The Experts below are selected from a list of 231 Experts worldwide ranked by ideXlab platform
Yoshiaki Ishihara - One of the best experts on this subject based on the ideXlab platform.
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Viscoelastic deformation of lunar impact basins: Implications for heterogeneity in the deep crustal paleo‐thermal state and Radioactive Element concentration
Journal of Geophysical Research: Planets, 2013Co-Authors: Shunichi Kamata, Seiji Sugita, Yoshiaki Ishihara, Yuji Harada, Tomokatsu Morota, Noriyuki Namiki, Takahiro Iwata, Hideo Hanada, Yutaka Abe, Hiroshi ArakiAbstract:[1] Diverse geological characteristics found for the three major lunar provinces (i.e., the Feldspathic Highlands Terrane (FHT), the South Pole-Aitken Terrane (SPAT), and the Procerallum KREEP Terrane (PKT)) strongly suggest their distinctly different thermal histories. Quantitative differences among these provinces in their early thermal histories and crustal Radioactive Element concentrations, however, are highly unknown. One of the few observables that retain a record of the ancient lunar thermal structure is the viscoelastic state of impact basins. This study investigates the long-term evolution of basin structures using global lunar gravity field data obtained by Kaguya tracking and derives constraints for (1) the paleo-thermal state of impact basins and for (2) crustal column-averaged Radioactive Element concentrations for each province. Our calculation results indicate that impact basins in the central anorthositic region of the FHT (i.e., the FHT-An) require a very cold interior ( dT ∕ dr ≤ 20 K km − 1 on the surface). This result strongly suggests that the deep portion of the thick farside highlands crust is highly depleted in Radioactive Elements (Th ≤ 0.5 ppm), indicating that the Th-rich SPA basin floor crust is clearly different from the lower crust underneath the FHT-An and cannot be accounted for by simple exposure of the lower crust. Our analysis also indicates that the observed basin structure allows as high as ∼ 6 ppm of column-averaged Th concentration in the crust inside the PKT. These results indicate that Radioactive Element concentrations deep in the crust probably vary greatly region by region, similarly to those observed on the surface.
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viscoelastic deformation of lunar impact basins implications for heterogeneity in the deep crustal paleo thermal state and Radioactive Element concentration
Journal of Geophysical Research, 2013Co-Authors: Shunichi Kamata, Seiji Sugita, Yoshiaki Ishihara, Yuji Harada, Tomokatsu Morota, Noriyuki Namiki, Takahiro Iwata, Hideo Hanada, Hiroshi ArakiAbstract:[1] Diverse geological characteristics found for the three major lunar provinces (i.e., the Feldspathic Highlands Terrane (FHT), the South Pole-Aitken Terrane (SPAT), and the Procerallum KREEP Terrane (PKT)) strongly suggest their distinctly different thermal histories. Quantitative differences among these provinces in their early thermal histories and crustal Radioactive Element concentrations, however, are highly unknown. One of the few observables that retain a record of the ancient lunar thermal structure is the viscoelastic state of impact basins. This study investigates the long-term evolution of basin structures using global lunar gravity field data obtained by Kaguya tracking and derives constraints for (1) the paleo-thermal state of impact basins and for (2) crustal column-averaged Radioactive Element concentrations for each province. Our calculation results indicate that impact basins in the central anorthositic region of the FHT (i.e., the FHT-An) require a very cold interior ( dT ∕ dr ≤ 20 K km − 1 on the surface). This result strongly suggests that the deep portion of the thick farside highlands crust is highly depleted in Radioactive Elements (Th ≤ 0.5 ppm), indicating that the Th-rich SPA basin floor crust is clearly different from the lower crust underneath the FHT-An and cannot be accounted for by simple exposure of the lower crust. Our analysis also indicates that the observed basin structure allows as high as ∼ 6 ppm of column-averaged Th concentration in the crust inside the PKT. These results indicate that Radioactive Element concentrations deep in the crust probably vary greatly region by region, similarly to those observed on the surface.
