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International Ocean Discovery Program Site U1534 presents an opportunity to study the evolution of subantarctic surface waters in the Atlantic Ocean and investigate Subantarctic Front dynamics during glacial–interglacial transitions. Here we document stable carbon and oxygen isotopes (δ13C and δ18O) in the planktonic foraminifera Globigerina bulloides and Neogloboquadrina pachyderma (sinistral), as well as species abundances of all planktonic foraminifera present in the splice section of Site U1534 interpreted to represent Marine Isotope Stage 11 based on the shipboard stratigraphy. The planktonic assemblage is dominated by N. pachyderma (sinistral), with minor occurrences of other calcareous species; the lowest N. pachyderma (sinistral) abundances suggest the warmest upper ocean temperatures at ~43–44 m core composite depth below seafloor, Method A (CCSF-A). Results demonstrate that δ13C in N. pachyderma (sinistral) and G. bulloides varies from −0.12‰ to 1.01‰ and from 0.19‰ to 1.11‰, respectively. δ18O in N. pachyderma (sinistral) and G. bulloides varies from 1.68‰ to 2.92‰ and from 2.14‰ to 2.97‰, respectively. δ18O values oscillate through the section but are generally lowest near 43–44 m CCSF-A. 

Abstract The climatic optimum of Marine Isotope Stage (MIS) 11, MIS 11c, was a remarkably long warmer‐than‐present climate interval with prolonged elevated atmospheric CO₂levels. While the Pacific Southern Ocean has a strong leverage on atmospheric CO₂through oceanic CO₂release, past changes in carbon cycle dynamics in this region and their influence on atmospheric CO₂during MIS 11 and the glacial inception to MIS 10 remain poorly constrained. Here, we assess changes in vertical mixing (planktic vs. benthic foraminiferal stable carbon isotope gradients) and respired carbon storage (Cibicides kullenbergiB/Ca) in the central Pacific Southern Ocean at International Ocean Discovery Program Site U1540 for MIS 11 and the onset of glacial MIS 10, complemented with previous reconstructions of deep ocean oxygenation (foraminiferal U/Mn), ocean temperature (Uvigerinaspp. Mg/Ca,Neogloboquadrina pachydermaabundances) and ocean circulation (foraminiferal/fish debris Nd isotopes). Our data reveal a temporal offset between ocean cooling/global ice sheet growth and Southern Ocean carbon storage changes after peak MIS 11c warmth. This coincides with minimum obliquity, which favors southern‐hemisphere westerly wind (SWW)‐driven upwelling of CO₂‐rich waters in the Southern Ocean and CO₂evasion (via obliquity control on meridional pressure gradients and SWW position/strength), explaining high sustained atmospheric CO₂levels during MIS 11c. The glacial inception following peak MIS 11c thus shows opposing effects of low obliquity favoring ice sheet growth through polar cooling and poleward moisture supply, yet maintaining high atmospheric CO₂levels through continued Southern Ocean CO₂outgassing that likely decelerated global ice sheet growth. 

Abstract Despite the global impact of the coronavirus disease 2019 pandemic, the question of whether mandated interventions have similar economic and public health effects as spontaneous behavioural change remains unresolved. Addressing this question, and understanding differential effects across socioeconomic groups, requires building quantitative and fine-grained mechanistic models. Here we introduce a data-driven, granular, agent-based model that simulates epidemic and economic outcomes across industries, occupations and income levels. We validate the model by reproducing key outcomes of the first wave of coronavirus disease 2019 in the New York metropolitan area. The key mechanism coupling the epidemic and economic modules is the reduction in consumption due to fear of infection. In counterfactual experiments, we show that a similar trade-off between epidemic and economic outcomes exists both when individuals change their behaviour due to fear of infection and when non-pharmaceutical interventions are imposed. Low-income workers, who perform in-person occupations in customer-facing industries, face the strongest trade-off. 

Abstract In this paper we review the physics opportunities at linear$$\mathrm{e}^{+}\mathrm{e}^{-} $$ $e^{+}{e}^{-}$colliders with a special focus on high centre-of-mass energies and beam polarisation, take a fresh look at the various accelerator technologies available or under development and, for the first time, discuss how a facility first equipped with a technology that is mature today could be upgraded with technologies of tomorrow to reach much higher energies and/or luminosities. In addition, we discuss detectors, alternative collider modes, as well as opportunities for beyond-collider experiments and R&D facilities as part of a linear collider facility (LCF). The material of this paper supports all plans for$$\mathrm{e}^{+}\mathrm{e}^{-} $$ $e^{+}{e}^{-}$linear colliders and the additional opportunities they offer, independently of technology choice or proposed site, as well as R&D for advanced accelerator technologies. This joint perspective on the physics goals, early technologies and upgrade strategies has been developed by the LCVision team based on an initial discussion at LCWS2024 in Tokyo and a follow-up at the LCVision Community Event at CERN in January 2025. It heavily builds on decades of achievements of the global linear collider community, in particular in the context of CLIC and ILC. 

Abstract Ultrahigh-energy cosmic rays are known to be mainly of extragalactic origin, and their propagation is limited by energy losses, so their arrival directions are expected to correlate with the large-scale structure of the local Universe. In this work, we investigate the possible presence of intermediate-scale excesses in the flux of the most energetic cosmic rays from the direction of the supergalactic plane region using events with energies above 20 EeV recorded with the surface detector array of the Pierre Auger Observatory up to 2022 December 31, with a total exposure of 135,000 km²sr yr. The strongest indication for an excess that we find, with a posttrial significance of 3.1σ, is in the Centaurus region, as in our previous reports, and it extends down to lower energies than previously studied. We do not find any strong hints of excesses from any other region of the supergalactic plane at the same angular scale. In particular, our results do not confirm the reports by the Telescope Array Collaboration of excesses from two regions in the Northern Hemisphere at the edge of the field of view of the Pierre Auger Observatory. With a comparable integrated exposure over these regions, our results there are in good agreement with the expectations from an isotropic distribution. 

Abstract The combined fit of the measured energy spectrum and shower maximum depth distributions of ultra-high-energy cosmic rays is known to constrain the parameters of astrophysical models with homogeneous source distributions. Studies of the distribution of the cosmic-ray arrival directions show a better agreement with models in which a fraction of the flux is non-isotropic and associated with the nearby radio galaxy Centaurus A or with catalogs such as that of starburst galaxies. Here, we present a novel combination of both analyses by a simultaneous fit of arrival directions, energy spectrum, and composition data measured at the Pierre Auger Observatory. The model takes into account a rigidity-dependent magnetic field blurring and an energy-dependent evolution of the catalog contribution shaped by interactions during propagation. We find that a model containing a flux contribution from the starburst galaxy catalog of around 20% at 40 EeV with a magnetic field blurring of around 20° for a rigidity of 10 EV provides a fair simultaneous description of all three observables. The starburst galaxy model is favored with a significance of 4.5σ (considering experimental systematic effects) compared to a reference model with only homogeneously distributed background sources. By investigating a scenario with Centaurus A as a single source in combination with the homogeneous background, we confirm that this region of the sky provides the dominant contribution to the observed anisotropy signal. Models containing a catalog of jetted active galactic nuclei whose flux scales with the γ-ray emission are, however, disfavored as they cannot adequately describe the measured arrival directions.