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Multiple-channel ultra-violet absorbance detector for two-dimensional chromatographic separations
Not Available
Search for WH production with a light Higgs boson decaying to prompt electron-jets in proton-proton collisions at root s=7 TeV with the ATLAS detector
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Exploring ν signals in dark matter detectors
We investigate standard and non-standard solar neutrino signals in direct dark matter detection experiments. It is well known that even without new physics, scattering of solar neutrinos on nuclei or electrons is an irreducible background for direct dark matter searches, once these experiments reach the ton scale. Here, we entertain the possibility that neutrino interactions are enhanced by new physics, such as new light force carriers (for instance a ''dark photon'') or neutrino magnetic moments. We consider models with only the three standard neutrino flavors, as well as scenarios with extra sterile neutrinos. We find that low-energy neutrino-electron and neutrino-nucleus scattering rates can be enhanced by several orders of magnitude, potentially enough to explain the event excesses observed in CoGeNT and CRESST. We also investigate temporal modulation in these neutrino signals, which can arise from geometric effects, oscillation physics, non-standard neutrino energy loss, and direction-dependent detection efficiencies. We emphasize that, in addition to providing potential explanations for existing signals, models featuring new physics in the neutrino sector can also be very relevant to future dark matter searches, where, on the one hand, they can be probed and constrained, but on the other hand, their signatures could also be confused with dark matter signals.
Gamma-ray bounds from EAS detectors and heavy decaying dark matter constraints
The very high energy Galactic γ-ray sky is partially opaque in the (0.1–10) PeV energy range. In the light of the recently detected high energy neutrino flux by IceCube, a comparable very high energy γ-ray flux is expected in any scenario with a sizable Galactic contribution to the neutrino flux. Here we elaborate on the peculiar energy and anisotropy features imposed upon these very high energy γ-rays by the absorption on the cosmic microwave background photons and Galactic interstellar light. As a notable application of our considerations, we study the prospects of probing the PeV-scale decaying DM scenario, proposed as a possible source of IceCube neutrinos, by extensive air shower (EAS) cosmic ray experiments. In particular, we show that anisotropy measurements at EAS experiments are already sensitive to τ{sub DM}∼O(10{sup 27}) s and future measurements, using better gamma/hadron separation, can improve the limit significantly.
Improved limits on dark matter annihilation in the Sun with the 79-string IceCube detector and implications for supersymmetry
We present an improved event-level likelihood formalism for including neutrino telescope data in global fits to new physics. We derive limits on spin-dependent dark matter-proton scattering by employing the new formalism in a re-analysis of data from the 79-string IceCube search for dark matter annihilation in the Sun, including explicit energy information for each event. The new analysis excludes a number of models in the weak-scale minimal supersymmetric standard model (MSSM) for the first time. This work is accompanied by the public release of the 79-string IceCube data, as well as an associated computer code for applying the new likelihood to arbitrary dark matter models.
A High-Granularity Timing Detector (HGTD) for the Phase-II upgrade of the ATLAS detector
Not provided.
Dijet azimuthal correlations and conditional yields in pp and p plus Pb collisions ats root S-NN=5.02 TeV with the ATLAS detector
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Measurement of the azimuthal anisotropy of charged-particle production in Xe plus Xe collisions at root S-NN=5.44 TeV with the ATLAS detector
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Measurement of event-plane correlations in s NN = 2.76 TeV lead-lead collisions with the ATLAS detector
A measurement of event-plane correlations involving two or three event planes of different order is presented as a function of centrality for 7 μb -1 Pb+Pb collision data at s NN = 2.76 TeV, recorded by the ATLAS experiment at the Large Hadron Collider. Fourteen correlators are measured using a standard event-plane method and a scalar-product method, and the latter method is found to give a systematically larger correlation signal. Several different trends in the centrality dependence of these correlators are observed. These trends are not reproduced by predictions based on the Glauber model, which includes only the correlations from the collision geometry in the initial state. Calculations that include the final-state collective dynamics are able to describe qualitatively, and in some cases also quantitatively, the centrality dependence of the measured correlators. These observations suggest that both the fluctuations in the initial geometry and the nonlinear mixing between different harmonics in the final state are important for creating these correlations in momentum space.
New measurement of the rare decay η → π 0 γ γ with the Crystal Ball/TAPS detectors at the Mainz Microtron
Not Available
Measurement of the correlation between flow harmonics of different order in lead-lead collisions at s NN = 2.76 TeV with the ATLAS detector
Not Available
Z boson production in p plus Pb collisions at root S-NN=5.02 TeV measured with the ATLAS detector
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Centrality, rapidity, and transverse momentum dependence of isolated prompt photon production in lead-lead collisions at root S-NN=2.76 TeV measured with the ATLAS detector
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Measurement of forward-backward multiplicity correlations in lead-lead, proton-lead, and proton-proton collisions with the ATLAS detector
Two-particle pseudorapidity correlations are measured in √ s NN = 2.76TeV Pb + Pb, √ s NN = 5.02TeV p + Pb, and √s = 13 TeV pp collisions at the Large Hadron Collider (LHC), with total integrated luminosities of approximately 7μb –1 , 28 nb –1 , and 65 nb –1 , respectively. The correlation function C N (η 1 ,η 2 ) is measured as a function of event multiplicity using charged particles in the pseudorapidity range |η| < 2.4. The correlation function contains a significant short-range component, which is estimated and subtracted. After removal of the short-range component, the shape of the correlation function is described approximately by 1 + < a2 1 > 1/2 η 1 η 2 in all collision systems over the full multiplicity range. The values of < a 2 1 > 1/2 are consistent for the opposite-charge pairs and same-charge pairs, and for the three collision systems at similar multiplicity. The values of < a 2 1 > 1/2 and the magnitude of the short-range component both follow a power-law dependence on the event multiplicity. Here, the short-range component in p + Pb collisions, after symmetrizing the proton and lead directions, is found to be smaller at a given η than in pp collisions with comparable multiplicity.