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viscoelastic deformation of lunar impact basins implications for heterogeneity in the deep crustal paleo thermal state and Radioactive Element concentration
Journal of Geophysical Research, 2013Co-Authors: Shunichi Kamata, Seiji Sugita, Yoshiaki Ishihara, Yuji Harada, Tomokatsu Morota, Noriyuki Namiki, Takahiro Iwata, Yutaka Abe, Hideo HanadaAbstract:[1] Diverse geological characteristics found for the three major lunar provinces (i.e., the Feldspathic Highlands Terrane (FHT), the South Pole-Aitken Terrane (SPAT), and the Procerallum KREEP Terrane (PKT)) strongly suggest their distinctly different thermal histories. Quantitative differences among these provinces in their early thermal histories and crustal Radioactive Element concentrations, however, are highly unknown. One of the few observables that retain a record of the ancient lunar thermal structure is the viscoelastic state of impact basins. This study investigates the long-term evolution of basin structures using global lunar gravity field data obtained by Kaguya tracking and derives constraints for (1) the paleo-thermal state of impact basins and for (2) crustal column-averaged Radioactive Element concentrations for each province. Our calculation results indicate that impact basins in the central anorthositic region of the FHT (i.e., the FHT-An) require a very cold interior ( dT ∕ dr ≤ 20 K km − 1 on the surface). This result strongly suggests that the deep portion of the thick farside highlands crust is highly depleted in Radioactive Elements (Th ≤ 0.5 ppm), indicating that the Th-rich SPA basin floor crust is clearly different from the lower crust underneath the FHT-An and cannot be accounted for by simple exposure of the lower crust. Our analysis also indicates that the observed basin structure allows as high as ∼ 6 ppm of column-averaged Th concentration in the crust inside the PKT. These results indicate that Radioactive Element concentrations deep in the crust probably vary greatly region by region, similarly to those observed on the surface.
S Van Eck - One of the best experts on this subject based on the ideXlab platform.
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transition probabilities in singly ionized promethium and the identification of pm ii lines in przybylski s star and hr 465
Monthly Notices of the Royal Astronomical Society, 2007Co-Authors: V. Fivet, Pascal Quinet, Emile Biémont, Alain Jorissen, A V Yushchenko, S Van EckAbstract:The first theoretical transition probabilities are obtained for a set of 46 Pm II transitions of astrophysical interest. These data fill in a gap in astrophysics and will allow to establish, on a firmer basis, the presence of some lines of this Radioactive Element in the spectra of chemically peculiar stars and, consequently, a quantitative investigation of the stellar Pm abundance. A search for Pm II lines in Przybylski’s star (HD 101065) and in HR 465 is reported and discussed, supporting the detection of this ion. A more detailed quantitative analysis is awaiting the availability of dedicated model atmospheres for these stars.
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Transition probabilities in singly ionized promethium and the identification of Pm ii lines in Przybylski's star and HR 465★
Monthly Notices of the Royal Astronomical Society, 2007Co-Authors: V. Fivet, Pascal Quinet, Emile Biémont, Alain Jorissen, A V Yushchenko, S Van EckAbstract:The first theoretical transition probabilities are obtained for a set of 46 Pm II transitions of astrophysical interest. These data fill in a gap in astrophysics and will allow to establish, on a firmer basis, the presence of some lines of this Radioactive Element in the spectra of chemically peculiar stars and, consequently, a quantitative investigation of the stellar Pm abundance. A search for Pm II lines in Przybylski’s star (HD 101065) and in HR 465 is reported and discussed, supporting the detection of this ion. A more detailed quantitative analysis is awaiting the availability of dedicated model atmospheres for these stars.
Shunichi Kamata - One of the best experts on this subject based on the ideXlab platform.
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Viscoelastic deformation of lunar impact basins: Implications for heterogeneity in the deep crustal paleo‐thermal state and Radioactive Element concentration
Journal of Geophysical Research: Planets, 2013Co-Authors: Shunichi Kamata, Seiji Sugita, Yoshiaki Ishihara, Yuji Harada, Tomokatsu Morota, Noriyuki Namiki, Takahiro Iwata, Hideo Hanada, Yutaka Abe, Hiroshi ArakiAbstract:[1] Diverse geological characteristics found for the three major lunar provinces (i.e., the Feldspathic Highlands Terrane (FHT), the South Pole-Aitken Terrane (SPAT), and the Procerallum KREEP Terrane (PKT)) strongly suggest their distinctly different thermal histories. Quantitative differences among these provinces in their early thermal histories and crustal Radioactive Element concentrations, however, are highly unknown. One of the few observables that retain a record of the ancient lunar thermal structure is the viscoelastic state of impact basins. This study investigates the long-term evolution of basin structures using global lunar gravity field data obtained by Kaguya tracking and derives constraints for (1) the paleo-thermal state of impact basins and for (2) crustal column-averaged Radioactive Element concentrations for each province. Our calculation results indicate that impact basins in the central anorthositic region of the FHT (i.e., the FHT-An) require a very cold interior ( dT ∕ dr ≤ 20 K km − 1 on the surface). This result strongly suggests that the deep portion of the thick farside highlands crust is highly depleted in Radioactive Elements (Th ≤ 0.5 ppm), indicating that the Th-rich SPA basin floor crust is clearly different from the lower crust underneath the FHT-An and cannot be accounted for by simple exposure of the lower crust. Our analysis also indicates that the observed basin structure allows as high as ∼ 6 ppm of column-averaged Th concentration in the crust inside the PKT. These results indicate that Radioactive Element concentrations deep in the crust probably vary greatly region by region, similarly to those observed on the surface.
