Explore the vast range of titles available.

In 1956 Reines & Cowan discovered the neutrino using a liquid scintillator detector. The neutrinos interacted with the scintillator, producing light that propagated across transparent volumes to surrounding photo-sensors. This approach has remained one of the most widespread and successful neutrino detection technologies used since. This article introduces a concept that breaks with the conventional paradigm of transparency by confining and collecting light near its creation point with an opaque scintillator and a dense array of optical fibres. This technique, called LiquidO, can provide high-resolution imaging to enable efficient identification of individual particles event-by-event. A natural affinity for adding dopants at high concentrations is provided by the use of an opaque medium. With these and other capabilities, the potential of our detector concept to unlock opportunities in neutrino physics is presented here, alongside the results of the first experimental validation. Liquid scintillator detectors have been used to study neutrinos ever since their discovery in 1956. The authors introduce an opaque scintillator detector concept for future neutrino experiments with increased capacity for particle identification and a natural affinity for doping.

Using data from the NEMO-3 experiment, we have measured the two-neutrino double beta decay (\\[2\\nu \\beta \\beta \\]) half-life of \\[^{82}\\]Se as \\[T_{\\smash {1/2}}^{2\\nu } \\!=\\! \\left[ 9.39 \\pm 0.17\\left( \\text{ stat }\\right) \\pm 0.58\\left( \\text{ syst }\\right) \\right] \\times 10^{19}\\] y under the single-state dominance hypothesis for this nuclear transition. The corresponding nuclear matrix element is \\[\\left| M^{2\\nu }\\right| = 0.0498 \\pm 0.0016\\]. In addition, a search for neutrinoless double beta decay (\\[0\\nu \\beta \\beta \\]) using 0.93 kg of \\[^{82}\\]Se observed for a total of 5.25 y has been conducted and no evidence for a signal has been found. The resulting half-life limit of \\[T_{1/2}^{0\\nu } > 2.5 \\times 10^{23} \\,\\text{ y } \\,(90\\%\\,\\text{ C.L. })\\] for the light neutrino exchange mechanism leads to a constraint on the effective Majorana neutrino mass of \\[\\langle m_{\\nu } \\rangle < \\left( 1.2{-}3.0\\right) \\,\\text{ eV }\\], where the range reflects \\[0\\nu \\beta \\beta \\] nuclear matrix element values from different calculations. Furthermore, constraints on lepton number violating parameters for other \\[0\\nu \\beta \\beta \\] mechanisms, such as right-handed currents, majoron emission and R-parity violating supersymmetry modes have been set.

The full data set of the NEMO-3 experiment has been used to measure the half-life of the two-neutrino double beta decay of \\[^{100}\\]Mo to the ground state of \\[^{100}\\]Ru, \\[T_{1/2} = \\left[ 6.81 \\pm 0.01\\,\\left( \\text{ stat }\\right) ^{+0.38}_{-0.40}\\,\\left( \\text{ syst }\\right) \\right] \\times 10^{18}\\] year. The two-electron energy sum, single electron energy spectra and distribution of the angle between the electrons are presented with an unprecedented statistics of \\[5\\times 10^5\\] events and a signal-to-background ratio of \\[\\sim \\] 80. Clear evidence for the Single State Dominance model is found for this nuclear transition. Limits on Majoron emitting neutrinoless double beta decay modes with spectral indices of \\[\\mathrm{n}=2,3,7\\], as well as constraints on Lorentz invariance violation and on the bosonic neutrino contribution to the two-neutrino double beta decay mode are obtained.

The manner in which leeches are maintained before they are used for therapy has not been studied as a factor contributing to nosocomial infections. A 5-year retrospective survey of Aeromonas hydrophila nosocomial infections at a hospital in Marseille, France, revealed infections in 5 (4.1%) of an estimated 122 patients treated with leeches in the Hand Surgery Unit and 2 (2.4%) of an estimated 85 patients treated with leeches in other hospital units. The retrospective survey showed that the Hand Surgery Unit was the only unit that had its own aquarium for maintaining leeches; this aquarium was filled with tap water contaminated with Aeromonas species and was not regularly disinfected or cleaned. Leeches used in other units were maintained in noncarbonated water in a transport device. Use of leeches kept in aquariums that are filled with tap water and not disinfected or cleaned regularly may be linked to A. hydrophila infections.

The possibility to probe new physics scenarios of light Majorana neutrino exchange and right-handed currents at the planned next generation neutrinoless double β decay experiment SuperNEMO is discussed. Its ability to study different isotopes and track the outgoing electrons provides the means to discriminate different underlying mechanisms for the neutrinoless double β decay by measuring the decay half-life and the electron angular and energy distributions.

The NEMO-3 results for the double- β decay of 150 Nd to the 0 1 + and 2 1 + excited states of 150 Sm are reported. The data recorded during 5.25 year with 36.6 g of the isotope 150 Nd are used in the analysis. The signal of the 2 ν β β transition to the 0 1 + excited state is detected with a statistical significance exceeding 5 σ . The half-life is measured to be T 1 / 2 2 ν β β ( 0 1 + ) = 1 . 11 - 0.14 + 0.19 stat - 0.15 + 0.17 syst × 10 20  year, which is the most precise value that has been measured to date. 90% confidence-level limits are set for the other decay modes. For the 2 ν β β decay to the 2 1 + level the limit is T 1 / 2 2 ν β β ( 2 1 + ) > 2.42 × 10 20 year . The limits on the 0 ν β β decay to the 0 1 + and 2 1 + levels of 150 Sm are significantly improved to T 1 / 2 0 ν β β ( 0 1 + ) > 1.36 × 10 22 year and T 1 / 2 0 ν β β ( 2 1 + ) > 1.26 × 10 22 year .

