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1.
Phys Rev Lett ; 125(13): 131802, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-33034464

RESUMO

We report the final measurement of the neutrino oscillation parameters Δm_{32}^{2} and sin^{2}θ_{23} using all data from the MINOS and MINOS+ experiments. These data were collected using a total exposure of 23.76×10^{20} protons on target producing ν_{µ} and ν[over ¯]_{µ} beams and 60.75 kt yr exposure to atmospheric neutrinos. The measurement of the disappearance of ν_{µ} and the appearance of ν_{e} events between the Near and Far detectors yields |Δm_{32}^{2}|=2.40_{-0.09}^{+0.08}(2.45_{-0.08}^{+0.07})×10^{-3} eV^{2} and sin^{2}θ_{23}=0.43_{-0.04}^{+0.20}(0.42_{-0.03}^{+0.07}) at 68% C.L. for normal (inverted) hierarchy.

2.
Phys Rev Lett ; 125(7): 071801, 2020 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32857527

RESUMO

Searches for electron antineutrino, muon neutrino, and muon antineutrino disappearance driven by sterile neutrino mixing have been carried out by the Daya Bay and MINOS+ collaborations. This Letter presents the combined results of these searches, along with exclusion results from the Bugey-3 reactor experiment, framed in a minimally extended four-neutrino scenario. Significantly improved constraints on the θ_{µe} mixing angle are derived that constitute the most constraining limits to date over five orders of magnitude in the mass-squared splitting Δm_{41}^{2}, excluding the 90% C.L. sterile-neutrino parameter space allowed by the LSND and MiniBooNE observations at 90% CL_{s} for Δm_{41}^{2}<13 eV^{2}. Furthermore, the LSND and MiniBooNE 99% C.L. allowed regions are excluded at 99% CL_{s} for Δm_{41}^{2}<1.6 eV^{2}.

3.
Phys Rev Lett ; 122(9): 091803, 2019 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-30932529

RESUMO

A search for mixing between active neutrinos and light sterile neutrinos has been performed by looking for muon neutrino disappearance in two detectors at baselines of 1.04 and 735 km, using a combined MINOS and MINOS+ exposure of 16.36×10^{20} protons on target. A simultaneous fit to the charged-current muon neutrino and neutral-current neutrino energy spectra in the two detectors yields no evidence for sterile neutrino mixing using a 3+1 model. The most stringent limit to date is set on the mixing parameter sin^{2}θ_{24} for most values of the sterile neutrino mass splitting Δm_{41}^{2}>10^{-4} eV^{2}.

4.
J Anim Sci ; 95(5): 2121-2132, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28726997

RESUMO

We conducted a study in which body composition, energy and protein requirements, and efficiency of MP and ME were determined in F1 Boer × Saanen goat kids of 5 to 25 kg BW by using the comparative slaughter technique. Two experiments were performed: Exp. 1 estimated the maintenance requirements of kids from 15 to 25 kg BW, and Exp. 2 estimated the gain requirements of kids from 5 to 25 kg BW. In Exp. 1, 28 intact male F1 Boer × Saanen goat kids were utilized, with 7 kids slaughtered (BW of 15.0 ± 0.35 kg) at the onset for estimation of initial body composition and the remaining 21 kids assigned to a randomized block design. Within each block, kids were subjected to 3 levels of feed intake treatments (ad libitum [100%] or restricted to 70% or 40% ad libitum). All kids in each block were slaughtered when the animals fed ad libitum reached 25 kg BW. The NE, ME for maintenance, and partial efficiency of use of ME for NE were 321.6 kJ/kg BW, 525.9 kJ/kg BW, and 0.61, respectively. The net protein and MP for maintenance were 2.43 g/kg of BW and 4.41 g/kg of BW, respectively; thus, the estimated partial efficiency of MP for maintenance was 0.55. In Exp. 2, 32 intact male F1 Boer × Saanen goat kids were distributed in a completely randomized design and slaughtered at 5.6 ± 0.85 kg BW ( = 6), 10.0 ± 0.35 kg BW ( = 6), 15.3 ± 0.52 kg BW ( = 7), 20.4 ± 0.66 kg BW ( = 6), and 25 ± 0.46 kg BW ( = 7). Body composition was then fitted to allometric equations. Body fat composition increased from 37 to 114 g/kg empty BW (EBW; < 0.001), and body protein composition decreased by 10% (from 203.2 to 180.6 g/kg EBW; < 0.001) when kids grew from 5 to 25 kg BW. The NE increased by approximately 60% (from 7.2 to 11.5 MJ/kg of empty BW gain [EWG]; < 0.001), and the net protein for gain decreased by 10% (from 186 to 166 g/kg of EWG; < 0.001). The partial efficiency of the utilization of ME to NE for growth was 0.32 ( < 0.0001), and the partial efficiencies of the utilization of ME for the synthesis of protein and fat were 0.19 and 0.59 ( < 0.011), respectively. These results demonstrate that the protein and energy maintenance requirements in young crossbred goat kids are greater than values reported previously in feeding system studies. In addition, their requirements for gain depend on body composition and are driven by efficiencies of deposition.