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viscoelastic deformation of lunar impact basins implications for heterogeneity in the deep crustal paleo thermal state and Radioactive Element concentration
Journal of Geophysical Research, 2013Co-Authors: Shunichi Kamata, Seiji Sugita, Yoshiaki Ishihara, Yuji Harada, Tomokatsu Morota, Noriyuki Namiki, Takahiro Iwata, Hideo Hanada, Hiroshi ArakiAbstract:[1] Diverse geological characteristics found for the three major lunar provinces (i.e., the Feldspathic Highlands Terrane (FHT), the South Pole-Aitken Terrane (SPAT), and the Procerallum KREEP Terrane (PKT)) strongly suggest their distinctly different thermal histories. Quantitative differences among these provinces in their early thermal histories and crustal Radioactive Element concentrations, however, are highly unknown. One of the few observables that retain a record of the ancient lunar thermal structure is the viscoelastic state of impact basins. This study investigates the long-term evolution of basin structures using global lunar gravity field data obtained by Kaguya tracking and derives constraints for (1) the paleo-thermal state of impact basins and for (2) crustal column-averaged Radioactive Element concentrations for each province. Our calculation results indicate that impact basins in the central anorthositic region of the FHT (i.e., the FHT-An) require a very cold interior ( dT ∕ dr ≤ 20 K km − 1 on the surface). This result strongly suggests that the deep portion of the thick farside highlands crust is highly depleted in Radioactive Elements (Th ≤ 0.5 ppm), indicating that the Th-rich SPA basin floor crust is clearly different from the lower crust underneath the FHT-An and cannot be accounted for by simple exposure of the lower crust. Our analysis also indicates that the observed basin structure allows as high as ∼ 6 ppm of column-averaged Th concentration in the crust inside the PKT. These results indicate that Radioactive Element concentrations deep in the crust probably vary greatly region by region, similarly to those observed on the surface.
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viscoelastic deformation of lunar impact basins implications for heterogeneity in the deep crustal paleo thermal state and Radioactive Element concentration
Journal of Geophysical Research, 2013Co-Authors: Shunichi Kamata, Seiji Sugita, Yoshiaki Ishihara, Yuji Harada, Tomokatsu Morota, Noriyuki Namiki, Takahiro Iwata, Yutaka Abe, Hideo HanadaAbstract:[1] Diverse geological characteristics found for the three major lunar provinces (i.e., the Feldspathic Highlands Terrane (FHT), the South Pole-Aitken Terrane (SPAT), and the Procerallum KREEP Terrane (PKT)) strongly suggest their distinctly different thermal histories. Quantitative differences among these provinces in their early thermal histories and crustal Radioactive Element concentrations, however, are highly unknown. One of the few observables that retain a record of the ancient lunar thermal structure is the viscoelastic state of impact basins. This study investigates the long-term evolution of basin structures using global lunar gravity field data obtained by Kaguya tracking and derives constraints for (1) the paleo-thermal state of impact basins and for (2) crustal column-averaged Radioactive Element concentrations for each province. Our calculation results indicate that impact basins in the central anorthositic region of the FHT (i.e., the FHT-An) require a very cold interior ( dT ∕ dr ≤ 20 K km − 1 on the surface). This result strongly suggests that the deep portion of the thick farside highlands crust is highly depleted in Radioactive Elements (Th ≤ 0.5 ppm), indicating that the Th-rich SPA basin floor crust is clearly different from the lower crust underneath the FHT-An and cannot be accounted for by simple exposure of the lower crust. Our analysis also indicates that the observed basin structure allows as high as ∼ 6 ppm of column-averaged Th concentration in the crust inside the PKT. These results indicate that Radioactive Element concentrations deep in the crust probably vary greatly region by region, similarly to those observed on the surface.
Hiroshi Araki - One of the best experts on this subject based on the ideXlab platform.
