1. |
- Abdallah, J., et al.
(author)
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Mechanical construction and installation of the ATLAS tile calorimeter
- 2013
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In: Journal of Instrumentation. - 1748-0221. ; 8, s. T11001-
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Journal article (peer-reviewed)abstract
- This paper summarises the mechanical construction and installation of the Tile Calorimeter for the ATLAS experiment at the Large Hadron Collider in CERN, Switzerland. The Tile Calorimeter is a sampling calorimeter using scintillator as the sensitive detector and steel as the absorber and covers the central region of the ATLAS experiment up to pseudorapidities +/- 1.7. The mechanical construction of the Tile Calorimeter occurred over a period of about 10 years beginning in 1995 with the completion of the Technical Design Report and ending in 2006 with the installation of the final module in the ATLAS cavern. During this period approximately 2600 metric tons of steel were transformed into a laminated structure to form the absorber of the sampling calorimeter. Following instrumentation and testing, which is described elsewhere, the modules were installed in the ATLAS cavern with a remarkable accuracy for a structure of this size and weight.
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2. |
- Abdallah, J., et al.
(author)
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The optical instrumentation of the ATLAS Tile Calorimeter
- 2013
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In: Journal of Instrumentation. - 1748-0221. ; 8, s. P01005-
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Journal article (peer-reviewed)abstract
- The Tile Calorimeter, covering the central region of the ATLAS experiment up to pseudorapidities of +/-1.7, is a sampling device built with scintillating tiles that alternate with iron plates. The light is collected in wave-length shifting (WLS) fibers and is read out with photomultipliers. In the characteristic geometry of this calorimeter the tiles lie in planes perpendicular to the beams, resulting in a very simple and modular mechanical and optical layout. This paper focuses on the procedures applied in the optical instrumentation of the calorimeter, which involved the assembly of about 460,000 scintillator tiles and 550,000 WLS fibers. The outcome is a hadronic calorimeter that meets the ATLAS performance requirements, as shown in this paper.
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3. |
- Jakobsson, Martin, et al.
(author)
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Evidence for an ice shelf covering the central Arctic Ocean during the penultimate glaciation
- 2016
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In: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 7
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Journal article (peer-reviewed)abstract
- The hypothesis of a km-thick ice shelf covering the entire Arctic Ocean during peak glacial conditions was proposed nearly half a century ago. Floating ice shelves preserve few direct traces after their disappearance, making reconstructions difficult. Seafloor imprints of ice shelves should, however, exist where ice grounded along their flow paths. Here we present new evidence of ice-shelf groundings on bathymetric highs in the central Arctic Ocean, resurrecting the concept of an ice shelf extending over the entire central Arctic Ocean during at least one previous ice age. New and previously mapped glacial landforms together reveal flow of a spatially coherent, in some regions41-km thick, central Arctic Ocean ice shelf dated to marine isotope stage 6 (similar to 140 ka). Bathymetric highs were likely critical in the ice-shelf development by acting as pinning points where stabilizing ice rises formed, thereby providing sufficient back stress to allow ice shelf thickening.
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4. |
- Lobkovsky, L. I., et al.
(author)
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Recent geological-geomorphological processes on the east Arctic shelf : Results of the expedition of the icebreaker Oden in 2014
- 2015
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In: Oceanology. - 0001-4370 .- 1531-8508. ; 55:6, s. 926-929
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Journal article (peer-reviewed)abstract
- Results obtained by the International Arctic marine expedition (SWERUS-C3) in June to October of 2014, using advanced seismoacoustic equipment, confirmed the wide distribution of potentially hazardous exogenic geological-geomorphological natural processes on the eastern Arctic shelf of Russia. In Arctic seas, serious hazards are represented by ice exaration and its consequences must be taken into consideration when developing oil and gas fields on the shelf. Many areas with anomalous gas saturation of sediments and gas seeps established in the region under consideration may represent global hazard: further increases in methane emissions may represent global risks. The minimization of these and other geological risks in constructing different technogenic objects on the shelf should be a first-priority task in the economic development of the Arctic region.
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