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Workshop report on new directions in soft x-ray photoabsorption
The Workshop Report integrates what was said at the Workshop on New Directions in Soft X-Ray Photoabsorption, which focused on the region from 100 eV to 10 keV. The report clarifies the current state of theory and experiment and identifies the opportunities which new theoretical methods and experimental facilities could be expected to provide. The understanding of photoabsorption (which requires experimental photoabsorption cross section data) is a key to understanding the properties and behavior of atoms, molecules and solids. The Workshop participants were forty-three physicists and quantum chemists, from twenty-four institutions in four countries, all interested in photoabsorption from different perspectives
Production of {\pi}+ and K+ mesons in argon-nucleus interactions at 3.2 AGeV
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
Population genomics of post-glacial western Eurasia.
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
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
Palaeoenvironmental implications of Palaeomicrocodium in Upper Devonian microbial mounds of the Chernyshev Swell, Timan-northern Ural Region
Widespread horse-based mobility arose around 2,200 BCE in Eurasia
This is the author accepted manuscript. The final version is available from Nature Research via the DOI in this recordData availability:All collapsed and paired-end sequence data for samples sequenced in this study are available in compressed
FASTQ format through the European Nucleotide Archive under accession number PRJEB71445, together
with rescaled and trimmed bam sequence alignments against the nuclear horse reference genomes.
Previously published ancient data used in this study are available under accession numbers PRJEB7537,
PRJEB10098, PRJEB10854, PRJEB22390, PRJEB31613, and PRJEB44430, and detailed in Supplementary
Table 1. The genomes of 78 modern horses, publicly available, were also accessed as indicated in their
corresponding original publications, and in Supplementary Table 1.Code availability: The software to calculate generation time changes based on the recombination clock is available without
restriction on Bitbucket (https://bitbucket.org/plibradosanz/generationtime/src/master/) and Zenodo
(10.5281/zenodo.10842666; https://zenodo.org/records/10842666)Horses revolutionized human history with fast mobility. However, the timeline between their domestication and widespread integration as a means of transportation remains contentious. Here we assemble a large collection of 475 ancient horse genomes to assess the period when these animals were first reshaped by human agency in Eurasia. We find that reproductive control of the modern domestic lineage emerged ~2,200 BCE (Before Common Era), through close kin mating and shortened generation times. Reproductive control emerged following a severe domestication bottleneck starting no earlier than ~2,700 BCE, and coincided with a sudden expansion across Eurasia that ultimately resulted in the replacement of nearly every local horse lineage. This expansion marked the rise of widespread horse-based mobility in human history, which refutes the commonly-held narrative of large horse herds accompanying the massive migration of steppe peoples across Europe ~3,000 BCE and earlier. Finally, we detect significantly shortened generation times at Botai ~3,500 BCE, a settlement from Central Asia associated with corrals and a subsistence economy centered on horses. This supports local horse husbandry before the rise of modern domestic bloodlines.Arts and Humanities Research Council (AHRC
Unperturbed inverse kinematics nucleon knockout measurements with a carbon beam
From superconductors to atomic nuclei, strongly-interacting many-body systems
are ubiquitous in nature. Measuring the microscopic structure of such systems
is a formidable challenge, often met by particle knockout scattering
experiments. While such measurements are fundamental for mapping the structure
of atomic nuclei, their interpretation is often challenged by quantum
mechanical initial- and final-state interactions (ISI/FSI) of the incoming and
scattered particles. Here we overcome this fundamental limitation by measuring
the quasi-free scattering of 48 GeV/c 12C ions from hydrogen. The distribution
of single protons is studied by detecting two protons at large angles in
coincidence with an intact 11B nucleus. The 11B detection is shown to select
the transparent part of the reaction and exclude the otherwise large ISI/FSI
that would break the 11B apart. By further detecting residual 10B and 10Be
nuclei, we also identified short-range correlated (SRC) nucleon-nucleon pairs,
and provide direct experimental evidence for the separation of the pair
wave-function from that of the residual many-body nuclear system. All measured
reactions are well described by theoretical calculations that do not contain
ISI/FSI distortions. Our results thus showcase a new ability to study the
short-distance structure of short-lived radioactive atomic nuclei at the
forthcoming FAIR and FRIB facilities. These studies will be pivotal for
developing a ground-breaking microscopic understanding of the structure and
properties of nuclei far from stability and the formation of visible matter in
the universe.Comment: Accepted for publication in Nature Physics. 28 pages, 19 figures, and
1 table including main text, Methods, and Supplementary material