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Viscoelastic deformation of lunar impact basins: Implications for heterogeneity in the deep crustal paleo‐thermal state and Radioactive Element concentration
Journal of Geophysical Research: Planets, 2013Co-Authors: Shunichi Kamata, Seiji Sugita, Yoshiaki Ishihara, Yuji Harada, Tomokatsu Morota, Noriyuki Namiki, Takahiro Iwata, Hideo Hanada, Yutaka Abe, Hiroshi ArakiAbstract:[1] Diverse geological characteristics found for the three major lunar provinces (i.e., the Feldspathic Highlands Terrane (FHT), the South Pole-Aitken Terrane (SPAT), and the Procerallum KREEP Terrane (PKT)) strongly suggest their distinctly different thermal histories. Quantitative differences among these provinces in their early thermal histories and crustal Radioactive Element concentrations, however, are highly unknown. One of the few observables that retain a record of the ancient lunar thermal structure is the viscoelastic state of impact basins. This study investigates the long-term evolution of basin structures using global lunar gravity field data obtained by Kaguya tracking and derives constraints for (1) the paleo-thermal state of impact basins and for (2) crustal column-averaged Radioactive Element concentrations for each province. Our calculation results indicate that impact basins in the central anorthositic region of the FHT (i.e., the FHT-An) require a very cold interior ( dT ∕ dr ≤ 20 K km − 1 on the surface). This result strongly suggests that the deep portion of the thick farside highlands crust is highly depleted in Radioactive Elements (Th ≤ 0.5 ppm), indicating that the Th-rich SPA basin floor crust is clearly different from the lower crust underneath the FHT-An and cannot be accounted for by simple exposure of the lower crust. Our analysis also indicates that the observed basin structure allows as high as ∼ 6 ppm of column-averaged Th concentration in the crust inside the PKT. These results indicate that Radioactive Element concentrations deep in the crust probably vary greatly region by region, similarly to those observed on the surface.
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viscoelastic deformation of lunar impact basins implications for heterogeneity in the deep crustal paleo thermal state and Radioactive Element concentration
Journal of Geophysical Research, 2013Co-Authors: Shunichi Kamata, Seiji Sugita, Yoshiaki Ishihara, Yuji Harada, Tomokatsu Morota, Noriyuki Namiki, Takahiro Iwata, Hideo Hanada, Hiroshi ArakiAbstract:[1] Diverse geological characteristics found for the three major lunar provinces (i.e., the Feldspathic Highlands Terrane (FHT), the South Pole-Aitken Terrane (SPAT), and the Procerallum KREEP Terrane (PKT)) strongly suggest their distinctly different thermal histories. Quantitative differences among these provinces in their early thermal histories and crustal Radioactive Element concentrations, however, are highly unknown. One of the few observables that retain a record of the ancient lunar thermal structure is the viscoelastic state of impact basins. This study investigates the long-term evolution of basin structures using global lunar gravity field data obtained by Kaguya tracking and derives constraints for (1) the paleo-thermal state of impact basins and for (2) crustal column-averaged Radioactive Element concentrations for each province. Our calculation results indicate that impact basins in the central anorthositic region of the FHT (i.e., the FHT-An) require a very cold interior ( dT ∕ dr ≤ 20 K km − 1 on the surface). This result strongly suggests that the deep portion of the thick farside highlands crust is highly depleted in Radioactive Elements (Th ≤ 0.5 ppm), indicating that the Th-rich SPA basin floor crust is clearly different from the lower crust underneath the FHT-An and cannot be accounted for by simple exposure of the lower crust. Our analysis also indicates that the observed basin structure allows as high as ∼ 6 ppm of column-averaged Th concentration in the crust inside the PKT. These results indicate that Radioactive Element concentrations deep in the crust probably vary greatly region by region, similarly to those observed on the surface.
Hideo Hanada - One of the best experts on this subject based on the ideXlab platform.
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Viscoelastic deformation of lunar impact basins: Implications for heterogeneity in the deep crustal paleo‐thermal state and Radioactive Element concentration
Journal of Geophysical Research: Planets, 2013Co-Authors: Shunichi Kamata, Seiji Sugita, Yoshiaki Ishihara, Yuji Harada, Tomokatsu Morota, Noriyuki Namiki, Takahiro Iwata, Hideo Hanada, Yutaka Abe, Hiroshi ArakiAbstract:[1] Diverse geological characteristics found for the three major lunar provinces (i.e., the Feldspathic Highlands Terrane (FHT), the South Pole-Aitken Terrane (SPAT), and the Procerallum KREEP Terrane (PKT)) strongly suggest their distinctly different thermal histories. Quantitative differences among these provinces in their early thermal histories and crustal Radioactive Element concentrations, however, are highly unknown. One of the few observables that retain a record of the ancient lunar thermal structure is the viscoelastic state of impact basins. This study investigates the long-term evolution of basin structures using global lunar gravity field data obtained by Kaguya tracking and derives constraints for (1) the paleo-thermal state of impact basins and for (2) crustal column-averaged Radioactive Element concentrations for each province. Our calculation results indicate that impact basins in the central anorthositic region of the FHT (i.e., the FHT-An) require a very cold interior ( dT ∕ dr ≤ 20 K km − 1 on the surface). This result strongly suggests that the deep portion of the thick farside highlands crust is highly depleted in Radioactive Elements (Th ≤ 0.5 ppm), indicating that the Th-rich SPA basin floor crust is clearly different from the lower crust underneath the FHT-An and cannot be accounted for by simple exposure of the lower crust. Our analysis also indicates that the observed basin structure allows as high as ∼ 6 ppm of column-averaged Th concentration in the crust inside the PKT. These results indicate that Radioactive Element concentrations deep in the crust probably vary greatly region by region, similarly to those observed on the surface.
