1,064 research outputs found

    The LEP project-status report

    Get PDF

    The Site Groß Fredenwalde, NE-Germany, and the Early Cemeteries of Northern Europe

    Get PDF
    The Mesolithic burial site Groß Fredenwalde, NE-Germany, discovered in 1962, had remained a poorly understood part of the Mesolithic burial record for decades. Since 2012, the site has been under re-investigation. New discoveries confirm the presence of several single and multiple inhumation graves. Groß Fredenwalde stands out as the largest and one of the oldest Mesolithic cemeteries in North-central Europe. Its use period can be separated into two phases: a main phase in the late seventh millennium cal BC to the early sixth millennium cal BC and a later single burial c. 4900 cal BC. Here the state of research on the site is presented and selected characteristics are discussed in the context of early cemeteries of Northern and North-eastern Europe

    Research in Monumental Constructions in Antiquity

    Get PDF
    Ancient civilizations have passed down to us a vast range of monumental structures. Monumentality is a complex phenomenon that we address here as ‘XXL’. It encompasses a large range of different aspects, such as sophisticated technical and logistical skills and the vast economic resources required. This contribution takes a closer look at the special interdependence of space and knowledge represented by such XXL projects. We develop a set of objective criteria for determining whether an object qualifies as ‘XXL’, in order to permit a broadly framed study comparing manifestations of the XXL phenomenon in different cultures and describing the functional and conceptional role of the phenomenon in antiquity. Finally, we illustrate how these criteria are being applied in the study of large construction projects in ancient civilizations through six case studies

    Study of Spin and Decay-Plane Correlations of W Bosons in the e+e- -> W+W- Process at LEP

    Get PDF
    Data collected at LEP at centre-of-mass energies \sqrt(s) = 189 - 209 GeV are used to study correlations of the spin of W bosons using e+e- -> W+W- -> lnqq~ events. Spin correlations are favoured by data, and found to agree with the Standard Model predictions. In addition, correlations between the W-boson decay planes are studied in e+e- -> W+W- -> lnqq~ and e+e- -> W+W- -> qq~qq~ events. Decay-plane correlations, consistent with zero and with the Standard Model predictions, are measured

    Ultrarelativistic sources in nonlinear electrodynamics

    Get PDF
    The fields of rapidly moving sources are studied within nonlinear electrodynamics by boosting the fields of sources at rest. As a consequence of the ultrarelativistic limit the delta-like electromagnetic shock waves are found. The character of the field within the shock depends on the theory of nonlinear electrodynamics considered. In particular, we obtain the field of an ultrarelativistic charge in the Born-Infeld theory.Comment: 10 pages, 3 figure

    Measurement of the Cross Section for Open-Beauty Production in Photon-Photon Collisions at LEP

    Get PDF
    The cross section for open-beauty production in photon-photon collisions is measured using the whole high-energy and high-luminosity data sample collected by the L3 detector at LEP. This corresponds to 627/pb of integrated luminosity for electron-positron centre-of-mass energies from 189GeV to 209GeV. Events containing b quarks are identified through their semi-leptonic decay into electrons or muons. The e+e- -> e+e-b b~X cross section is measured within our fiducial volume and then extrapolated to the full phase space. These results are found to be in significant excess with respect to Monte Carlo predictions and next-to-leading order QCD calculations

    Palaeogenomics of Upper Palaeolithic to Neolithic European hunter-gatherers

    Get PDF
    : Modern humans have populated Europe for more than 45,000 years1,2. Our knowledge of the genetic relatedness and structure of ancient hunter-gatherers is however limited, owing to the scarceness and poor molecular preservation of human remains from that period3. Here we analyse 356 ancient hunter-gatherer genomes, including new genomic data for 116 individuals from 14 countries in western and central Eurasia, spanning between 35,000 and 5,000 years ago. We identify a genetic ancestry profile in individuals associated with Upper Palaeolithic Gravettian assemblages from western Europe that is distinct from contemporaneous groups related to this archaeological culture in central and southern Europe4, but resembles that of preceding individuals associated with the Aurignacian culture. This ancestry profile survived during the Last Glacial Maximum (25,000 to 19,000 years ago) in human populations from southwestern Europe associated with the Solutrean culture, and with the following Magdalenian culture that re-expanded northeastward after the Last Glacial Maximum. Conversely, we reveal a genetic turnover in southern Europe suggesting a local replacement of human groups around the time of the Last Glacial Maximum, accompanied by a north-to-south dispersal of populations associated with the Epigravettian culture. From at least 14,000 years ago, an ancestry related to this culture spread from the south across the rest of Europe, largely replacing the Magdalenian-associated gene pool. After a period of limited admixture that spanned the beginning of the Mesolithic, we find genetic interactions between western and eastern European hunter-gatherers, who were also characterized by marked differences in phenotypically relevant variants
    corecore