Dataset used to obtain an age model of marine sediment core KH19-6 Leg 4 PC10/MC14 from the Agulhas Ridge in the South Atlantic Ocean

An age model of marine sediment core is a prerequisite to start environmental studies of the past such as paleoceanography, paleoclimatology, and paleo-hazard studies. Here we report the comprehensive geochemical dataset used to determine the age model of marine sediment cores collected from Agulhas Ridge in the South Atlantic Ocean using piston coring and multiple-coring systems during the 30th Anniversary expeditions of R/V Hakuho Maru in 2019–2020 (KH19-6 Leg.4 PC10/MC14, water depth of 4,604 m). A whole 0.29-m-long multiple core (MC14) and the top 3.27 meter of 12.28-meter-long piston core (PC10) were dated. The dataset includes radiocarbon ages of planktonic foraminifera shells and oxygen isotopes of both planktonic (Globigerinoides bulloides, Globorotalia inflata) and benthic (Gyroidina soldanii) foraminifera shells. The results suggested that the top 7.5 kyr record was lost, the ages of 3.27 m depth below sea floor was ~140 kyr ago, and sedimentation rates were 0.9–5.5 kyr/cm

Mineral Detection of Neutrinos and Dark Matter. A Whitepaper

Minerals are solid state nuclear track detectors - nuclear recoils in a mineral leave latent damage to the crystal structure. Depending on the mineral and its temperature, the damage features are retained in the material from minutes (in low-melting point materials such as salts at a few hundred degrees C) to timescales much larger than the 4.5 Gyr-age of the Solar System (in refractory materials at room temperature). The damage features from the $O(50)$ MeV fission fragments left by spontaneous fission of $^{238}$U and other heavy unstable isotopes have long been used for fission track dating of geological samples. Laboratory studies have demonstrated the readout of defects caused by nuclear recoils with energies as small as $O(1)$ keV. This whitepaper discusses a wide range of possible applications of minerals as detectors for $E_R \gtrsim O(1)$ keV nuclear recoils: Using natural minerals, one could use the damage features accumulated over $O(10)$ Myr$-O(1)$ Gyr to measure astrophysical neutrino fluxes (from the Sun, supernovae, or cosmic rays interacting with the atmosphere) as well as search for Dark Matter. Using signals accumulated over months to few-years timescales in laboratory-manufactured minerals, one could measure reactor neutrinos or use them as Dark Matter detectors, potentially with directional sensitivity. Research groups in Europe, Asia, and America have started developing microscopy techniques to read out the $O(1) - O(100)$ nm damage features in crystals left by $O(0.1) - O(100)$ keV nuclear recoils. We report on the status and plans of these programs. The research program towards the realization of such detectors is highly interdisciplinary, combining geoscience, material science, applied and fundamental physics with techniques from quantum information and Artificial Intelligence.Comment: 115 pages, many pictures of tracks. Please see the source file for higher resolution versions of some plots. v2: matches the published versio