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1.
Kazutaka Yamaoka Yoshihiro Ueda Hajime Inoue Fumiaki Nagase Ken Ebisawa Taro Kotani Yasuo Tanaka 《Astrophysics and Space Science》2001,276(1):19-22
We summarize the ASCA observations of the two Galactic superluminal sources GRO J1655–40 and GRS 1915+105, focusing on theabsorption line features.The high spectroscopic capability of ASCA enabled us to detectiron-K absorption line features from both objects. This is direct evidence for the presence of highly ionized plasma in a non-spherical configuration around a black hole, and is considered to be a unique signature of superluminal jet systems. The candidate of the line-absorber would be a part of an accretion disk at a distance of 109-11 cm from the central X-ray source. 相似文献
2.
Energy-dependent pulse profiles from the X-ray pulsar 4U1626-67, observed with Tenma in May 1983, were studied using an anisotropic radiation transfer model in an accretion column on a strongly magnetized neutron star. The result indicates that the strength of the magnetic field is about 8×1012 G at the surface of the neutron star.Paper presented at the IAU Third Asian-Pacific Regional Meeting, held in Kyoto, Japan, between 30 September–6 October, 1984. 相似文献
3.
Takahiro Kuribayashi Asami Sano-Furukawa Toshiro Nagase 《Physics and Chemistry of Minerals》2014,41(4):303-312
Pressure-induced phase transition of δ-AlOOH was confirmed between 6.1 and 8.2 GPa by using a single-crystal synchrotron X-ray diffraction method. The phase transition is reversible and unquenchable. Results from analysis of the distribution of X-ray diffraction intensities at 8.2 GPa reveal an additional systematic, absence of k + l odd for 0kl in comparison with h + l odd for h0l observed prior to the phase transition (space group, P21 nm). The space group of the post-transition phase should be Pnnm or Pnn2 to satisfy the systematic absence rule. Crystal structure refinements of the post-transition phase conducted for the three models (Pnnm, Pnn2, and P21 nm) indicate that the space group of the post-transition phase is Pnnm. The O–O distance of hydrogen bond in the post-transition phase at 8.2 GPa is 2.439(6) Å and is significantly longer than the predicted distance (2.366 Å) of the hydrogen bond symmetrization in δ-AlOOH. The H distribution in the post-transition phase would display a fully disordered hydrogen bond pattern. 相似文献
4.
Michael D. Audley † Fumiaki Nagase Kazuhisa Mitsuda Lorella Angelini Richard L. Kelley 《Monthly notices of the Royal Astronomical Society》2006,367(3):1147-1154
We report on two ASCA observations of the high-mass X-ray binary pulsar OAO 1657−415. A short observation near mid-eclipse caught the source in a low-intensity state, with a weak continuum and iron emission dominated by the 6.4-keV fluorescent line. A later, longer observation found the source in a high-intensity state and covered the uneclipsed through mid-eclipse phases. In the high-intensity state, the non-eclipse spectrum has an absorbed continuum component due to scattering by material near the pulsar and 80 per cent of the fluorescent iron emission comes from less than 19 light-second away from the pulsar. We find a dust-scattered X-ray halo whose intensity decays through the eclipse. We use this halo to estimate the distance to the source as 7.1 ± 1.3 kpc. 相似文献
5.
LIU Hanlong DAI Huichao Susumu IAI
Professor Geotechnical Engineering Research Institute Hohai University Nanjing China.
Senior Engineer China Yangtze Three Gorges Project Development Corporation Yichang China.
Doctor Port Harbour Research Institute Ministry of Transport Nagase Japan. 《中国海洋工程》1999,(1)
—Effective stress analysis is performed to evaluate the residual displacement of a caissonquaywall during 1994 Hokkaido-Toho-Oki Earthquake and 1993 Kushiro-Oki Earthquake.Theconstitutive model used in this study is a multiple shear mechanism type defined in strain space and cantake into account the effect of rotation of principal stress axis.The earthquake accelerations recorded atthe outcropping rock during the earthquake are used as input bedrock motion.The results of finite ele-ment analysis are in good agreement with the observed behaviour of the quaywall.The analysis also indi-cates that liquefaction and high excess pore water pressure have a significant effect on the deformation ofthe caisson.Soil improvement is speculated as the most reliable measures against liquefaction.The influ-ence of soil improvement and the reasonable improved area are discussed in the paper. 相似文献
6.
Y. Kudoh T. Nagase S. Sasaki M. Tanaka M. Kanzaki 《Physics and Chemistry of Minerals》1995,22(5):295-299
The structure of phase F, a non-stoichiometric hydrous silicate synthesized in a uniaxial, split-sphere, multi-anvil apparatus at conditions of 17 GPa and 1000° C, has been solved and refined in space group P63cm, using synchrotron X-ray data for a single crystal of a size 18 × 24 × 30 μm. The composition and unit cell for phase F are Mg3.35Si5.51H7.26O18, a=5.073(3) Å, c=14.013(9) Å, 7= 312.3(5) Å3. The structure contains layers with many similarities to superhydrous phase B. The layers of oxygen atoms are stacked in the ABCBAC-type double cubic closest packing arrangement. The bulk modulus of phase F was estimated from the structural and compositional relationship to superhydrous phase B and periclase. 相似文献
7.
S. Miyoshi S. Haykawa H. Kunieda F. Nagase Y. Tawara 《Astrophysics and Space Science》1986,119(1):185-190
In order to investigate the structure and mechanism of active galactic nuclei through X-ray observation, detailed energy spectra are examined with the gas scintillation proportional counters on board TENMA. For three selected objects, PKS 2155-304, Centaurus A and IC 4329 A, the observational results in the intensity variation, the spectral shapes and the iron line features are presented.Paper presented at the IAU Third Asian-Pacific Regional Meeting, held in Kyoto, Japan, between 30 September–6 October, 1984. 相似文献
8.
9.
F. Nagase 《Journal of Astrophysics and Astronomy》2002,23(1-2):59-65
Several new features of X-ray binary pulsars are revealed from recent observations with ASCA, RXTE, BeppoSAX and other X-ray
observatories. Among these, I will review in this paper some recent progress in spectroscopic studies of accreting X-ray pulsars
in binary systems (XBPs). First, I will discuss soft excess features observed in the energy spectra of XBPs and propose that
it is a common feature for various subclasses of XBPs. Next I will present some recent results of high resolution spectroscopy
with ASCA and Chandra. 相似文献
10.
A rocket observation of cosmic soft X-rays suggests the existence of transient, recurrent soft X-ray sources which are found variable during the flight time of the rocket. Some of the soft X-ray sources thus far reported are considered to be of this time. These sources are listed in Table I, and their positions are shown in Figure 2.Paper presented at the COSPAR Symposium on Fast Transients in X- and Gamma-Rays, held at Varna, Bulgaria, 29–31 May, 1975. 相似文献