Assuntos
Ração Animal/análise , Composição Corporal , Metabolismo Energético , Cabras/fisiologia , Proteínas/metabolismo , Tecido Adiposo , Fenômenos Fisiológicos da Nutrição Animal , Animais , Peso Corporal , Dieta/veterinária , Cabras/crescimento & desenvolvimento , Masculino , Necessidades Nutricionais , Oligopeptídeos , Distribuição Aleatória
5.
Phys Rev Lett ; 117(15): 151803, 2016 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-27768323

RESUMO

We report results of a search for oscillations involving a light sterile neutrino over distances of 1.04 and 735 km in a ν_{µ}-dominated beam with a peak energy of 3 GeV. The data, from an exposure of 10.56×10^{20} protons on target, are analyzed using a phenomenological model with one sterile neutrino. We constrain the mixing parameters θ_{24} and Δm_{41}^{2} and set limits on parameters of the four-dimensional Pontecorvo-Maki-Nakagawa-Sakata matrix, |U_{µ4}|^{2} and |U_{τ4}|^{2}, under the assumption that mixing between ν_{e} and ν_{s} is negligible (|U_{e4}|^{2}=0). No evidence for ν_{µ}→ν_{s} transitions is found and we set a world-leading limit on θ_{24} for values of Δm_{41}^{2}≲1 eV^{2}.

6.
J Anim Sci ; 94(4): 1472-81, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27136006

RESUMO

We aimed to evaluate the expression of genes related to the regulation of muscle protein turnover in the longissimus dorsi (LD) muscle of Angus and Nellore bulls and to estimate the within-breed correlations of gene expression and performance traits. Thirteen genes related to the IGF-1 and myostatin pathways were studied. Thirteen animals, with an initial average BW of 381.2 ± 11.8 kg, from each breed were used in a completely randomized 2 × 2 factorial design (2 breeds and 2 feeding levels). The diet consisted of corn silage and a corn-soybean meal concentrate in a roughage-to-concentrate ratio of 30:70. Cattle were fed ad libitum (with 9 animals from each breed) or feed restricted (a 55% restriction of total DMI of ad libitum-fed animals, calculated as percentage of metabolic BW, with 4 animals of each breed). The experimental period lasted for 82 d and it was preceded by a 28-d adaptation period. The performance traits evaluated were slaughter body weight, total ADG (from d 1 to 82 of the trial), initial ADG (from d 1 to 41 of the trial), final ADG (from d 42 to 82 of the trial), total DMI (from d 1 to 82 of the trial), initial DMI (from d 1 to 41 of the trial), final DMI (from d 42 to 82 of the trial), HCW, LD weight (LDW), and rib eye area (REA). After slaughter, samples were taken from the LD muscle between the 12th and 13th ribs for gene expression analysis by quantitative reverse transcription PCR. There was no difference ( > 0.05) in the expression of any of the genes studied between ad libitum-fed Angus and ad libitum-fed Nellore, whereas feed restriction increased the expression of (; < 0.001), (; = 0.05), and (; = 0.04) and decreased the expression of ( < 0.01). The REA was negatively correlated to (; = 0.01), (; = 0.02), and ( = 0.05). The HCW was negatively correlated to ( = 0.01) and ( = 0.01) and tended to be negatively correlated to ( = 0.07), whereas the LDW tended to be negatively correlated to ( = 0.08). The genes , , and seem to be important for muscle growth and may be worthy of further investigation as future strategies for increasing muscle in livestock.


