[en] The Double Chooz experiment is a reactor antineutrino disappearance experiment located in Chooz, France. It was designed to measure the neutrino mixing angle θ${}_{13}$. The experiment is composed of two liquid scintillator detectors of almost identical design that were able to identify electron antineutrinos from the two Chooz B reactor cores by the unique signal of the inverse beta decay. The far detector at an average baseline of 1050 m from the two reactor cores was in operation from April 2011 to the beginning of 2018. The near detector at an average baseline of 400 m has been operating from the beginning of 2015 to the beginning of 2018. A neutrino oscillation analysis can be setup independently from any theoretical model of the reactor neutrino flux utilizing the different baselines of near and far detector relying only on the comparison of near and far detector data. In doing so, all correlated systematics cancel and the analysis is protected against potential bias due to a mismatch of reactor neutrino prediction and data. Apart from its original design goal to measure θ${}_{13}$, Double Chooz is sensitive to so called light sterile neutrinos. Sterile neutrinos are neutrino states that do not take part in the weak interaction but may lead to additional disappearance of the known neutrino states, if they mix with the latter. That mixing is described by additional neutrino squared mass differences and mixing angles. The 3+1 model assumes one additional sterile state. Here, Double Chooz is sensitive to the new mixing angle θ${}_{14}$ depending on the new squared mass difference Δm${}_{41}^2$ if it is in the range of 0.003 eV${}^2$ ≲ Δm${}_{41}^2$ ≲ 0.3 eV${}^2$. This work presents the analysis of Double Chooz data with respect to sterile neutrinos. A Poissonian likelihood fit approach not relying on reactor model predictions is used. It is found that the Double Chooz data is with a p-value of 24.7% ± 2.2% consistent with the no-sterile (i.e. θ${}_{14}$=0) hypothesis. The upper limit on sin${}^2$2θ${}_{14}$ at 95% confidence level is given as a function of Δm${}_{41}^2$.

[en] Double Chooz is a reactor antineutrino disappearance experiment located in Chooz, France, to measure the neutrino mixing angle ${\mathrm{\theta <!--\; ??\; -->}}_{13}$. By detecting the unique inverse beta decay (IBD) prompt-delayed signal antineutrinos can be precisely identified. The experiment consists of two liquid scintillator detectors of identical design; a far detector at a distance of about 1 km is operating since 2011; a near detector at a distance of about 400 m is operating since begin 2015. This double-detector setup with iso-flux configuration allows to fit the far detector data to the near detector data without relying on the reactor neutrino flux prediction where systematic uncertainties are suppressed to per mill level. Statistical uncertainties are reduced by not only using the delayed signal of neutron capture on Gadolinium but adding neutron captures on Hydrogen yielding a statistics increase of more than a factor of two. Apart from a precise measurement of ${\mathrm{\theta <!--\; ??\; -->}}_{13}$, the combination of the two detectors also offers sensitivity to sterile neutrino mixing parameters. Sterile neutrinos are neutrino mass states not taking part in weak interactions, but may mix with known neutrino states. This induces additional mixing angles and mass differences. This contribution will present the latest ${\mathrm{\theta <!--\; ??\; -->}}_{13}$ results of the Double Chooz collaboration as well as the results of the sterile analysis.

[en] The Double Chooz experiment is a reactor neutrino disappearance experiment located at the Chooz nuclear power plant, France. It measures the electron-antineutrino flux of the two nuclear reactors with two detectors of identical design: A far detector at a distance of about 1 km and a near detector at a distance of about 400 m. The detectors have been operating from 2011 (far) and 2014 (near) till end of 2017. The combination of the two detectors offers sensitivity to sterile neutrino mixing parameters. Sterile neutrinos are neutrino mass states not taking part in weak interactions, but may mix with known neutrino states. This induces additional mixing angles and mass differences where Double Chooz is sensitive to the new mixing angle ${\mathrm{\theta <!--\; ??\; -->}}_{14}$. This talk describes the search for sterile neutrinos and its results.

[en] The IceCube Neutrino Observatory is a 1 km³ Cherenkov detector located at the geographic South Pole. It records atmospheric muon neutrinos with unprecedented statistics of several ten thousand events per year on analysis level and has proven to be suitable for the observation of muon disappearance due to neutrino oscillations. If additional sterile neutrino states exist with mass differences in the order of a few eV, a disappearance of muon neutrinos in the energy range of a few TeV will occur due to matter effects. The survival probability depends on the energy and the path of the neutrino through the Earth and thus its zenith angle. The excellent statistics in the relevant range of energies and baselines make IceCube an ideal tool for testing models of one or more sterile neutrinos. This talk gives an overview of different oscillation signatures, introduces a two-dimensional Likelihood method, and shows how IceCube can be sensitive to these oscillation effects, based on data taken with its 59-string configuration.

