Flavour-conserving oscillations of Dirac-Majorana neutrinos

We analyze both chirality-changing and chirality-preserving transitions of Dirac-Majorana neutrinos. In vacuum, the first ones are suppressed with respect to the others due to helicity conservation and the interactions with a (``normal'') medium practically does not affect the expressions of the probabilities for these transitions, even if the amplitudes of oscillations slightly change. For usual situations involving relativistic neutrinos we find no resonant enhancement for all flavour-conserving transitions. However, for very light neutrinos propagating in superdense media, the pattern of oscillations $\nu_L \to \nu^C_L$ is dramatically altered with respect to the vacuum case, the transition probability practically vanishing. An application of this result is envisaged.Comment: 14 pages, latex 2E, no figure

Seesaw model in SO(10) with an upper limit on right-handed neutrino masses

In the framework of SO(10) gauge unification and the seesaw mechanism, we show that the upper bound on the mass of the heaviest right-handed neutrino $M_{R_3} < 3 \times 10^{11}$ GeV, given by the Pati-Salam intermediate scale of $B-L$ spontaneous symmetry breaking, constrains the observables related to the left-handed light neutrino mass matrix. We assume such an upper limit on the masses of right-handed neutrinos and, as a first approximation, a Cabibbo form for the matrix $V^L$ that diagonalizes the Dirac neutrino matrix $m_D$. Using the inverse seesaw formula, we show that our hypotheses imply a triangular relation in the complex plane of the light neutrino masses with the Majorana phases. We obtain normal hierarchy with an absolute scale for the light neutrino spectrum. Two regions are allowed for the lightest neutrino mass $m_1$ and for the Majorana phases, implying predictions for the neutrino mass measured in Tritium decay and for the double beta decay effective mass $||$.Comment: 14 pages. Revised version with 3 figure

Low exposure long-baseline neutrino oscillation sensitivity of the DUNE experiment

Trabajo realizado por más de doscientos autores.The Deep Underground Neutrino Experiment (DUNE) will produce world-leading neutrino oscillation measurements over the lifetime of the experiment. In this work, we explore DUNE’s sensitivity to observe charge-parity violation (CPV) in the neutrino sector, and to resolve the mass ordering, for exposures of up to 100 kiloton-megawatt-calendar years (kt-MW-CY), where calendar years include an assumption of 57% accelerator uptime based on past accelerator performance at Fermilab. The analysis includes detailed uncertainties on the flux prediction, the neutrino interaction model, and detector effects. We demonstrate that DUNE will be able to unambiguously resolve the neutrino mass ordering at a 4σ (5σ) level with a 66 (100) kt-MW-CY far detector exposure, and has the ability to make strong statements at significantly shorter exposures depending on the true value of other oscillation parameters, with a median sensitivity of 3σ for almost all true δCP values after only 24 kt-MW-CY. We also show that DUNE has the potential to make a robust measurement of CPV at a 3σ level with a 100 kt-MW-CY exposure for the maximally CP-violating values δCP=±π/2. Additionally, the dependence of DUNE’s sensitivity on the exposure taken in neutrino-enhanced and antineutrino-enhanced running is discussed. An equal fraction of exposure taken in each beam mode is found to be close to optimal when considered over the entire space of interest

Scintillation light detection in the 6-m drift-length ProtoDUNE Dual Phase liquid argon TPC