Assuntos
Composição Corporal/fisiologia , Bovinos/genética , Regulação da Expressão Gênica/fisiologia , Proteínas Musculares/metabolismo , Ração Animal/análise , Animais , Composição Corporal/genética , Peso Corporal , Bovinos/fisiologia , Dieta/veterinária , Fibras na Dieta/metabolismo , Comportamento Alimentar/fisiologia , Fator de Crescimento Insulin-Like I/metabolismo , Masculino , Proteínas Musculares/genética , Silagem/análise
7.
J Anim Sci ; 94(3): 1105-9, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27065272

RESUMO

The traditional techniques to measure heat production (HP) are calorimetry (direct and indirect) and comparative slaughter. Both methods are expensive and require extensive amounts of time and infrastructure. Infrared thermography (IRT) could be a faster and less expensive alternative to estimate cattle HP. The objective of this project was to evaluate the use of the IRT technique as an indicator of HP in cattle. A total of 24 bulls (12 Nellore and 12 Black Angus) with initial BW of 380 ± 7 kg were used. Initially, 4 animals of each breed were harvested (baseline animals) and simple regressions were developed for each breed from these baseline animals to estimate the initial chemical composition of the remaining bulls. Eight animals of each breed were fed a silage/concentrate diet for ad libitum intake in individual stalls. On the 25th, 50th, and 75th experimental day, infrared thermal images (Fluke Ti 55ft; Fluke Corporation) were taken of each animal's face to access skin and ocular surface temperatures. A metabolism trial was conducted to estimate the ME intake (MEI). After 84 experimental days, the cattle were harvested and retained energy (RE) and HP were calculated. The data were analyzed using the MIXED and REG procedures of SAS adopting a significance level of 0.05. Angus cattle had a greater daily MEI, HP, and skin and eye temperatures than Nellore. We found significant correlations ( ≤ 0.005) between daily HP and maximum ( = 0.65) and average skin temperatures ( = 0.65) and maximum ( = 0.65) and average ocular surface ( = 0.69) temperatures recorded on d 50. Infrared thermography has potential to be used to evaluate HP in cattle.


Assuntos
Bovinos/fisiologia , Metabolismo Energético/fisiologia , Termogênese , Termografia , Animais , Masculino
8.
J Anim Sci ; 94(12): 5414-5422, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28046161

RESUMO

The use of digital images could be a faster and cheaper alternative technique to assess BW, HCW, and body composition of beef cattle. The objective of this study was to develop equations to predict body and carcass weight and body fat content of young bulls using digital images obtained through a Microsoft Kinect device. Thirty-five bulls with an initial BW of 383 (±5.38) kg (20 Black Angus, 390 [±7.48] kg initial BW, and 15 Nellore, 377 [±8.66] kg initial BW) were used. The Kinect sensor, installed on the top of a cattle chute, was used to take infrared light-based depth videos, recorded before the slaughter. For each animal, a quality control was made, running and pausing the video at the moment that the animal was standing with its body and head in line. One frame from recorded videos was selected and used to analyze the following body measurements: chest width, thorax width, abdomen width, body length, dorsal height, and dorsal area. From these body measurements, 23 indexes were generated and tested as potential predictors. The BW and HCW were assessed with a digital scale, whereas empty body fat (EBF) was estimated through ground samples of all tissues. To better understand the relationship among the measurements, the correlations between final BW (488 [±10.4] kg), HCW (287 [±12.5] kg), EBF (14 [±0.610] % empty BW) content, body measurements (taken through digital images), and developed indexes were evaluated. The REG procedure was used to develop the regressions, and the important independent variables were identified using the options STEPWISE and Mallow's Cp in the SELECTION statement. Chest width was the trait most related to weights and the correlations between this measurement and BW and HCW were above 0.85. The analysis of linear regressions between observed and predicted values showed that all models pass through the origin and have a slope of unity (null hypothesis [H]: = 0 and = 1; ≥ 0.993). The models to estimate BW and HCW of Angus and Nellore presented between 0.69 and 0.84 ( < 0.001), whereas from equations to estimate the EBF were lower ( = 0.43-0.45; ≤ 0.006). Index I5 [(chest width) × body length], related to the animal volume, was significant in all models created to estimate BW and HCW, and it explained more than 70% of the variation. This study indicates that digital images taken through a Microsoft Kinect system have the potential to be used as a tool to estimate body and carcass weight of beef cattle.


