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251.
本文介绍了便携式人卫光电望远镜的主要性能特点,探讨了将其应用于狮子座流星暴观测的可能性。 相似文献
252.
通常将太阳高能观测划分为三个能段,软X 射线能段(0 .1keV~10keV) ,X 射线及软γ射线能段(0 .1 MeV~10 MeV) ,γ射线能段(1 MeV 以上) 。本文就各个能段的探测技术,包括成像系统和探测器,作了全面的调研,重点在新技术的应用。 相似文献
253.
M. Magliocchetti S. J. Maddox 《Monthly notices of the Royal Astronomical Society》1999,306(4):988-993
We present a correlation function analysis for the catalogue of photometric redshifts obtained from the Hubble Deep Field image by Fernandez-Soto, Lanzetta & Yahil. By dividing the catalogue into redshift bins of width Δ z =0.4 we measured the angular correlation function w ( θ ) as a function of redshift up to z ∼4.8. From these measurements we derive the trend of the correlation length r 0 . We find that r 0 ( z ) is roughly constant with look-back time up to z ≃2, and then increases to higher values at z ≳2.4. We estimate the values of r 0 , assuming ξ ( r , z )=[ r r 0 ( z )]− γ , γ =1.8 and various geometries. For Ω0 =1 we find r 0 ( z =3)≃7.00±4.87 h −1 Mpc, in good agreement with the values obtained from analysis of the Lyman break galaxies. 相似文献
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We analyse data obtained by different ground-based video camera systems during the 1999 Leonid meteor storm. We observe similar
activity profiles at nearby observing sites, but significant differences over distances in the order of 4,000 km. The main
peak occured at 02:03 UT (λ⊙=235.286, J2000, corrected for the time of the topocentric stream encounter). At the Iberian peninsula quasi-periodic activity
fluctuations with a period of about 7 min were recorded. The camera in Jordan detected a broad plateau of activity at 01:39–01:53
UT, but no periodic variations. The Leonid brightness distribution derived from all cameras shows a lack of faint meteors
with a turning point close to +3m, which corresponds to meteoroids of approximately 10-3 g. We find a pin-point radiant at αalpha=153.65 ±0.1, δ=21.80 ±0. (λ⊙=235.290). The radiant positionis identical before and after the storm, and also during the storm no driftis observed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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A. M. Finkelstein E. A. Skurikhina I. F. Surkis A. V. Ipatov I. A. Rakhimov S. G. Smolentsev 《Astronomy Letters》2008,34(1):59-68
Regular high-precision determinations of the Earth’s orientation parameters (EOPs) on the Quasar VLBI Network were begun in
August 2006. The observations are performed within the framework of two national programs: daily sessions at three observatories
of the Network to determine all five EOPs (the RU-E program) and 8-h sessions on the Zelenchukskaya-Badary and Svetloe-Badary
baselines to determine the Universal Time (the RU-U program). The observations from August 2006 through May 2007 are analyzed.
The rms deviations of the EOP values obtained in the RU-E program from the IERS C04 series are 1.1 mas for X
p and Y
p, 37 μs for UT1-UTC, and 0.7 and 0.6 mas for X
c and Y
c, respectively. These results closely match the prospective requirements of GLONASS. The rms deviations of the Universal Times
obtained in the RU-U program from the IERS C04 series are 146 μs. We consider the immediate prospects for improving the accuracy
of EOP determinations in daily sessions and for implementing the e-VLBI mode for an online determination of the Universal
Time.
Original Russian Text ? A.M. Finkelstein, E.A. Skurikhina, I.F. Surkis, A.V. Ipatov, I.A. Rakhimov, S.G. Smolentsev, 2008,
published in Pis’ma v Astronomicheskiĭ Zhurnal, 2008, Vol. 34, No. 1, pp. 66–76. 相似文献
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