Trabajo realizado por más de doscientos autores.DUNE is a dual-site experiment for long-baseline neutrino oscillation studies, neutrino astrophysics and nucleon decay searches. ProtoDUNE Dual Phase (DP) is a 6 × 6 × 6 m3 liquid argon time-projection-chamber (LArTPC) that recorded cosmic-muon data at the CERN Neutrino Platform in 2019–2020 as a prototype of the DUNE Far Detector. Charged particles propagating through the LArTPC produce ionization and scintillation light. The scintillation light signal in these detectors can provide the trigger for non-beam events. In addition, it adds precise timing capabilities and improves the calorimetry measurements. In ProtoDUNE-DP, scintillation and electroluminescence light produced by cosmic muons in the LArTPC is collected by photomultiplier tubes placed up to 7 m away from the ionizing track. In this paper, the ProtoDUNE-DP photon detection system performance is evaluated with a particular focus on the different wavelength shifters, such as PEN and TPB, and the use of Xe-doped LAr, considering its future use in giant LArTPCs. The scintillation light production and propagation processes are analyzed and a comparison of simulation to data is performed, improving understanding of the liquid argon properties

Design, construction and operation of the ProtoDUNE-SP Liquid Argon TPC

Artículo realizado por más de cien autores.The ProtoDUNE-SP detector is a single-phase liquid argon time projection chamber (LArTPC) that was constructed and operated in the CERN North Area at the end of the H4 beamline. This detector is a prototype for the first far detector module of the Deep Underground Neutrino Experiment (DUNE), which will be constructed at the Sandford Underground Research Facility (SURF) in Lead, South Dakota, U.S.A. The ProtoDUNE-SP detector incorporates full-size components as designed for DUNE and has an active volume of 7 6 7 2 m3. The H4 beam delivers incident particles with well-measured momenta and high-purity particle identification. ProtoDUNE-SP’s successful operation between 2018 and 2020 demonstrates the effectiveness of the single-phase far detector design. This paper describes the design, construction, assembly and operation of the detector components

Separation of track- and shower-like energy deposits in ProtoDUNE-SP using a convolutional neural network

Trabajo realizado por más de doscientos autores.Liquid argon time projection chamber detector technology provides high spatial and calorimetric resolutions on the charged particles traversing liquid argon. As a result, the technology has been used in a number of recent neutrino experiments, and is the technology of choice for the Deep Underground Neutrino Experiment (DUNE). In order to perform high precision measurements of neutrinos in the detector, final state particles need to be effectively identified, and their energy accurately reconstructed. This article proposes an algorithm based on a convolutional neural network to perform the classification of energy deposits and reconstructed particles as track-like or arising from electromagnetic cascades. Results from testing the algorithm on experimental data from ProtoDUNE-SP, a prototype of the DUNE far detector, are presented. The network identifies track- and shower-like particles, as well as Michel electrons, with high efficiency. The performance of the algorithm is consistent between experimental data and simulation

Idade, peso e prenhez de novilhas Nelore mocha.

Objetivou-se com este trabalho caracterizar idade, peso e prenhez em novilhas Nelore. Utilizou-se 56 novilhas da raça Nelore, desafiadas com touros para a determinação da idade a primeira prenhez. As novilhas foram pesadas a cada dois meses dos 16 aos 32 meses de idade. Os resultados evidenciaram idade média de 24,10 ± 5,13 meses e peso médio de 304,83 ± 48,23 kg nas 37 novilhas prenhas. Concluiu-se que a idade a primeira prenhez das novilhas Nelore observada neste experimento encontra-se próxima ao descrito na literatura para fêmeas zebuínas, havendo a necessidade de maiores estudos, relacionados ao melhoramento genético e/ou alternativas de manejo, a fim de antecipar a ocorrência da primeira prenhez

A Predictive Minimal Model for Neutrino Masses and Mixings

A model is considered in which the scale of the heavy singlet neutrinos is a few orders of magnitude below the grand unification scale and where right-handed vector bosons play still a negligible role. In a basis with diagonal up-quark and Dirac-neutrino mass matrices it is assumed that the heavy neutrino mass matrix has only zero elements in its diagonal, in analogy to the light neutrino mass matrix in the Zee model. Connecting then the remaining matrix elements with the small parameter describing the hierarchy of quark masses and mixings and by assuming commutativity of the charged lepton with the down-quark mass matrix, the calculation of all neutrino properties can be performed in terms of the two mass differences relevant for atmospheric and solar neutrino oscillations. CP-violation is directly related to CP-violation in the quark sector.Comment: revtex, 9 pages, two references added, to be published in Phys. Rev. D presented at Neutrino' 2000, Sudbury, Canad

Eficiência de fungicidas no controle da ferrugem asiática da soja no DF (PAD/DF) - ensaio cooperativo safra 2011/2012.

