ANTARES Collaboration(Adrian-Martinez, S. et al), Barrios-Marti, J., Bigongiari, C., Emanuele, U., Gomez-Gonzalez, J. P., Hernandez-Rey, J. J., et al. (2014). A search for neutrino emission from the Fermi bubbles with the ANTARES telescope. Eur. Phys. J. C, 74(2), 2701–7pp.
Abstract: Analysis of the Fermi-LAT data has revealed two extended structures above and below the Galactic Centre emitting gamma rays with a hard spectrum, the so-called Fermi bubbles. Hadronic models attempting to explain the origin of the Fermi bubbles predict the emission of high-energy neutrinos and gamma rays with similar fluxes. The ANTARES detector, a neutrino telescope located in the Mediterranean Sea, has a good visibility to the Fermi bubble regions. Using data collected from 2008 to 2011 no statistically significant excess of events is observed and therefore upper limits on the neutrino flux in TeV range from the Fermi bubbles are derived for various assumed energy cutoffs of the source.
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Bout, R., Busto, J., Cecchini, V., Charpentier, P., Chapellier, M., Dastgheibi-Fard, A., et al. (2024). Perspectives of a single-anode cylindrical chamber operating in ionization mode and high gas pressure. Eur. Phys. J. C, 84(5), 512–14pp.
Abstract: As part of the R2D2 (Rare Decays with Radial Detector) R &D, the use of a gas detector with a spherical or cylindrical cathode, equipped with a single anode and operating at high pressure, was studied for the search of rare phenomena such as neutrinoless double-beta decay. The presented measurements were obtained with a cylindrical detector, covering gas pressures ranging from 1 to 10 bar in argon and 1 to 6 bar in xenon, using both a point-like source of 210 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$<^>{210} $$\end{document} Po (5.3 MeV alpha \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\alpha $$\end{document} ) and a diffuse source of 222 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$<^>{222}$$\end{document} Rn (5.5 MeV alpha \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\alpha $$\end{document} ). Analysis and interpretation of the data were developed using the anodic current waveform. Similar detection performances were achieved with both gases, and comparable energy resolutions were measured with both sources. As long as the purity of the gas was sufficient, no significant degradation of the measured energy was observed by increasing the pressure. At the highest operating pressure, an energy resolution better than 1.5% full-width at half-maximum (FWHM) was obtained for both gaseous media, although optimal noise conditions were not reached.
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LHCb Collaboration(Aaij, R. et al), Garcia Martin, L. M., Henry, L., Martinez-Vidal, F., Oyanguren, A., Remon Alepuz, C., et al. (2019). Measurements of CP asymmetries in charmless four-body Lambda(0)(b) and Xi(0)(b) decays. Eur. Phys. J. C, 79(9), 745–19pp.
Abstract: Asearch for CP violation in charmless four-body decays of Lambda(0)(b) and Xi(0)(b) baryons with a proton and three charged mesons in the final state is performed. To cancel out production and detection charge-asymmetry effects, the search is carried out by measuring the difference between the CP asymmetries in a charmless decay and in a decay with an intermediate charmed baryon with the same particles in the final state. The data sample used was recorded in 2011 and 2012 with the LHCb detector and corresponds to an integrated luminosity of 3 fb(-1). A total of 18 CP asymmetries are considered, either accounting for the full phase space of the decays or exploring specific regions of the decay kinematics. No significant CP-violation effect is observed in any of the measurements.
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ATLAS Collaboration(Aad, G. et al), Alvarez Piqueras, D., Cabrera Urban, S., Castillo Gimenez, V., Costa, M. J., Fernandez Martinez, P., et al. (2015). Search for heavy long-lived multi-charged particles in pp collisions at root s=8 TeV using the ATLAS detector. Eur. Phys. J. C, 75(8), 362–23pp.
Abstract: Asearch for heavy long-lived multi-charged particles is performed using the ATLAS detector at the LHC. Data collected in 2012 at root s = 8TeV from pp collisions corresponding to an integrated luminosity of 20.3 fb(-1) are examined. Particles producing anomalously high ionisation, consistent with long-livedmassive particleswith electric charges from vertical bar q vertical bar = 2e to vertical bar q vertical bar = 6e are searched for. No signal candidate events are observed, and 95% confidence level crosssection upper limits are interpreted as lower mass limits for a Drell-Yan production model. The mass limits range between 660 and 785 GeV.
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ATLAS Collaboration(Aad, G. et al), Amos, K. R., Aparisi Pozo, J. A., Bailey, A. J., Bouchhar, N., Cabrera Urban, S., et al. (2024). Search for top-philic heavy resonances in pp collisions at √s=13 TeV with the ATLAS detector. Eur. Phys. J. C, 84(2), 157–32pp.
Abstract: Asearch for the associated production of a heavy resonance with a top-quark or a top-antitop-quark pair, and decaying into a t (t) over bar pair is presented. The search uses the vdata recorded by the ATLAS detector in pp collisions at root s = 13 TeV at the Large Hadron Collider during the years 2015-2018, corresponding to an integrated luminosity of 139 fb(-1). Events containing exactly one electron ormuon are selected. The two hadronically decaying top quarks from the resonance decay are reconstructed using jets clustered with a large radius parameter of R = 1. The invariant mass spectrum of the two top quark candidates is used to search for a resonance signal in the range of 1.0 TeV to 3.2 TeV. The presence of a signal is examined using an approach with minimal model dependence followed by a model-dependent interpretation. No significant excess is observed over the background expectation. Upper limits on the production cross section times branching ratio at 95% confidence level are provided for a heavy Z' boson based on a simplified model, for Z' mass between 1.0 TeV and 3.0 TeV. The observed (expected) limits range from 21 (14) fb to 119 (86) fb depending on the choice of model parameters.
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