records event topology in an electroluminescent xenon gas TPC via VUV image-intensified cameras. This enables an extendable readout of large tracking planes with commercial devices that reside almost entirely outside of the active medium. Following further development in intermediate scale demonstrators, this technique may represent a novel and enlargeable method for topological event imaging in 0νββ.
Address (up) [Byrnes, N. K.; Parmaksiz, I; Asaadi, J.; Baeza-Rubio, J.; Jones, B. J. P.; Mistry, K.; Moya, I. A.; Nygren, D. R.; Stogsdill, K.; Navarro, K. E.] Univ Texas Arlington, Dept Phys, Arlington, TX 76019 USA
Corporate Author Thesis
Publisher IOP Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1748-0221 ISBN Medium
Area Expedition Conference
Notes WOS:001084390900004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5764
Permanent link to this record
 
 
Author NEXT Collaboration (Cebrian, S. et al); Perez, J.; Alvarez, V.; Benlloch-Rodriguez, J.; Botas, A.; Carcel, S.; Carrion, J.V.; Diaz, J.; Felkai, R.; Ferrario, P.; Gomez-Cadenas, J.J.; Laing, A.; Liubarsky, I.; Lopez-March, N.; Martin-Albo, J.; Martinez, A.; Muñoz Vidal, J.; Musti, M.; Nebot-Guinot, M.; Novella, P.; Palmeiro, B.; Querol, M.; Renner, J.; Rodriguez, J.; Serra, L.; Simon, A.; Sorel, M.; Torrent, J.; Yahlali, N.
Title Radiopurity assessment of the energy readout for the NEXT double beta decay experiment Type Journal Article
Year 2017 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.
Volume 12 Issue Pages T08003 - 20pp
Keywords Double-beta decay detectors; Gamma detectors (scintillators, CZT, HPG, HgI etc); Search for radioactive and fissile materials; Time projection chambers
Abstract The “Neutrino Experiment with a Xenon Time-Projection Chamber” (NEXT) experiment intends to investigate the neutrinoless double beta decay of Xe-136, and therefore requires a severe suppression of potential backgrounds. An extensive material screening and selection process was undertaken to quantify the radioactivity of the materials used in the experiment. Separate energy and tracking readout planes using different sensors allow us to combine the measurement of the topological signature of the event for background discrimination with the energy resolution optimization. The design of radiopure readout planes, in direct contact with the gas detector medium, was especially challenging since the required components typically have activities too large for experiments demanding ultra-low background conditions. After studying the tracking plane, here the radiopurity control of the energy plane is presented, mainly based on gamma-ray spectroscopy using ultra-low background germanium detectors at the Laboratorio Subterraneo de Canfranc (Spain). All the available units of the selected model of photomultiplier have been screened together with most of the components for the bases, enclosures and windows. According to these results for the activity of the relevant radioisotopes, the selected components of the energy plane would give a contribution to the overall background level in the region of interest of at most 2.4 x 10(-4) counts keV(-1) kg(-1) y(-1), satisfying the sensitivity requirements of the NEXT experiment.
Address (up) [Cebrian, S.] Univ Zaragoza, Lab Fis Nucl Astroparticulas, Calle Pedro Cerbuna 12, Zaragoza, Spain, Email: scebrian@unizar.es
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1748-0221 ISBN Medium
Area Expedition Conference
Notes WOS:000414160600003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3348
Permanent link to this record
 
 
Author Double Chooz collaboration (de Kerret, H. et al); Novella, P.
Title Yields and production rates of cosmogenic Li-9 and He-8 measured with the Double Chooz near and far detectors Type Journal Article
Year 2018 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 11 Issue 11 Pages 053 - 20pp
Keywords Neutrino Detectors and Telescopes (experiments)
Abstract The yields and production rates of the radioisotopes Li-9 and He-8 created by cosmic muon spallation on C-12, have been measured by the two detectors of the Double Chooz experiment. The identical detectors are located at separate sites and depths, which means that they are subject to different muon spectra. The near (far) detector has an overburden of approximate to 120 m.w.e. (approximate to 300 m.w.e.) corresponding to a mean muon energy of 32.1 +/- 2.0 GeV (63.7 +/- 5.5 GeV). Comparing the data to a detailed simulation of the Li-9 and He-8 decays, the contribution of the He-8 radioisotope at both detectors is found to be compatible with zero. The observed Li-9 yields in the near and far detectors are 5.51 +/- 0.51 and 7.90 +/- 0.51, respectively, in units of 10(-8-1)g(-1)cm(2). The shallow overburdens of the near and far detectors give a unique insight when combined with measurements by KamLAND and Borexino to give the first multi-experiment, data driven relationship between the Li-9 yield and the mean muon energy according to the power law and Y-0 = (0.43 +/- 0.11) x 10(-8-1)g(-1)cm(2). This relationship gives future liquid scintillator based experiments the ability to predict their cosmogenic Li-9 background rates.
Address (up) [Chimenti, P.] Univ Estadual Londrina, BR-86057970 Londrina, Brazil, Email: vsibille@mit.edu;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000450197100001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3802
Permanent link to this record
 
 
Author Double Chooz collaboration (de Kerret, H. et al); Novella, P.
Title Double Chooz theta(13) measurement via total neutron capture detection Type Journal Article
Year 2020 Publication Nature Physics Abbreviated Journal Nat. Phys.
Volume 16 Issue Pages 558-564
Keywords
Abstract Neutrinos were assumed to be massless particles until the discovery of the neutrino oscillation process. This phenomenon indicates that the neutrinos have non-zero masses and the mass eigenstates (nu(1), nu(2), nu(3)) are mixtures of their flavour eigenstates (nu(e), nu(mu), nu(tau)). The oscillations between different flavour eigenstates are described by three mixing angles (theta(12), theta(23), theta(13)), two differences of the squared neutrino masses of the nu(2)/nu(1) and nu(3)/nu(1) pairs and a charge conjugation parity symmetry violating phase delta(CP). The Double Chooz experiment, located near the Chooz Electricite de France reactors, measures the oscillation parameter theta(13) using reactor neutrinos. Here, the Double Chooz collaboration reports the measurement of the mixing angle theta(13) with the new total neutron capture detection technique from the full data set, yielding sin(2)(2 theta(13)) = 0.105 +/- 0.014. This measurement exploits the multidetector configuration, the isoflux baseline and data recorded when the reactors were switched off. In addition to the neutrino mixing angle measurement, Double Chooz provides a precise measurement of the reactor neutrino flux, given by the mean cross-section per fission <sigma(f)& rang; = (5.71 +/- 0.06) x 10(-43) cm(2) per fission, and reports an empirical model of the distortion in the reactor neutrino spectrum. The Double Chooz collaboration reports the neutrino oscillation parameter theta(13) from a measurement of the disappearance of reactor anti-electron neutrinos with the total neutron capture technique.
Address (up) [de Kerret, H.; Cabrera, A.; Dawson, J., V; Givaudan, A.; Gomez, H.; Hourlier, A.; Karakac, M.; Kryn, D.; Lasserres, T.; Obolensky, M.; Onillon, A.; Suekane, F.; Wagner, S.] Sorbonne Paris Cite Univ, Observ Paris, CEA IRFU, APC,CNRS IN2P3, Paris, France, Email: christian.buck@mpi-hd.mpg.de;
Corporate Author Thesis
Publisher Nature Publishing Group Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1745-2473 ISBN Medium
Area Expedition Conference
Notes WOS:000528019800001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4389
Permanent link to this record