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Wolfgang Wagner

Bio: Wolfgang Wagner is an academic researcher from Vienna University of Technology. The author has contributed to research in topics: Large Hadron Collider & Top quark. The author has an hindex of 156, co-authored 2342 publications receiving 123391 citations. Previous affiliations of Wolfgang Wagner include University of Pennsylvania & University of Amsterdam.


Papers
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Georges Aad1, A. Kupco2, Peter Davison3, Samuel Webb4  +2878 moreInstitutions (211)
TL;DR: In this article, a search for pair production of vector-like quarks, both up-type and down-type (B), as well as for four-top-quark production, is presented.
Abstract: A search for pair production of vector-like quarks, both up-type (T) and down-type (B), as well as for four-top-quark production, is presented. The search is based on pp collisions at TeV recorded in 2012 with the ATLAS detector at the CERN Large Hadron Collider and corresponding to an integrated luminosity of 20.3 fb(-1). Data are analysed in the lepton-plus-jets final state, characterised by an isolated electron or muon with high transverse momentum, large missing transverse momentum and multiple jets. Dedicated analyses are performed targeting three cases: a T quark with significant branching ratio to a W boson and a b-quark , and both a T quark and a B quark with significant branching ratio to a Higgs boson and a third-generation quark ( respectively). No significant excess of events above the Standard Model expectation is observed, and 95% CL lower limits are derived on the masses of the vector-like T and B quarks under several branching ratio hypotheses assuming contributions from T -> Wb, Zt, Ht and B -> Wt, Zb, Hb decays. The 95% CL observed lower limits on the T quark mass range between 715 GeV and 950 GeV for all possible values of the branching ratios into the three decay modes, and are the most stringent constraints to date. Additionally, the most restrictive upper bounds on four-top-quark production are set in a number of new physics scenarios.

144 citations

Journal ArticleDOI
TL;DR: In this paper, the authors used state-of-the-art airborne laser scanning (ALS) technology and software packages to map canopy heights and to estimate tree heights for a 128 km2 region in the western part of the Austrian Alps.
Abstract: Airborne laser scanning (ALS) is currently one of the most promising remote sensing techniques for quantitative retrieval of forest parameters. While ALS has reached an operational status for mapping of boreal forests, its large area application over mountainous environments is lacking behind. This is because alpine forests often have high horizontal and vertical structural diversity and are situated in steep terrain. Also, ALS data acquisition and processing is more demanding over mountainous areas than over relatively flat regions. In this study we have used state-of-the-art ALS technology and software packages to map canopy heights and to estimate tree heights for a 128 km2 region in the western part of the Austrian Alps. Spruce and fir are the dominant tree species. Rather than employing data and methods tuned for a particular task and for a small study area, we solely use data and methods which already serve other operational applications. Thus, it is ensured that the results obtained in this study are of practical relevance. For the validation of the ALS derived canopy heights we have used 22 000 ground control points and field-measured forest inventory data from 103 sample plots, which are operationally used by the local forest administration. The validation of the digital terrain model (DTM) with the ground control points shows that over non-forested terrain DTM errors increase from 10 cm for relatively flat terrain (local slope

143 citations

Journal ArticleDOI
TL;DR: It is argued that Internet forums can yield an abundance of useful “natural” discursive data for social scientific research, including data-sampling strategies, the refinement of the data for computer-assisted qualitative and quantitative analysis, and strategies for in-depth analysis.
Abstract: Within Internet forums, members of certain (online) communities discuss matters of concern to the respective groups, with comparatively few social restraints. For radical, extremist, and other ideologically “sensitive” groups and organizations in particular, Internet forums are a very efficient and widely used tool to connect members, inform others about the group’s agenda, and attract new members. Whereas members of such groups may be reluctant to express their opinions in interviews or surveys, we argue that Internet forums can yield an abundance of useful “natural” discursive data for social scientific research. Based on two exemplary studies, we present a practical guide for the analysis of such data, including data-sampling strategies, the refinement of the data for computer-assisted qualitative and quantitative analysis, and strategies for in-depth analysis. The first study is an in-depth analysis of discourses within a German neo-Nazi discussion board. In the second, nine online forums for young Ge...