The NEMO-3 results for the double-$$\\beta $$β decay of$$^{150}$$150 Nd to the 0$$^+_1$$1 + and 2$$^+_1$$1 + excited states of$$^{150}$$150 Sm are reported. The data recorded during 5.25 year with 36.6 g of the isotope$$^{150}$$150 Nd are used in the analysis. The signal of the$$2\\nu \\beta \\beta $$2 ν β β transition to the 0$$^+_1$$1 + excited state is detected with a statistical significance exceeding 5$$\\sigma $$σ . The half-life is measured to be$$T_{1/2}^{2\\nu \\beta \\beta }(0^+_1) = \\left[ 1.11 ^{+0.19}_{-0.14} \\,\\left( \\hbox {stat}\\right) ^{+0.17}_{-0.15}\\,\\left( \\hbox {syst}\\right) \\right] \\times 10^{20}$$T 1 / 2 2 ν β β ( 0 1 + ) = 1 . 11 - 0.14 + 0.19 stat - 0.15 + 0.17 syst × 10 20  year, which is the most precise value that has been measured to date. 90% confidence-level limits are set for the other decay modes. For the$$2\\nu \\beta \\beta $$2 ν β β decay to the 2$$^+_1$$1 + level the limit is$$T^{2\\nu \\beta \\beta }_{1/2}(2^+_1) > 2.42 \\times 10^{20}~\\hbox {year}$$T 1 / 2 2 ν β β ( 2 1 + ) > 2.42 × 10 20 year . The limits on the$$0\\nu \\beta \\beta $$0 ν β β decay to the 0$$^+_1$$1 + and 2$$^+_1$$1 + levels of$$^{150}$$150 Sm are significantly improved to$$T_{1/2}^{0\\nu \\beta \\beta }(0^+_1) > 1.36 \\times 10^{22}~\\hbox {year}$$T 1 / 2 0 ν β β ( 0 1 + ) > 1.36 × 10 22 year and$$T_{1/2}^{0\\nu \\beta \\beta }(2^+_1) > 1.26 \\times 10^{22}~\\hbox {year}$$T 1 / 2 0 ν β β ( 2 1 + ) > 1.26 × 10 22 year .

The NEMO-3 results for the double- β decay of¹⁵⁰ Nd to the 0 ⁺₁and 2 ⁺₁excited states of¹⁵⁰ Sm are reported. The data recorded during 5.25 year with 36.6 g of the isotope¹⁵⁰ Nd are used in the analysis. The signal of the2ν β β transition to the 0 ⁺₁excited state is detected with a statistical significance exceeding 5 σ . The half-life is measured to beT_(1/2)^(2ν β β)(0⁺₁) = \\left[ 1.11 ^(+0.19)_(-0.14) \\left( \\hbox stat\\right) ^(+0.17)_(-0.15) \\left( \\hbox syst\\right) \\right] × 10²⁰  year, which is the most precise value that has been measured to date. 90% confidence-level limits are set for the other decay modes. For the2ν β β decay to the 2 ⁺₁level the limit isT^(2ν β β)_(1/2)(2⁺₁) > 2.42 × 10²⁰ \\hbox year . The limits on the0ν β β decay to the 0 ⁺₁and 2 ⁺₁levels of¹⁵⁰ Sm are significantly improved toT_(1/2)^(0ν β β)(0⁺₁) > 1.36 × 10²² \\hbox yearandT_(1/2)^(0ν β β)(2⁺₁) > 1.26 × 10²² \\hbox year .

Abstract The NEMO-3 results for the double-β β decay of¹⁵⁰150 Nd to the 0⁺₁1 + and 2⁺₁1 + excited states of¹⁵⁰150 Sm are reported. The data recorded during 5.25 year with 36.6 g of the isotope¹⁵⁰150 Nd are used in the analysis. The signal of the2ν β β 2 ν β β transition to the 0⁺₁1 + excited state is detected with a statistical significance exceeding 5σ σ . The half-life is measured to beT_(1/2)^(2ν β β)(0⁺₁) = \\left[ 1.11 ^(+0.19)_(-0.14) \\left( \\hbox stat\\right) ^(+0.17)_(-0.15) \\left( \\hbox syst\\right) \\right] × 10²⁰T 1 / 2 2 ν β β ( 0 1 + ) = 1 . 11 - 0.14 + 0.19 stat - 0.15 + 0.17 syst × 10 20  year, which is the most precise value that has been measured to date. 90% confidence-level limits are set for the other decay modes. For the2ν β β 2 ν β β decay to the 2⁺₁1 + level the limit isT^(2ν β β)_(1/2)(2⁺₁) > 2.42 × 10²⁰ \\hbox yearT 1 / 2 2 ν β β ( 2 1 + ) > 2.42 × 10 20 year . The limits on the0ν β β 0 ν β β decay to the 0⁺₁1 + and 2⁺₁1 + levels of¹⁵⁰150 Sm are significantly improved toT_(1/2)^(0ν β β)(0⁺₁) > 1.36 × 10²² \\hbox yearT 1 / 2 0 ν β β ( 0 1 + ) > 1.36 × 10 22 year andT_(1/2)^(0ν β β)(2⁺₁) > 1.26 × 10²² \\hbox yearT 1 / 2 0 ν β β ( 2 1 + ) > 1.26 × 10 22 year .