Assuntos
Composição Corporal/fisiologia , Peso Corporal/fisiologia , Bovinos/fisiologia , Processamento de Imagem Assistida por Computador/métodos , Tecido Adiposo/fisiologia , Animais , Masculino
9.
Genet Mol Res ; 13(4): 9806-16, 2014 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-25501190

RESUMO

The aim of this study was to analyze the relationship between environmental and genetic values for milk production and type traits in Holstein cattle in Brazil. The genetic value of 65,383 animals for milk production and 53,626 for type classification were available. Socioeconomic and environmental data were obtained from the Brazilian Institute of Geography and Statistics, the Food and Agriculture Organization of the United Nations, the National Aeronautics and Space Administration, and the National Institute of Meteorology. Five to six clusters were generated for each of the groups of type traits and production levels. The relationships between these traits were assessed using the STEPDISC, DISCRIM and CANDISC procedures in SAS(®). Traits within the clusters behaved differently, but, in general, animals with lower genetic values were found in environments that were more stressful for animal production. These differences were mainly associated with temperature, humidity, precipitation and the Normalized Difference Vegetative Index. Genetic values for milk production showed best discrimination between different environments, while type traits showed poor discrimination, possibly because farmers mainly select for milk production. Environmental variations for genetic values in dairy cattle in Brazil should be further examined.


Assuntos
Cruzamento/estatística & dados numéricos , Indústria de Laticínios/estatística & dados numéricos , Fertilidade/genética , Lactação/genética , Característica Quantitativa Herdável , Animais , Brasil , Bovinos , Análise por Conglomerados , Meio Ambiente , Feminino , Interação Gene-Ambiente , Variação Genética , Masculino , Leite , Modelos Genéticos , Fenótipo , Seleção Genética
10.
Phys Rev Lett ; 112(19): 191801, 2014 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-24877929

RESUMO

We report on a new analysis of neutrino oscillations in MINOS using the complete set of accelerator and atmospheric data. The analysis combines the ν(µ) disappearance and ν(e) appearance data using the three-flavor formalism. We measure |Δm(32)(2)| = [2.28-2.46] × 10(-3) eV(2) (68% C.L.) and sin(2)θ(23) = 0.35-0.65 (90% C.L.) in the normal hierarchy, and |Δm(32)(2)| = [2.32-2.53] × 10(-3) eV(2) (68% C.L.) and sin(2)θ(23) = 0.34-0.67 (90% C.L.) in the inverted hierarchy. The data also constrain δ(CP), the θ(23} octant degeneracy and the mass hierarchy; we disfavor 36% (11%) of this three-parameter space at 68% (90%) C.L.

11.
Rev. bras. plantas med ; 16(3): 534-538, jul.-set. 2014. tab
Artigo em Inglês | LILACS | ID: lil-722273

RESUMO

The present study is pioneer in analyzing the chemical composition of the essential oil from aerial parts of Turnera subulata Sm. and evaluates their antibacterial activity against a panel of drug-resistant strains of Staphylococcus aureus. The aerial parts were kiln-dried and then powdered in mechanical mill, and was subjected to hydrodistillation in a Clevenger-type apparatus. The components were analyzed using a mass spectrometrycoupled gas chromatography (GC-MS), and the identification of substances was performed by comparison of the mass spectra obtained with the mass spectra of the database of the GC-MS and retention indices . The essential oil was evaluated using the method of broth dilution at concentrations ranging from 3.125µg/mL to 3200µg/mL. It was possible to identify 45 substances (92.1%) of the essential oils, and the major components were trans-caryophyllene (6.7%), citronellol (5.6%), sphatulenol (5.3%), α-cadinol (4.3%), n-tricosano (4.3%), geraniol (4.1%) and trans-geranilacetone (3.7%), n-pentacosano (3.5%), globulol (3.4%), caryophyllene oxide (3.2%). The essential oil of T. subulata Sm. showed effective antibacterial activity for the various strains of S. aureus tested, with the MIC values between 25 µg/mL and 1600 µg/mL. The study of the essential oil of Turnera subulata Sm. showed that it consists of a complex mixture of several classes of compounds having the sesquiterpenes as major constituents followed by monoterpenes, and showed an antibacterial activity significant front the strains tested.