143 citations

Journal ArticleDOI
Georges Aad1, T. Abajyan2, Brad Abbott3, J. Abdallah4  +2919 moreInstitutions (195)
TL;DR: A combined search for the Standard Model Higgs boson with the ATLAS detector at the LHC is presented in this article, where the data sets used correspond to integrated luminosities from 4.6 fb (-1) to 4.9 fb(-1) of proton-proton collisions collected at root s = 7 TeV in 2011.
Abstract: A combined search for the Standard Model Higgs boson with the ATLAS detector at the LHC is presented. The data sets used correspond to integrated luminosities from 4.6 fb(-1) to 4.9 fb(-1) of proton-proton collisions collected at root s = 7 TeV in 2011. The Higgs boson mass ranges of 111.4 GeV to 116.6 GeV, 119.4 GeV to 122.1 GeV, and 129.2 GeV to 541 GeV are excluded at the 95% confidence level, while the range 120 GeV to 560 GeV is expected to be excluded in the absence of a signal. An excess of events is observed at Higgs boson mass hypotheses around 126 GeV with a local significance of 2.9 standard deviations (sigma). The global probability for the background to produce an excess at least as significant anywhere in the entire explored Higgs boson mass range of 110-600 GeV is estimated to be similar to 15%, corresponding to a significance of approximately 1 sigma.

143 citations

Journal ArticleDOI
A. Abulencia1, Jahred Adelman2, T. Affolder3, T. Akimoto4  +615 moreInstitutions (55)
TL;DR: In this paper, the authors measured the polarizations of J/psi and {psi}(2S) mesons as functions of their transverse momentum p{sub T} when they are produced promptly in the rapidity range |y| < 0.6 with p{ sub T} {ge} 5 GeV/c.
Abstract: The authors have measured the polarizations of J/{psi} and {psi}(2S) mesons as functions of their transverse momentum p{sub T} when they are produced promptly in the rapidity range |y| < 0.6 with p{sub T} {ge} 5 GeV/c. The analysis is performed using a data sample with an integrated luminosity of about 800 pb{sup -1} collected by the CDF II detector. For both vector mesons, they find that the polarizations become increasingly longitudinal as p{sub T} increases from 5 to 30 GeV/c. These results are compared to the predictions of non-relativistic quantum chromo-dynamics and other contemporary models. The polarizations of J/{psi} and {psi}(2S) mesons from B-hadron decays are also reported.

143 citations


Cited by
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[...]

08 Dec 2001-BMJ
TL;DR: There is, I think, something ethereal about i —the square root of minus one, which seems an odd beast at that time—an intruder hovering on the edge of reality.
Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

33,785 citations

01 May 1993
TL;DR: Comparing the results to the fastest reported vectorized Cray Y-MP and C90 algorithm shows that the current generation of parallel machines is competitive with conventional vector supercomputers even for small problems.
Abstract: Three parallel algorithms for classical molecular dynamics are presented. The first assigns each processor a fixed subset of atoms; the second assigns each a fixed subset of inter-atomic forces to compute; the third assigns each a fixed spatial region. The algorithms are suitable for molecular dynamics models which can be difficult to parallelize efficiently—those with short-range forces where the neighbors of each atom change rapidly. They can be implemented on any distributed-memory parallel machine which allows for message-passing of data between independently executing processors. The algorithms are tested on a standard Lennard-Jones benchmark problem for system sizes ranging from 500 to 100,000,000 atoms on several parallel supercomputers--the nCUBE 2, Intel iPSC/860 and Paragon, and Cray T3D. Comparing the results to the fastest reported vectorized Cray Y-MP and C90 algorithm shows that the current generation of parallel machines is competitive with conventional vector supercomputers even for small problems. For large problems, the spatial algorithm achieves parallel efficiencies of 90% and a 1840-node Intel Paragon performs up to 165 faster than a single Cray C9O processor. Trade-offs between the three algorithms and guidelines for adapting them to more complex molecular dynamics simulations are also discussed.

29,323 citations

28 Jul 2005
TL;DR: PfPMP1)与感染红细胞、树突状组胞以及胎盘的单个或多个受体作用,在黏附及免疫逃避中起关键的作�ly.
Abstract: 抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1(PfPMP1)与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用,在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员,通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

18,940 citations

Journal ArticleDOI
TL;DR: In this paper, Imagined communities: Reflections on the origin and spread of nationalism are discussed. And the history of European ideas: Vol. 21, No. 5, pp. 721-722.

13,842 citations

Journal ArticleDOI
TL;DR: Reading a book as this basics of qualitative research grounded theory procedures and techniques and other references can enrich your life quality.

13,415 citations