Takafumi Matsui

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The Cretaceous-Paleogene boundary approximately 65.5 million years ago marks one of the three largest mass extinctions in the past 500 million years. The extinction event coincided with a large asteroid impact at Chicxulub, Mexico, and occurred within the time of Deccan flood basalt volcanism in India. Here, we synthesize records of the global stratigraphy(More)
High-velocity (-• 2 to-• 5 km/sec) impacts into octahedrite iron meteorites (Gibeon, El Sampal, and Arispe), steel, and iron targets were made at the NASA-Ames Vertical Gun Facility. The experiments clearly revealed the brittle behavior of meteorites at very low temperatures (<200 ø K) as indicated by spallation of the crater rim and the development of(More)
Cyanide compounds are amongst the most important molecules of the origin of life. Here, we demonstrate the importance of mid-size (0.1–1 km in diameter) hence frequent meteoritic impacts to the cyanide inventory on the early Earth. Subsequent aerodynamic ablation and chemical reactions with the ambient atmosphere after oblique impacts were investigated by(More)
Observing cloud and aerosol distributions and their optical and microphysical properties are one of important activities for the global climate change study, since the role of these particles and their interactive responses to the climate system are still in mystery. The Second generation Global Imager (SGLI) aboard the GCOM-C satellite is a follow-on(More)
Clouds and aerosols are known to play crucial roles in the climate system; however, they are also main sources of uncertainty in our knowledge, and especially large efforts are needed to evaluate their interactions (IPCC 2007). The Japan Aerospace Exploration Agency (JAXA) is carrying out the EarthCARE (Earth Clouds, Aerosols, and Radiation Explorer)(More)
Electrical properties of PECVD produced poly-Si photovoltaic layers on the various textured substrates showing the light trapping effect have been investigated using an AC-conductivity technique. From temperature dependence of electron (hole) conductivities using n-i-n (p-i-p) structures, the Fermi level of the poly-Si layer on the slightly textured(More)
Forsterite (Mg2SiO4) is one of the major planetary materials, and its behavior under extreme conditions is important to understand the interior structure of large planets, such as super-Earths, and large-scale planetary impact events. Previous shock compression measurements of forsterite indicate that it may melt below 200 GPa, but these measurements did(More)
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