O presente estudo é pioneiro em analisar a composição química dos óleos essenciais das partes aéreas de Turnera subulata Sm. e sua atividade antibacteriana frente à Staphylococcus aureus resistentes a antibióticos. As partes aéreas da planta foram secas em estufa, pulverizadas em moinho mecânico e submetidas à hidrodestilaçao em aparato tipo Clevenger. A composição dos óleos essenciais foi analisada por cromatografia gasosa acoplada a espectrometria de massas (CG-EM), e a identificação realizada por comparação dos espectros de massas com a biblioteca do CG-EM e índices de retenção. A atividade antimicrobiana do óleo essencial foi avaliada usando o método de diluição em caldo, em concentrações que variaram de 3.125µg/mL to 3200µg/mL. Foi possível identificar 45 substâncias (92,1%) do óleo essencial, sendo os componentes majoritários: trans-cariofileno (6,7%), citronelol (5,6%), espatulenol (5,3%), α-cadinol (4,3%), n-tricosano (4,3%), geraniol (4,1%) e trans-geranilacetona (3,7%), n-pentacosano (3,5%), globulol (3,4%) e óxido de cariofileno (3,2%). O óleo essencial de T. subulata Sm. mostrou atividade antibacteriana eficaz para as várias cepas de S. aureus testadas, com valores de CIM entre 25 µg/mL e 1600 µg/mL. O estudo do óleo essencial de Turnera subulata Sm. evidenciou sua complexa mistura, contendo várias classes de substâncias, tendo os sesquiterpenos como constituintes majoritários seguido dos monoterpenos, e mostrou significativa atividade antibacteriana frente as cepas testadas.


Assuntos
Infecções Estafilocócicas/tratamento farmacológico , Óleos Voláteis/química , Turnera/metabolismo , Espectrometria de Massas/instrumentação , Staphylococcus aureus/patogenicidade , Cromatografia Gasosa/instrumentação , Componentes Aéreos da Planta/metabolismo
12.
Phys Rev Lett ; 110(25): 251801, 2013 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-23829728

RESUMO

We report measurements of oscillation parameters from ν(µ) and ν(µ) disappearance using beam and atmospheric data from MINOS. The data comprise exposures of 10.71×10(20) protons on target in the ν(µ)-dominated beam, 3.36×10(20) protons on target in the ν(µ)-enhanced beam, and 37.88 kton yr of atmospheric neutrinos. Assuming identical ν and ν oscillation parameters, we measure |Δm2| = (2.41(-0.10)(+0.09))×10(-3) eV2 and sin2(2θ) = 0.950(-0.036)(+0.035). Allowing independent ν and ν oscillations, we measure antineutrino parameters of |Δm2| = (2.50(-0.25)(+0.23))×10(-3) eV2 and sin2(2θ) = 0.97(-0.08)(+0.03), with minimal change to the neutrino parameters.

13.
Phys Rev Lett ; 110(17): 171801, 2013 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-23679706

RESUMO

We report on ν(e) and ν(e) appearance in ν(µ) and ν(µ) beams using the full MINOS data sample. The comparison of these ν(e) and ν(e) appearance data at a 735 km baseline with θ13 measurements by reactor experiments probes δ, the θ23 octant degeneracy, and the mass hierarchy. This analysis is the first use of this technique and includes the first accelerator long-baseline search for ν(µ) → ν(e). Our data disfavor 31% (5%) of the three-parameter space defined by δ, the octant of the θ23, and the mass hierarchy at the 68% (90%) C.L. We measure a value of 2sin(2)(2θ13)sin(2)(θ23) that is consistent with reactor experiments.

14.
Phys Rev Lett ; 108(19): 191801, 2012 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-23003026

RESUMO

We report an improved measurement of ν(µ) disappearance over a distance of 735 km using the MINOS detectors and the Fermilab Main Injector neutrino beam in a ν(µ)-enhanced configuration. From a total exposure of 2.95×10(20) protons on target, of which 42% have not been previously analyzed, we make the most precise measurement of Δm2=[2.62(-0.28)(+0.31)(stat)±0.09(syst)]×10(-3) eV2 and constrain the ν(µ) mixing angle sin2(2θ)>0.75 (90% C.L.). These values are in agreement with Δm2 and sin2(2θ) measured for ν(µ), removing the tension reported in [P. Adamson et al. (MINOS), Phys. Rev. Lett. 107, 021801 (2011).].