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viscoelastic deformation of lunar impact basins implications for heterogeneity in the deep crustal paleo thermal state and Radioactive Element concentration
Journal of Geophysical Research, 2013Co-Authors: Shunichi Kamata, Seiji Sugita, Yoshiaki Ishihara, Yuji Harada, Tomokatsu Morota, Noriyuki Namiki, Takahiro Iwata, Hideo Hanada, Hiroshi ArakiAbstract:[1] Diverse geological characteristics found for the three major lunar provinces (i.e., the Feldspathic Highlands Terrane (FHT), the South Pole-Aitken Terrane (SPAT), and the Procerallum KREEP Terrane (PKT)) strongly suggest their distinctly different thermal histories. Quantitative differences among these provinces in their early thermal histories and crustal Radioactive Element concentrations, however, are highly unknown. One of the few observables that retain a record of the ancient lunar thermal structure is the viscoelastic state of impact basins. This study investigates the long-term evolution of basin structures using global lunar gravity field data obtained by Kaguya tracking and derives constraints for (1) the paleo-thermal state of impact basins and for (2) crustal column-averaged Radioactive Element concentrations for each province. Our calculation results indicate that impact basins in the central anorthositic region of the FHT (i.e., the FHT-An) require a very cold interior ( dT ∕ dr ≤ 20 K km − 1 on the surface). This result strongly suggests that the deep portion of the thick farside highlands crust is highly depleted in Radioactive Elements (Th ≤ 0.5 ppm), indicating that the Th-rich SPA basin floor crust is clearly different from the lower crust underneath the FHT-An and cannot be accounted for by simple exposure of the lower crust. Our analysis also indicates that the observed basin structure allows as high as ∼ 6 ppm of column-averaged Th concentration in the crust inside the PKT. These results indicate that Radioactive Element concentrations deep in the crust probably vary greatly region by region, similarly to those observed on the surface.
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viscoelastic deformation of lunar impact basins implications for heterogeneity in the deep crustal paleo thermal state and Radioactive Element concentration
Journal of Geophysical Research, 2013Co-Authors: Shunichi Kamata, Seiji Sugita, Yoshiaki Ishihara, Yuji Harada, Tomokatsu Morota, Noriyuki Namiki, Takahiro Iwata, Yutaka Abe, Hideo HanadaAbstract:[1] Diverse geological characteristics found for the three major lunar provinces (i.e., the Feldspathic Highlands Terrane (FHT), the South Pole-Aitken Terrane (SPAT), and the Procerallum KREEP Terrane (PKT)) strongly suggest their distinctly different thermal histories. Quantitative differences among these provinces in their early thermal histories and crustal Radioactive Element concentrations, however, are highly unknown. One of the few observables that retain a record of the ancient lunar thermal structure is the viscoelastic state of impact basins. This study investigates the long-term evolution of basin structures using global lunar gravity field data obtained by Kaguya tracking and derives constraints for (1) the paleo-thermal state of impact basins and for (2) crustal column-averaged Radioactive Element concentrations for each province. Our calculation results indicate that impact basins in the central anorthositic region of the FHT (i.e., the FHT-An) require a very cold interior ( dT ∕ dr ≤ 20 K km − 1 on the surface). This result strongly suggests that the deep portion of the thick farside highlands crust is highly depleted in Radioactive Elements (Th ≤ 0.5 ppm), indicating that the Th-rich SPA basin floor crust is clearly different from the lower crust underneath the FHT-An and cannot be accounted for by simple exposure of the lower crust. Our analysis also indicates that the observed basin structure allows as high as ∼ 6 ppm of column-averaged Th concentration in the crust inside the PKT. These results indicate that Radioactive Element concentrations deep in the crust probably vary greatly region by region, similarly to those observed on the surface.