36 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

    The BM@N spectrometer at the NICA accelerator complex

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    BM@N (Baryonic Matter at Nuclotron) is the first experiment operating and taking data at the Nuclotron/NICA ion-accelerating complex.The aim of the BM@N experiment is to study interactions of relativistic heavy-ion beams with fixed targets. We present a technical description of the BM@N spectrometer including all its subsystems.Comment: 34 pages, 47 figures, 6 table

    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

    Simulation and analysis software for the NICA experiments

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    Software frameworks, developed for the NICA experiments are described briefly. The tools used for the physics event generation, detector simulation, particle reconstruction and visualization are considered
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