2,511 research outputs found

    PEN as self-vetoing structural Material

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    Polyethylene Naphtalate (PEN) is a mechanically very favorable polymer. Earlier it was found that thin foils made from PEN can have very high radio-purity compared to other commercially available foils. In fact, PEN is already in use for low background signal transmission applications (cables). Recently it has been realized that PEN also has favorable scintillating properties. In combination, this makes PEN a very promising candidate as a self-vetoing structural material in low background experiments. Components instrumented with light detectors could be built from PEN. This includes detector holders, detector containments, signal transmission links, etc. The current R\&D towards qualification of PEN as a self-vetoing low background structural material is be presented.Comment: 4 pages, 7 figures, contribution to Proceedings of the sixth workshop on Low Radioactivity Techniques 2017, 23-27 May 2017 Seoul, to be published at AIP, editor: D. Leonar

    BASIS WEIGHT UNIFORMITY OF LIGHTLY NEEDLED HYDROENTANGLED COTTON AND COTTON BLEND WEBS

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    New nonwoven products containing cotton and Lyocell (Trademarked name Tencel), low temperature thermal-bondable bicomponent olefin/polyester, or comber noils were developed using needlepunching and spunlacing (hydroentanglement). Webs containing five different blends were prepared by either light needlepunching, or light needlepunching followed by hydroentangling. We acquired detailed basis weight uniformity measurements to learn about processing and the influence of fiber blend composition on web uniformity. Basis weight uniformity was evaluated without regard to web direction ("Total" uniformity), along the machine direction (MD uniformity) and across the cross direction (CD uniformity) at numerous size resolutions. We observed that blending manufactured fibers (either Tencel or olefin/polyester) with bleached cotton and comber noils substantially improved basis weight uniformity of both types of nonwovens. We also observed that subjecting needled webs to hydroentangling significantly improved Total and MD uniformities

    HV/HR-CMOS sensors for the ATLAS upgrade—concepts and test chip results

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    In order to extend its discovery potential, the Large Hadron Collider (LHC) will have a major upgrade (Phase II Upgrade) scheduled for 2022. The LHC after the upgrade, called High-Luminosity LHC (HL-LHC), will operate at a nominal leveled instantaneous luminosity of 5× 1034 cm−2 s−1, more than twice the expected Phase I . The new Inner Tracker needs to cope with this extremely high luminosity. Therefore it requires higher granularity, reduced material budget and increased radiation hardness of all components. A new pixel detector based on High Voltage CMOS (HVCMOS) technology targeting the upgraded ATLAS pixel detector is under study. The main advantages of the HVCMOS technology are its potential for low material budget, use of possible cheaper interconnection technologies, reduced pixel size and lower cost with respect to traditional hybrid pixel detector. Several first prototypes were produced and characterized within ATLAS upgrade R&D effort, to explore the performance and radiation hardness of this technology. In this paper, an overview of the HVCMOS sensor concepts is given. Laboratory tests and irradiation tests of two technologies, HVCMOS AMS and HVCMOS GF, are also given

    Radiation-hard active pixel sensors for HL-LHC detector upgrades based on HV-CMOS technology

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    Luminosity upgrades are discussed for the LHC (HL-LHC) which would make updates to the detectors necessary, requiring in particular new, even more radiation-hard and granular, sensors for the inner detector region. A proposal for the next generation of inner detectors is based on HV-CMOS: a new family of silicon sensors based on commercial high-voltage CMOS technology, which enables the fabrication of part of the pixel electronics inside the silicon substrate itself. The main advantages of this technology with respect to the standard silicon sensor technology are: low material budget, fast charge collection time, high radiation tolerance, low cost and operation at room temperature. A traditional readout chip is still needed to receive and organize the data from the active sensor and to handle high-level functionality such as trigger management. HV-CMOS has been designed to be compatible with both pixel and strip readout. In this paper an overview of HV2FEI4, a HV-CMOS prototype in 180 nm AMS technology, will be given. Preliminary results after neutron and X-ray irradiation are shown

