137 research outputs found

    Becoming a (green) identity entrepreneur: learning to negotiate situated identities to nurture community environmental practice

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    This paper explores the relationship between ‘green’ identity and community environmental practice. It focuses on the ways in which professional community development facilitators and lead members of community groups attempt to actively shape how environmental projects are locally received. Drawing principally on identity, social sustainability and social practice theory scholarship, it reviews the often very personal and place-specific ways in which appeals to green identity are variously understood and applied, or are actively avoided, by community group leaders. Individuals who have become skilful in negotiating and influencing the presentation of environmental projects to the local community are understood here as (green) identity entrepreneurs. Arguably, it is the situated entrepreneurial skilfulness of lead individuals in negotiating the multiple and evolving (green) identities circulating through any one project, which plays a significant part in determining its subsequent impact and longevity. In understanding the contribution of (green) identity entrepreneurship, however, its relational association with everyday practices, routines and meanings of community and place is brought to the fore. The paper also considers how divergent external interpretations of what constitutes legitimate environmental practice at a local level further shape project identity. The discussion is informed by evidence drawn from a qualitative study of seventeen community groups and seven professional environmental support officers participating in a Welsh Government led programme aimed at facilitating 'community action on climate change'

    Reconstruction of primary vertices at the ATLAS experiment in Run 1 proton–proton collisions at the LHC

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    This paper presents the method and performance of primary vertex reconstruction in proton–proton collision data recorded by the ATLAS experiment during Run 1 of the LHC. The studies presented focus on data taken during 2012 at a centre-of-mass energy of √s=8 TeV. The performance has been measured as a function of the number of interactions per bunch crossing over a wide range, from one to seventy. The measurement of the position and size of the luminous region and its use as a constraint to improve the primary vertex resolution are discussed. A longitudinal vertex position resolution of about 30μm is achieved for events with high multiplicity of reconstructed tracks. The transverse position resolution is better than 20μm and is dominated by the precision on the size of the luminous region. An analytical model is proposed to describe the primary vertex reconstruction efficiency as a function of the number of interactions per bunch crossing and of the longitudinal size of the luminous region. Agreement between the data and the predictions of this model is better than 3% up to seventy interactions per bunch crossing

    Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

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    A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements

    Two high-risk susceptibility loci at 6p25.3 and 14q32.13 for Waldenström macroglobulinemia

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    Waldenström macroglobulinemia (WM)/lymphoplasmacytic lymphoma (LPL) is a rare, chronic B-cell lymphoma with high heritability. We conduct a two-stage genome-wide association study of WM/LPL in 530 unrelated cases and 4362 controls of European ancestry and identify two high-risk loci associated with WM/LPL at 6p25.3 (rs116446171, near EXOC2 and IRF4; OR = 21.14, 95% CI: 14.40–31.03, P = 1.36 × 10 −54 ) and 14q32.13 (rs117410836, near TCL1; OR = 4.90, 95% CI: 3.45–6.96, P = 8.75 × 10 −19 ). Both risk alleles are observed at a low frequency among controls (~2–3%) and occur in excess in affected cases within families. In silico data suggest that rs116446171 may have functional importance, and in functional studies, we demonstrate increased reporter transcription and proliferation in cells transduced with the 6p25.3 risk allele. Although further studies are needed to fully elucidate underlying biological mechanisms, together these loci explain 4% of the familial risk and provide insights into genetic susceptibility to this malignancy. © 2018, The Author(s).Peer reviewe

    Realtime follow-up of astrophysical transients with the IceCube Neutrino Observatory

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    A multi-detector EAS reconstruction framework for IceCube

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    Three-year performance of the IceAct telescopes at the IceCube Neutrino Observatory

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    IceAct is an array of compact Imaging Air Cherenkov Telescopes at the ice surface as part of the IceCube Neutrino Observatory. The telescopes, featuring a camera of 61 silicon photomultipliers and fresnel-lens-based optics, are optimized to be operated in harsh environmental conditions, such as at the South Pole. Since 2019, the first two telescopes have been operating in a stereoscopic configuration in the center of IceCube\u27s surface detector IceTop. With an energy threshold of about 10 TeV and a wide field-of-view, the IceAct telescopes show promising capabilities of improving current cosmic-ray composition studies: measuring the Cherenkov light emissions in the atmosphere adds new information about the shower development not accessible with the current detectors. First simulations indicate that the added information of a single telescope leads, e.g., to an improved discrimination between flux contributions from different primary particle species in the sensitive energy range. We review the performance and detector operations of the telescopes during the past 3 years (2020-2022) and give an outlook on the future of IceAct

    Highlights from the IceCube Neutrino Observatory

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    As IceCube surpasses a decade of operation in the full detector configuration, results that drive forward the fields of neutrino astronomy, cosmic ray physics, multi-messenger astronomy, particle physics, and beyond continue to emerge at an accelerated pace. IceCube data is dominated by background events, and thus teasing out the signal is the common challenge to most analyses. Statistical accumulation of data, along with better understanding of the background fluxes, the detector, and continued development of our analysis tools have produced many profound results that were presented at ICRC2023. Highlights covered here include the first neutrino observation of the Galactic Plane, the first observation of a steady emission neutrino point source NGC1068, new characterizations of the cosmic ray flux and its secondary particles, and a possible new era in measuring the energy spectrum of the diffuse astrophysical flux. IceCube is poised to make more discoveries and drive fields forward in the near future with many novel analyses coming online

    Search for the rare interactions of neutrinos from distant point sources with the IceCube Neutrino Telescope

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    The recent discovery and evidence of neutrino signals from distant sources, TXS 0506+056 and NGC 1068 respectively, provide opportunities to search for rare interactions of neutrinos that they might encounter on their paths. One potential scenario of interest is the interaction between neutrinos and dark matter, which is invisible and expected to be abundantly spread over the Universe. Various astrophysical observations have implied the existence of dark matter. When high-energy neutrinos from extragalactic sources interact with dark matter during their propagation, their spectra might show suppressions at specific energy ranges, where such interactions occur. These attenuation signatures from the interaction might be measurable on Earth with large neutrino telescopes such as the IceCube Neutrino Observatory. This analysis is focused on the search for rare interactions of high-energy neutrinos from the IceCube-identified astrophysical neutrino sources with dark matter in sub-GeV masses and several benchmark mediator cases using the upgoing track-like events. In this poster, sensitivity studies about the interaction of neutrinos and dark matter are presented

    A new simulation framework for IceCube Upgrade calibration using IceCube Upgrade Camera system

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    Currently, an upgrade consisting of seven densely instrumented strings in the center of the volume of the IceCube detector with new digital optical modules (DOMs) is being built. On each string, DOMs will be regularly spaced with a vertical separation of 3 m between depths of 2160 m and 2430 m below the surface of the ice, which is a denser configuration compared to the existing DOMs of IceCube detector. For a precise calibration of the IceCube Upgrade it is important to understand the properties of the ice, both inside and surrounding the deployment holes.LEDs and Camera systems, which are developed and produced at Sungkyunkwan university, are installed in every single DOM to measure these properties. For these calibration measurements, a new simulation framework, which produces expected images from various geometric and optical variables has been developed and images produced from the simulation are expected to be used to develop an analysis framework for the IceCube Upgrade camera calibration system and for the design of the IceCube Gen2 camera system
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