Como parte integrante da rede de ensaios cooperativos do consórcio antiferrugem, foi instalado experimento na Fazenda Dani, PAD/DF, Brasília, DF. A cultivar utilizada foi a MSoy 7908, inoculada e semeada com espaçamento de 0,50 m entre linhas e 12 pl/m. O delineamento experimental foi blocos ao acaso, com 16 tratamentos e 4 repetições. As repetições foram constituídas por parcelas de 6 linhas de 6 m de comprimento. Os produtos testados foram T1 Testemunha, T2 Folicur, T3 Alto 100, T4 Priori + Nimbus, T5 Priori Xtra + Nimbus, T6 Opera + Assist, T7 Aproach Prima + Nimbus, T8 Fox + Áureo, T9 Domark XL + Nimbus, T10 BAS 702 F EC + Assist T11 NTX3900, T12 IBIQF11165 + IHAROL, T13 Azimut + Nimbus, T14 Horos + Nimbus, T15 Guapo Ultra + Nimbus e T16 CHABF 0332511 + Nimbus, nas doses recomendadas pelas empresas. Após a análise dos dados, verificou-se que houve diferença estatística significativa entre os produtos, quanto à severidade da doença, no estádio R6, sendo que os tratamentos T8 (Fox + Áureo), T10 (BAS 702 F EC + Assist), T14 (Horos + Nimbus), T7 (Aproach Prima + Nimbus) apresentaram mais baixa severidade. Quanto ao rendimento de grãos, os tratamentos que apresentaram as melhores produtividades foram o T8 (Fox + Áureo), T10 (BAS 702 F EC + Assist), T9 (Domark XL + Nimbus), T13 (Azimut + Nimbus). A diferença de rendimento de grãos entre o melhor tratamento T8 (Fox + Áureo) e a testemunha T1 foi equivalente a 1723 kg.ha-1

Search for dark matter produced in association with a Standard Model Higgs boson decaying into b-quarks using the full Run 2 dataset from the ATLAS detector

Abstract: The production of dark matter in association with Higgs bosons is predicted in several extensions of the Standard Model. An exploration of such scenarios is presented, considering final states with missing transverse momentum and b-tagged jets consistent with a Higgs boson. The analysis uses proton-proton collision data at a centre-of-mass energy of 13 TeV recorded by the ATLAS experiment at the LHC during Run 2, amounting to an integrated luminosity of 139 fb−1 . The analysis, when compared with previous searches, benefits from a larger dataset, but also has further improvements providing sensitivity to a wider spectrum of signal scenarios. These improvements include both an optimised event selection and advances in the object identification, such as the use of the likelihood-based significance of the missing transverse momentum and variable-radius track-jets. No significant deviation from Standard Model expectations is observed. Limits are set, at 95% confidence level, in two benchmark models with two Higgs doublets extended by either a heavy vector boson Z 0 or a pseudoscalar singlet a and which both provide a dark matter candidate χ. In the case of the two-Higgs-doublet model with an additional vector boson Z 0 , the observed limits extend up to a Z 0 mass of 3 TeV for a mass of 100 GeV for the dark matter candidate. The two-Higgs-doublet model with a dark matter particle mass of 10 GeV and an additional pseudoscalar a is excluded for masses of the a up to 520 GeV and 240 GeV for tan β = 1 and tan β = 10 respectively. Limits on the visible cross-sections are set and range from to 0.05 fb to 3.26 fb, depending on the missing transverse momentum and b-quark jet multiplicity requirements