    Аналіз деформування матеріалу з множинними тріщинами термомеханічної втоми як розломно-блокового середовища

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    Recent advances in cancer biology have emerged important roles for microRNAs (miRNAs) in regulating tumor responses. However, their function in mediating intercellular communication within the tumor microenvironment is thus far poorly explored. Here, we found miR-206 to be abrogated in human pancreatic ductal adenocarcinoma (PDAC) specimens and cell lines. We show that miR-206 directly targets the oncogenes KRAS and annexin a2 (ANXA2), thereby acting as tumor suppressor in PDAC cells by blocking cell cycle progression, cell proliferation, migration and invasion. Importantly, we identified miR-206 as a negative regulator of oncogenic KRAS-induced nuclear factor-kappa B transcriptional activity, resulting in a concomitant reduction of the expression and secretion of pro-angiogenic and pro-inflammatory factors including the cytokine interleukin-8, the chemokines (C-X-C motif) ligand 1 and (C-C motif) ligand 2, and the granulocyte macrophage colony-stimulating factor. We further show that miR-206 abrogates the expression and secretion of the potent pro-lymphangiogenic factor vascular endothelial growth factor C in pancreatic cancer cells through an NF-kappa B-independent mechanism. By using in vitro and in vivo approaches, we reveal that re-expression of miR-206 in PDAC cells is sufficient to inhibit tumor blood and lymphatic vessel formation, thus leading to a significant delay of tumor growth and progression. Taken together, our study sheds light onto the role of miR-206 as a pleiotropic modulator of different hallmarks of cancer, and as such raising the intriguing possibility that miR-206 may be an attractive candidate for miRNA-based anticancer therapies.Funding Agencies|German Federal Ministry of Education and Research (NGFN grant) [01GS0816]; Deutsche Forschungsgemeinschaft (DIP project) [WI3499/1-1]</p

    Prototype ATLAS IBL Modules using the FE-I4A Front-End Readout Chip

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    The ATLAS Collaboration will upgrade its semiconductor pixel tracking detector with a new Insertable B-layer (IBL) between the existing pixel detector and the vacuum pipe of the Large Hadron Collider. The extreme operating conditions at this location have necessitated the development of new radiation hard pixel sensor technologies and a new front-end readout chip, called the FE-I4. Planar pixel sensors and 3D pixel sensors have been investigated to equip this new pixel layer, and prototype modules using the FE-I4A have been fabricated and characterized using 120 GeV pions at the CERN SPS and 4 GeV positrons at DESY, before and after module irradiation. Beam test results are presented, including charge collection efficiency, tracking efficiency and charge sharing.Comment: 45 pages, 30 figures, submitted to JINS

    First Results of ATLASPix 3.1 Testbeam

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    The ATLASPix sensor has been developed as a monolithic High Voltage CMOS sensor candidate for the ATLAS inner tracker upgrade. The ATLASPix3 is the third version, and is the first full reticle-sized sensor developed for multi-module compatibility. The detector is operational, and has been tested as a single chip, and as a 4-layer telescopes in an electron testbeam, with energies up to 6 GeV at DESY. First results of the testbeam data analysis are presented here

    Search for direct stau production in events with two hadronic tau-leptons in root s=13 TeV pp collisions with the ATLAS detector

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    A search for the direct production of the supersymmetric partners ofτ-leptons (staus) in final stateswith two hadronically decayingτ-leptons is presented. The analysis uses a dataset of pp collisions corresponding to an integrated luminosity of139fb−1, recorded with the ATLAS detector at the LargeHadron Collider at a center-of-mass energy of 13 TeV. No significant deviation from the expected StandardModel background is observed. Limits are derived in scenarios of direct production of stau pairs with eachstau decaying into the stable lightest neutralino and oneτ-lepton in simplified models where the two staumass eigenstates are degenerate. Stau masses from 120 GeV to 390 GeV are excluded at 95% confidencelevel for a massless lightest neutralino
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