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We propose a test of the gravitational time dilation in general relativity by long term clock comparison between two stations separated in height. The geopotential difference between the two National time keeping centers in China, Lintong (A)(A) and Beijing (B)(B) is around 4000 geopotential unit, which corresponds to the height difference of 400 m. Two clocks CACA and CBCB are fixed at stations A and B, respectively, which are synchronized at beginning by a portable clock C in a short time period with go-back synchronization approach. After one month, the clock C is again transported between A and B  , comparing the records of the keeping time by clocks CACA and CBCB, respectively. Calculations show that, after one month, the difference of the time durations between the clocks CACA and CBCB is around 121 ns, if general relativity is correct.  相似文献   

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We present medium resolution near-infrared host galaxy spectra of low redshift quasars, PG 0844+3490844+349 (z = 0.064), PG 1226+0231226+023 (z = 0.158), and PG 1426+0151426+015 (z = 0.086). The observations were done by using the Infrared Camera and Spectrograph (IRCS) at the Subaru 8.2 m telescope. The full width at half maximum of the point spread function was about 0.3 arcsec by operations of an adaptive optics system, which can effectively resolve the quasar spectra from the host galaxy spectra. We spent up to several hours per target and developed data reduction methods to reduce the systematic noises of the telluric emissions and absorptions. From the obtained spectra, we identified absorption features of Mg I (1.503 μm), Si I (1.589 μm) and CO (6-3) (1.619 μm), and measured the velocity dispersions of PG 0844+3490844+349 to be 132 ± 110 km s−1 and PG 1426+0151426+015 to be 264 ± 215 km s−1. By using an MBH–σMBHσ relation of elliptical galaxies, we derived the black hole (BH) mass of PG 0844+3490844+349, log(MBH/M)=7.7±5.5log(MBH/M)=7.7±5.5 and PG 1426+015,log(MBH/M)=9.0±7.51426+015,log(MBH/M)=9.0±7.5. These values are consistent with the BH mass values from broad emission lines with an assumption of a virial factor of 5.5.  相似文献   

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We study the propagation of energetic particles, accelerated by interplanetary shock waves, upstream of the shock. By using the appropriate propagator, we show that in the case of superdiffusive transport, the time profile of particles accelerated at a traveling planar shock is a power-law with slope 0<γ<10<γ<1, at variance with the exponential profile obtained for normal diffusion. By analyzing data sets of interplanetary shocks in the solar wind observed by the Ulysses and the Voyager 2 spacecraft, we find that the time profiles of energetic electrons correspond to power-laws, with slopes γ?0.30–0.98γ?0.300.98, implying a mean square displacement 〈Δx2〉∝tαΔx2tα, with α=2-γ>1α=2-γ>1, i.e., superdiffusion. In addition, the propagation of ions is also superdiffusive, with α=1.07–1.13α=1.071.13.  相似文献   

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An ion chemistry model is used to investigate the negative chlorine ion chemistry of the mesosphere for quiet ionospheric conditions. Model results are presented for high latitudes in February as well as for the equator in Summer. For nighttime, Cl-Cl-, Cl-Cl-(HCl), and NO3(HCl) are the most abundant chlorine anions in the mesosphere. The concentration of ClO3 depends significantly on its stability against collision-induced dissociation. In contrast to previous model predictions, the abundance of Cl-(H2O)Cl-(H2O) is small. For daytime, photoelectron detachment and photodissociation have pronounced impact on the negative chlorine ion chemistry in the mesosphere. The abundance of all anion cluster is considerably smaller than at night. While Cl-Cl- decreases in the upper mesosphere, its abundance increases at lower altitudes.  相似文献   

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Crossings of the magnetopause near the subsolar point are analyzed using data of THEMIS mission. Variations of the magnetic field near magnetopause measured by one of THEMIS satellites are studied and compared with simultaneous measurements in the solar wind by another THEMIS satellite. The time delay of the solar wind arrival at the subsolar point of the magnetopause is taken into account. 30 and 90 s averaging of the magnetic field in the magnetosheath is produced. The results of averaging are compared with the results of measurements in the solar wind before the bow shock and foreshock. It is shown, that BxBx component of the magnetic field near magnetopause is near to zero, which supports the possibility to consider the magnetopause as the tangential discontinuity. Comparatively good correlation of ByBy component in the solar wind and near the magnetopause is observed. The correlation of BzBz component near the magnetopause and IMF is practically absent, the sign of the BzBz near the subsolar point does not coincide with the sign of IMF BzBz in ∼30% cases.  相似文献   

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We describe an alternate way to estimate Broad Line Region (BLR) radii for type-1 AGN based on determination of physical conditions in the BLR under the assumption that the line emitting gas is photoionized by a central continuum source. We derive “diagnostic” intensity ratios involving UV lines Aliiiλλ1860, Siiii]λλ1892 and Civλλ1549 which enable us to compute the ionizing photon flux, and hence BLR radius from the ionization parameter definition. We compare our estimates of BLR radii with values independently obtained from reverberation monitoring of Hββ and, in a few cases, of C ivλλ1549. We analyze the interpretation of the photoionization estimates in the 4D eigenvector 1 context, and discuss in some detail the case of 3C 390.3. For this object we are able to provide not only the ionizing photon flux, but also an estimate of density and ionization parameter from the measured diagnostic ratios. We also compare black hole masses obtained from this method with values derived from widely-applied correlations between mass, line broadening and luminosity. Good agreement is found for both radius and black hole mass comparisons.  相似文献   

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