The Swift gamma-ray burst GRB 050422     

A. P. Beardmore  K. L. Page  P. T. O'Brien  J. P. Osborne  S. Kobayashi  B. Zhang  D. N. Burrows  M. Capalbi  M. R. Goad  O. Godet  J. E. Hill  V. La Parola  F. Marshall  A. A. Wells 《Monthly notices of the Royal Astronomical Society》2007,374(4):1473-1478

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Continuous monitoring of near-bottom mesoplankton communities in the East China Sea during a series of typhoons     

Mary M. Grossmann  Scott M. Gallager  Satoshi Mitarai 《Journal of Oceanography》2015,71(1):115-124

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Farm income,inequality, and poverty among farm families of a flood-prone area in Bangladesh: climate change vulnerability assessment     

Alamgir  Md. Shah  Furuya  Jun  Kobayashi  Shintaro  Mostafiz  Rubaiya Binte  Ahmed  Md. Rashid 《GeoJournal》2021,86(6):2861-2885

GeoJournal - This paper examines the farm income differences, income inequality of farm households, parameters of income variability that ascertain vulnerability levels, and cost-income variability...  相似文献   

Liverpool telescope 2: a new robotic facility for rapid transient follow-up     

C. M. Copperwheat  I. A. Steele  R. M. Barnsley  S. D. Bates  D. Bersier  M. F. Bode  D. Carter  N. R. Clay  C. A. Collins  M. J. Darnley  C. J. Davis  C. M. Gutierrez  D. J. Harman  P. A. James  J. H. Knapen  S. Kobayashi  J. M. Marchant  P. A. Mazzali  C. J. Mottram  C. G. Mundell  A. Newsam  A. Oscoz  E. Palle  A. Piascik  R. Rebolo  R. J. Smith 《Experimental Astronomy》2015,39(1):119-165

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Wavenumber spectra of planetary-scale disturbances in the Mars atmosphere     

Takeshi Imamura  Hiroko Kobayashi 《Icarus》2009,199(2):286-294

Wavenumber spectra of the martian atmosphere covering zonal wavenumbers s=1-6 were obtained as a function of latitude and season for the first time from the temperatures measured by the Thermal Emission Spectrometer onboard the Mars Global Surveyor. The stationary component tends to peak at s=2, where the martian topography has large amplitude, and drops rapidly at higher wavenumbers. The transient component in the middle and high latitudes tends to peak at s=1, which is lower than the most unstable wavenumber based on linear theories, and exhibits spectral slopes much flatter than the stationary component. In the equatorial region, the spectra of the transient component are almost flat, indicating that the organization of large-scale structures is less efficient in this region. The spectral shapes are similar between the 0.5 and 2.2 hPa surfaces, except that the slopes are slightly steeper at 0.5 than at 2.2 hPa, probably due to selective vertical transmission at low wavenumbers. The seasonal variation is relatively large in the middle and high latitudes, where the maximum power occurs in winter and the minimum occurs in summer, with an exception that the transient component is maximum in spring in the southern hemisphere. Intensification of s=1 transient waves is observed around the period of the initiation of global dust storms.  相似文献   

Capability of the penetrator seismometer system for lunar seismic event observation   总被引：2，自引：0，他引：2  

R. Yamada  I. Yamada  S. Tanaka  N. Kobayashi  Y. Ishihara  K. Yomogida  A. Fujimura 《Planetary and Space Science》2009,57(7):751-763

We developed a seismometer system for a hard landing “penetrator” probe in the course of the former Japanese LUNAR-A project to deploy new seismic stations on the Moon. The penetrator seismometer system (PSS) consists of two short-period sensor components, a two-axis gimbal mechanism for orientation, and measurement electronics. To carry out seismic observations on the Moon using the penetrator, the seismometer system has to function properly in a lunar environment after a hard landing (impact acceleration of about 8000 G), and requires a signal-to-noise ratio to detect lunar seismic events. We evaluated whether the PSS could satisfactorily observe seismic events on the Moon by investigating the frequency response, noise level, and response to ground motion of our instrument in a simulated lunar environment after a simulated impact test. Our results indicate that the newly developed seismometer system can function properly after impact and is sensitive enough to detect seismic events on the Moon. Using this PSS, new seismic data from the Moon can be obtained during future lunar missions.  相似文献   

Photoluminescence of baratovite and katayamalite     

Aierken Sidike  S. Kobayashi  Heng-Jiang Zhu  I. Kusachi  N. Yamashita 《Physics and Chemistry of Minerals》2010,37(10):705-710

The photoluminescence (PL) and optical excitation spectra of baratovite in aegirine syenite from Dara-i-Pioz, Tien Shan Mts., Tajikistan and katayamalite in aegirine syenite from Iwagi Islet, Ehime, Japan were obtained at 300 and 80 K. Under short wave (253.7 nm) ultraviolet light, baratovite and katayamalite exhibited bright blue-white luminescence. The PL spectrum of baratovite at 300 K consisted of a wide band with a peak at approximately 406 nm and a full width at half maximum (FWHM) of approximately 6.32k cm⁻¹. The excitation spectrum of the blue-white luminescence from baratovite at 300 K consisted of a prominent band with a peak at approximately 250 nm. The PL and excitation spectra of katayamalite were similar to those of baratovite. The luminescence from these minerals was attributed to the intrinsic luminescence from the TiO₆ center.  相似文献   

