This study presents the analysis of carbon isotope discrimination (Δ) in cereal and faba bean seeds from archaeological sites as a rapid method of evaluating the occurrence or otherwise of ancient ...irrigation in the Mediterranean basin. Further, application to the south-eastern Iberian Peninsula, one of the regions of the western Mediterranean basin in which advanced social structures first appeared, is reported. Currently there is a strong debate about when irrigation practices started in this region. It has been argued, on the basis of scattered, indirect evidence, that irrigation was already practiced during the Bronze Age (from 4400bp). However, this remains to be confirmed. Kernels of durum wheat, hulled and naked barley and faba bean grains from a set of archaeological sites in the south-eastern Iberian Peninsula were analysed. Samples ranged from late Neolithic (about 6500bp) to the Iron Age (2400bp). None of the results, apart from those of the faba bean, support the existence of irrigation practices during this period. Grains of faba bean showed consistently high values of Δ at all the archaeological sites studied. This could reflect not only growth habit, faba beans being less determined plants than cereals, but also selective irrigation of faba bean crops.
Carbon isotope discrimination (Δ) was determined for kernels of six‐row barley and durum wheat cultivated in the western Mediterranean basin during the last seven millennia. Samples came from ...different archaeological sites in Catalonia (north‐east Spain) and in the south‐east of Spain (mainly eastern Andalusia). Samples from the present were also analysed. Mean values of Δ for barley and durum wheat grains decreased slightly from Neolithic (7000–5000 BP) to Chalcolithic‐Bronze (5000–3000 BP) and Iron ages (3000–2200 BP) both in Catalonia and in south‐east (SE) Spain. Values were consistently lower in SE Spain than in Catalonia throughout these five millennia, which suggests that Catalonia was less arid than SE Spain in this period. Within a given region, current discrimination values for kernels of the same cereal species cultivated under rainfed conditions were lower than those of archaeological grains, which implies more arid conditions at present. Furthermore, an empirical relationship between Δ of mature kernels and total precipitation (plus irrigation where applicable) during grain filling (r2 = 0.73, N = 25) was established for barley, currently cultivated at different locations in the western Mediterranean basin in Spain. The resulting relationship was applied to the Δ data for barley kernels from 10 archaeological sites in Catalonia and 10 sites in SE Spain, to estimate the precipitation during grain filling at the time the kernels were produced. For both regions, current climatic conditions are consistently more arid than those inferred for the Neolithic, Bronze and Iron ages. In addition, although Catalonia was estimated to have had consistently wetter conditions (about 20% more precipitation) than SE Spain throughout these millennia, differences in precipitation between these two regions have recently increased, with 79% more precipitation in Catalonia. Results indicate a more rapid increase in aridity in SE Spain than in Catalonia, probably produced during the last few centuries, and due to anthropogenic causes.
New Physics Searches at Kaon and Hyperon Factories Goudzovski, Evgueni; Redigolo, Diego; Tobioka, Kohsaku ...
CERN Document Server (European Organization for Nuclear Research),
05/2023
Paper, Journal Article
Odprti dostop
Rare meson decays are among the most sensitive probes of both heavy and light new physics. Among them, new physics searches using kaons benefit from their small total decay widths and the ...availability of very large datasets. On the other hand, useful complementary information is provided by hyperon decay measurements. We summarize the relevant phenomenological models and the status of the searches in a comprehensive list of kaon and hyperon decay channels. We identify new search strategies for under-explored signatures, and demonstrate that the improved sensitivities from current and next-generation experiments could lead to a qualitative leap in the exploration of light dark sectors.
PDF
