19 research outputs found

    Population genomics of post-glacial western Eurasia.

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    Western Eurasia witnessed several large-scale human migrations during the Holocene <sup>1-5</sup> . Here, to investigate the cross-continental effects of these migrations, we shotgun-sequenced 317 genomes-mainly from the Mesolithic and Neolithic periods-from across northern and western Eurasia. These were imputed alongside published data to obtain diploid genotypes from more than 1,600 ancient humans. Our analyses revealed a 'great divide' genomic boundary extending from the Black Sea to the Baltic. Mesolithic hunter-gatherers were highly genetically differentiated east and west of this zone, and the effect of the neolithization was equally disparate. Large-scale ancestry shifts occurred in the west as farming was introduced, including near-total replacement of hunter-gatherers in many areas, whereas no substantial ancestry shifts happened east of the zone during the same period. Similarly, relatedness decreased in the west from the Neolithic transition onwards, whereas, east of the Urals, relatedness remained high until around 4,000 BP, consistent with the persistence of localized groups of hunter-gatherers. The boundary dissolved when Yamnaya-related ancestry spread across western Eurasia around 5,000 BP, resulting in a second major turnover that reached most parts of Europe within a 1,000-year span. The genetic origin and fate of the Yamnaya have remained elusive, but we show that hunter-gatherers from the Middle Don region contributed ancestry to them. Yamnaya groups later admixed with individuals associated with the Globular Amphora culture before expanding into Europe. Similar turnovers occurred in western Siberia, where we report new genomic data from a 'Neolithic steppe' cline spanning the Siberian forest steppe to Lake Baikal. These prehistoric migrations had profound and lasting effects on the genetic diversity of Eurasian populations

    Publisher Correction: Population genomics of post-glacial western Eurasia.

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    Production of {\pi}+ and K+ mesons in argon-nucleus interactions at 3.2 AGeV

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    First physics results of the BM@N experiment at the Nuclotron/NICA complex are presented on {\pi}+ and K+ meson production in interactions of an argon beam with fixed targets of C, Al, Cu, Sn and Pb at 3.2 AGeV. Transverse momentum distributions, rapidity spectra and multiplicities of {\pi}+ and K+ mesons are measured. The results are compared with predictions of theoretical models and with other measurements at lower energies.Comment: 29 pages, 20 figure

    Event reconstruction in the BM@N experiment

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    In the paper, the main accent is put on development of software to be used in the BM@N experiment. The experiment is considered as a first step towards a realization of fixed target program at the NICA complex. A brief description of software used for reconstruction of track parameters in the inner tracker of the experiment is presented. The alignment procedure in automatic mode was made using the Millepede package fully integrated in the software. The obtained results illustrate a quality assurance of alignment performed using existing experimental data from experimental runs and recent results, including methodological ones from a tracking procedure, which were used for event reconstruction in the inner tracker. The importance of a precise geometry description and a realistic detector response via micro-simulations done for the GEM part of the inner tracker used for processing experimental data is emphasized. Our recent progress in this activity is discussed

    Event reconstruction in the BM@N experiment

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    In the paper, the main accent is put on development of software to be used in the BM@N experiment. The experiment is considered as a first step towards a realization of fixed target program at the NICA complex. A brief description of software used for reconstruction of track parameters in the inner tracker of the experiment is presented. The alignment procedure in automatic mode was made using the Millepede package fully integrated in the software. The obtained results illustrate a quality assurance of alignment performed using existing experimental data from experimental runs and recent results, including methodological ones from a tracking procedure, which were used for event reconstruction in the inner tracker. The importance of a precise geometry description and a realistic detector response via micro-simulations done for the GEM part of the inner tracker used for processing experimental data is emphasized. Our recent progress in this activity is discussed

    Event simulation based on three-fluid hydrodynamics for collisions at energies available at the Dubna Nuclotron-based Ion Collider Facility and at the Facility for Antiproton and Ion Research in Darmstadt

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    We present a new event generator based on the three-fluid hydrodynamics approach for the early stage of the collision, followed by a particlization at the hydrodynamic decoupling surface to join to a microscopic transport model, UrQMD, to account for hadronic final state interactions. We present first results for nuclear collisions of the FAIR/NICA energy scan program (Au+Au collisions, sNN=411\sqrt{s_{NN}}=4-11 GeV). We address the directed flow of protons and pions as well as the proton rapidity distribution for two model EoS, one with a first order phase transition the other with a crossover type softening at high densities. The new simulation program has the unique feature that it can describe a hadron-to-quark matter transition which proceeds in the baryon stopping regime that is not accessible to previous simulation programs designed for higher energies.Comment: 18 pages, 16 figures, version accepted for publication in Phys. Rev. C, before proof correction

    Three-fluid Hydrodynamics-based Event Simulator Extended by UrQMD final State interactions (THESEUS) for FAIR-NICA-SPSBES/RHIC energies

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    We present a new event generator based on the three-fluid hydrodynamics (3FH) approach, followed by a particlization at the hydrodynamic decoupling surface and a subsequent UrQMD afterburner stage based on the microscopic UrQMD transport model that accounts for hadronic final state interactions. First results for Au+Au collisions are presented. The following topics are addressed: the directed flow, transversemass spectra, as well as rapidity distributions of protons, pions and kaons for two model equations of state, one with a first-order phase transition, the other with a crossover transition. Preliminary results on the femtoscopy are also discussed.We analyze the accuracy of reproduction of the 3FH results by the new event generator and the effect of the subsequent UrQMD afterburner stage

    Three-fluid Hydrodynamics-based Event Simulator Extended by UrQMD final State interactions (THESEUS) for FAIR-NICA-SPSBES/RHIC energies

    No full text
    We present a new event generator based on the three-fluid hydrodynamics (3FH) approach, followed by a particlization at the hydrodynamic decoupling surface and a subsequent UrQMD afterburner stage based on the microscopic UrQMD transport model that accounts for hadronic final state interactions. First results for Au+Au collisions are presented. The following topics are addressed: the directed flow, transversemass spectra, as well as rapidity distributions of protons, pions and kaons for two model equations of state, one with a first-order phase transition, the other with a crossover transition. Preliminary results on the femtoscopy are also discussed.We analyze the accuracy of reproduction of the 3FH results by the new event generator and the effect of the subsequent UrQMD afterburner stage
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