[en] The Double Chooz experiment is a reactor neutrino disappearance experiment for the precise measurement of the neutrino mixing angle ${\mathrm{\theta <!--\; ??\; -->}}_{13}$. Two identical liquid scintillator detectors with baselines of 1050 m and 400 m are installed at the nuclear power plant in Chooz, France. These are measuring the flux of antineutrinos from two reactor cores utilizing the signature of the inverse beta decay (IBD). To explain the deviation from the measured data to the theoretically predicted neutrino flux, one possibility would be non weakly-interacting sterile neutrinos. A study of the sensitivity to a scenarion with two additional sterile neutrinos will be presented.

[en] The Double Chooz experiment is a reactor neutrino disappearance experiment located at the Chooz nuclear power plant, France. It measures the electron-antineutrino flux of the two nuclear reactors with two detectors of identical design. A far detector at a distance of about 1 km is operating since 2011; a near detector at a distance of about 400 m is operating since the end of 2014. The combination of the two detectors offers sensitivity to sterile neutrino mixing parameters. Sterile neutrinos are neutrino mass states not taking part in weak interactions, but may mix with known neutrino states. This induces additional mixing angles and mass differences. This talk describes the search for sterile neutrinos and the sensitivity of Double Chooz to the mixing angle θ_1_4.

[en] The Double Chooz experiment is a reactor neutrino experiment with the purpose of a precise measurement of the neutrino mixing angle θ_1_3. The setup consists of two identical liquid scintillator detectors at an average baseline of 400 m and 1 km to two nuclear reactor cores in Chooz, France. The neutrinos are detected by the signature of the inverse beta decay, which consists of a positron signal and a delayed neutron capture signal. From the positron measurement the neutrino energy is extracted. Neutrons are captured either by gadolinium or hydrogen in the scintillator. Due to different capture energies, two independent data samples are obtained. This presentation describes the determination of the neutrino mixing angle θ_1_3 using a likelihood fit approach of hydrogen capture data.

[en] The IceCube Neutrino Observatory, located at the Geographic South Pole, measures an all-sky atmospheric neutrino flux. These neutrinos are created in cosmic-ray-induced air showers and their production rate depends on local atmospheric conditions, causing neutrino rate changes throughout the local seasons. Five years of neutrino data from IceCube and temperature data from NASA's atmosphere-observing Aqua-Satellite are used to measure the correlation coefficient of relative neutrino rate change and relative temperature change. This correlation coefficient can be used to constrain neutrino production yields of pions and kaons. We present method and results of calculating the neutrino-temperature correlation coefficient and further outlooks.

[en] The Double Chooz experiment is a reactor neutrino disappearance experiment located at the nuclear power plant in Chooz, France. The aim of the Double Chooz experiment is the precise measurement of the neutrino mixing angle θ_1_3, a neutrino oscillation parameter. The experiment consists of two identical liquid scintillator detectors and measures the electron-antineutrino flux of the two nuclear reactors. The 1 km distant far detector started operation in 2011. The 400 m distant near detector started operation in 2015. The reactor neutrinos are detected by the signature of an inverse beta decay (IBD). The neutrino energy spectrum is extracted from the spectrum of the IBD-produced positrons. The IBD-produced neutrons can be captured by Gadolinium or Hydrogen, which provides two independent data samples. Both samples allow the utilisation of the neutrino rate and energy spectral shape information in a combined fit. This contribution presents the first oscillation results derived from the full two-detector setup.

[en] The Double Chooz experiment is a reactor anti-neutrino experiment for the purpose of a precise measurement of the neutrino mixing angle θ₁₃. The experimental setup consists of two identical liquid scintillator detectors at an average baseline of about 400 m and 1 km to two reactor cores at the nuclear power plant in Chooz, France. The neutrinos are detected by measuring the signature of the inverse beta decay (IBD), which consists of a prompt positron signal and a delayed neutron capture signal. By performing a simultaneous likelihood fit and taking into account the detector neutrino rates, the energy spectral shape and all relevant backgrounds, the neutrino mixing angle θ₁₃ can be obtained. In this talk the method, design, performance and optimisation of such a likelihood fit are presented. Furthermore a crosscheck for the latest final fit results are shown.