Fragmentation model dependence of collision cascades     

Hiroshi Kobayashi  Hidekazu Tanaka 《Icarus》2010,206(2):735-746

Mass depletion of bodies through successive collisional disruptions (i.e., collision cascade) is one of the most important processes in the studies of the asteroids belt, the Edgeworth-Kuiper belt, debris disks, and planetary formation. The collisional disruption is divided into two types, i.e., catastrophic disruption and cratering. Although some studies of the collision cascades neglected the effect of cratering, it is unclear which type of disruption makes a dominant contribution to the collision cascades. In the present study, we construct a simple outcome model describing both catastrophic disruption and cratering, which has some parameters characterizing the total ejecta mass, the mass of the largest fragment, and the power-law exponent of the size distribution of fragments. Using this simple outcome model with parameters, we examine the model dependence of the mass depletion time in collision cascades for neglect of coalescence of colliding bodies due to high collisional velocities. We find the cratering collisions are much more effective in collision cascades than collisions with catastrophic disruption in a wide region of the model parameters. It is also found that the mass depletion time in collision cascades is mainly governed by the total ejecta mass and almost insensitive to the mass of the largest fragment and the power-law exponent of fragments for a realistic parameter region. The total ejecta mass is usually determined by the ratio of the impact energy divided by the target mass (i.e. Q-value) to its threshold value for catastrophic disruption, as well as in our simple model. We derive a mass depletion time in collision cascades, which is determined by of the high-mass end of collision cascades. The mass depletion time derived with our model would be applicable to debris disks and planetary formation.  相似文献   

A trial for monitoring temporal variation of seismic velocity using an ACROSS system   总被引：4，自引：0，他引：4  

Koshun Yamaoka  Takahiro Kunitomo  Koji Miyakawa  Kazunori Kobayashi  Mineo Kumazawa 《Island Arc》2001,10(3-4):336-347

Abstract The temporal variation of seismic velocity near the Nojima Fault, which ruptured during the 1995 Kobe earthquake (Hyogo-ken Nanbu earthquake), was detected using an accurately controlled routine-operated seismic source (ACROSS). The source generates elastic waves by a centrifugal force of an eccentric mass rotating around an axis. The mass is driven with an AC servomotor whose angular position is accurately controlled with reference to a very accurate global positioning system (GPS) clock. The error of the mass' position is less than 0.002 radian and does not accumulate. As a result, the source generates sinusoidal waves of very narrow spectral peaks enabling their detection with an excellent signal-to-noise ratio. Although the stability of the rotation is quite excellent, a large daily variation was found, which seems to be caused by changes in atmospheric temperature. The daily variation was 10% in amplitude and 0.1 radian in phase of the signal observed at the 800 m borehole seismometer. A significant variation was found to be due to that of coupling between the rotational source and the foundation made of reinforced concrete in which the source was situated. In order to make a correction on the signal of the 800 m borehole seismometer, the vibration of the foundation was measured and modeled assuming a rigid body movement. The correction successfully reduced the daily variation by approximately 90%, resulting in a variation of 1% in amplitude and 0.01 radian in phase. The phase variation of 0.01 radian corresponds to 100 μs and less than 0.1% in velocity over 1000 m between the source and the receiver.  相似文献   

Garnet-amphibolites at Yokokawa in the Abukuma metamorphic belt,Japan     

Satoshi Kanisawa 《Contributions to Mineralogy and Petrology》1969,20(2):164-176

The mineralogy and petrochemistry of the garnet-amphibolites from the highgrade part of the Abukuma metamorphic belt have been studied, using five analyses of rocks, five of hornblendes, three of garnets and one analysis of cummingtonite, Garnetiferous amphibolites are rich in Fe, whereas non-garnetiferous ones are rich in Mg, especially in cummingtonite-amphibolite. The chemical composition of hornblendes associated with garnet is pargasitic and rich in FeO and poor in CaO, but that of non-garnetiferous rocks is rich in MgO. The garnets are rich in almandine molecule. Mg/Mg + Fe²⁺ ratios of both hornblendes and garnets correspond with those of the host rocks. The development of garnet in the Adirondack metabasites belonging to the upper almandine-amphibolite and granulite facies is observed in Mg-rich rocks as well as in Fe-rich rocks, in which both garnet and hornblende are rich in Mg respectively. However, under the conditions of the andalusite-sillimanite type metamorphism as shown in the Abukuma Plateau, Fe-rich garnet occurs in Fe-rich basic rocks, but cummingtonite occurs in Mg-rich ones instead of Mg-rich garnet. Finally, the problem of polymetamorphism is discussed. The cummingtonite-amphibolite may be the product of polymetamorphism, and Mg-rich garnet which had been present previously was decomposed to cummingtonite and plagioclase by the subsequent regional metamorphism of andalusite-sillimanite type.  相似文献