15.
Phys Rev Lett ; 107(20): 201803, 2011 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-22181724

RESUMO

The KTeV E799 experiment has conducted a search for the rare decays, K(L)→π(0)π(0)µ(+)µ(-) and K(L)→π(0)π(0)X(0)→π(0)π(0)µ(+)µ(-), where the X(0) is a possible new neutral boson that was reported by the HyperCP experiment with a mass of (214.3 ± 0.5) MeV/c(2). We find no evidence for either decay. We obtain upper limits of Br(K(L)→π(0)π(0)X(0)→π(0)π(0)µ(+)µ(-)) < 1.0 × 10(-10) and Br(K(L)→π(0)π(0)µ(+)µ(-)) < 9.2 × 10(-11) at the 90% confidence level. This result rules out the pseudoscalar X(0) as an explanation of the HyperCP result under the scenario that the dsX(0) coupling is completely real.

16.
Phys Rev Lett ; 107(18): 181802, 2011 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-22107623

RESUMO

We report the results of a search for ν(e) appearance in a ν(µ) beam in the MINOS long-baseline neutrino experiment. With an improved analysis and an increased exposure of 8.2 × 10(20) protons on the NuMI target at Fermilab, we find that 2 sin(2) (θ(23))sin(2)(2θ(13))<0.12(0.20) at 90% confidence level for δ = 0 and the normal (inverted) neutrino mass hierarchy, with a best-fit of 2sin(2) (θ(23))sin(2)(2θ(13)) = 0.041(-0.031)(+0.047) (0.079(-0.053) (+0.071)). The θ(13) = 0 hypothesis is disfavored by the MINOS data at the 89% confidence level.

17.
Phys Rev Lett ; 107(1): 011802, 2011 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-21797535

RESUMO

Results are reported from a search for active to sterile neutrino oscillations in the MINOS long-baseline experiment, based on the observation of neutral-current neutrino interactions, from an exposure to the NuMI neutrino beam of 7.07×10(20) protons on target. A total of 802 neutral-current event candidates is observed in the Far Detector, compared to an expected number of 754 ± 28(stat) ± 37(syst) for oscillations among three active flavors. The fraction f(s) of disappearing ν(µ) that may transition to ν(s) is found to be less than 22% at the 90% C.L.

18.
Phys Rev Lett ; 107(2): 021801, 2011 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-21797594

RESUMO

This Letter reports the first direct observation of muon antineutrino disappearance. The MINOS experiment has taken data with an accelerator beam optimized for ν(µ) production, accumulating an exposure of 1.71 × 10²° protons on target. In the Far Detector, 97 charged current ν(µ) events are observed. The no-oscillation hypothesis predicts 156 events and is excluded at 6.3σ. The best fit to oscillation yields |Δm²| = [3.36(-0.40)(+0.46)(stat) ± 0.06(syst)] × 10⁻³ eV², sin²(2θ) = 0.86(-0.12)(+0.11)(stat) ± 0.01(syst). The MINOS ν(µ) and ν(µ) measurements are consistent at the 2.0% confidence level, assuming identical underlying oscillation parameters.

19.
Phys Rev Lett ; 106(18): 181801, 2011 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-21635083

RESUMO

Measurements of neutrino oscillations using the disappearance of muon neutrinos from the Fermilab NuMI neutrino beam as observed by the two MINOS detectors are reported. New analysis methods have been applied to an enlarged data sample from an exposure of 7.25×10(20) protons on target. A fit to neutrino oscillations yields values of |Δm(2)|=(2.32(-0.08)(+0.12))×10(-3) eV(2) for the atmospheric mass splitting and sin(2)(2θ)>0.90 (90% C.L.) for the mixing angle. Pure neutrino decay and quantum decoherence hypotheses are excluded at 7 and 9 standard deviations, respectively.

20.
Phys Rev Lett ; 105(15): 151601, 2010 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-21230890

RESUMO

We searched for a sidereal modulation in the MINOS far detector neutrino rate. Such a signal would be a consequence of Lorentz and CPT violation as described by the standard-model extension framework. It also would be the first detection of a perturbative effect to conventional neutrino mass oscillations. We found no evidence for this sidereal signature, and the upper limits placed on the magnitudes of the Lorentz and CPT violating coefficients describing the theory are an improvement by factors of 20-510 over the current best limits found by using the MINOS near detector.

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