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排序方式: 共有343条查询结果,搜索用时 31 毫秒
1.
Milan M. Ćirković 《Astrophysics and Space Science》2003,283(2):273-277
The existence of rotation signatures in damped Lyαabsorption systems represents a crucial test of the hypothesis that these features arise in disks of normal spiral galaxies. We apply the method for evaluating such signatures to the metal absorption lines in QSO 0528-250. In particular, the systemic redshift of the absorber is inferred from the recent detection of emission in the absorber by Möller and Warren. The kinematics of this absorber are particularly interesting because molecular hydrogen, the densest ISM component of the assumed foreground absorbing galaxy, is detected. Contrary to a recent claim, the method yields a satisfactory value for the assumed rotation velocity of the absorber. 相似文献
2.
Viviane Pierrard Milan Maksimovic Joseph Lemaire 《Astrophysics and Space Science》2001,277(1-2):195-200
Electron velocity distribution functions (VDF) observed in the low speed solar wind flow are generally characterized by ‘core’
and ‘halo’ electrons. In the high speed solar wind, a third population of ‘strahl’ electrons is generally observed. New collisional
models based on the solution of the Fokker-Planck equation can be used to determine the importance of the different electron
populations as a function of the radial distance. Typical electron velocity distribution functions observed at 1 AU from the
Sun are used as boundary conditions for the high speed solar wind and for the low speed solar wind. Taking into account the
effects of external forces and Coulomb collisions with a background plasma, suprathermal tails are found to be present in
the electron VDF at low altitudes in the corona when they exist at large radial distances.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
3.
Milan Burša 《Earth, Moon, and Planets》1992,56(1):57-60
The tidal long-term decrease in the angular velocity of the Earth's rotation has been estimated on the basis of the angular momentum tidal balance in the Earth-Moon-Sun system. The observed (LLR) tidal long-term decrease in the Moon's mean motion, the apparent secular acceleration in the mean longitude of the Sun and the long-term decrease in the 2nd degree zonal geopotential parameter were used.Presented at the XXth General Assembly of the I.A.G., Vienna, August 15, 1991. 相似文献
4.
Milan Burša 《Studia Geophysica et Geodaetica》1991,35(3):145-150
Summary The estimate of the tidal long-term decrease in the angular velocity of the Earth's rotation due to the Sun is given as –(0.8±0.3)×10
–22
rad s
–2. It was computed on the basis of the observed total long-term decrease in , of the observed tidal deceleration of the Moon and the observed decrease in the second-degree zonal Stokes geopotential harmonic term. Adopting the estimate given, the product of the Love number and the tidal phase lag angle due to the Sun (in degrees) comes out as 0.53±0.20.
am a z nuuu u z mu au u, az : –(0,8±0,3) 10 –22 a¶rt; –2 . ¶rt; ua n a¶rt;a u , n a¶rt;a nuu u ¶rt;z ¶rt;uu u n a¶rt;a u mz az znmuaz naama ma. u num n au, m nu¶rt;u ua a a z u ( za¶rt;a) a z nuua a (0,53±0,20).相似文献
5.
Milan Burša 《Studia Geophysica et Geodaetica》1992,36(2):109-114
Summary The principal moments of the Earth's inertia and their differences have been computed and their actual accuracy estimated on the basis of the most recent values of the 2nd degree geopotential parameters (model GEM-T2) and of the parameter H in the precession constant. The contributions due to the zero frequency zonal term in the tidal potential have been determined.
au m nmnmuaa 2- mnu (¶rt; GEM-T2) u naama nm nuu n¶rt; aua m uuu u u u amu u ¶rt;am u a mmu. u a¶rt; n¶rt; uu nm amu a a nuu nmuaa.相似文献
6.
The interrelations of the latitudinal distribution of the coronal green emission maxima, maximal numbers and areas of prominences, magnetic fields, sunspots, and polar faculae in the 20th and 21st sunspot cycles have been investigated. It is again demonstrated how the behaviour of all studied data depends on their heliographic latitude. In the polar zone, well separated from the equatorial we observe following polarity magnetic fields transported only polewards, while the equatorial zone is occupied mostly by leading polarity fields, developed there, moving equatorwards, and crossing the equator to the other hemisphere with the new cycle during the minimum of sunspot activity.This magnetic field distribution is well emphasized by the places of maximal occurrence of prominences and by the distribution of coronal green emission maxima which also differ in dependence on latitude.The question of identifying the first and last evolutionary stages of an extended cycle of activity is discussed and the existence of a magnetic activity cycle lasting 15–17 years is suggested. 相似文献
7.
A methodology for improving geopotential models has been developed. Theoretical relations have been derived converting coefficients in harmonic expansions for radial distortions due to geopotential models into geopotential Stokes coefficients. Terms of the order of 10
–10
in magnitude have been retained. 相似文献
8.
9.
10.
Milan Hvoždara Ladislav Brimich Reviewer L. Skalský 《Studia Geophysica et Geodaetica》1988,32(2):129-135
Summary The thermo-elastic deformations due to the annual temperature variation are computed. The time variation of these deformations is compared with the variation of the slow deformations observed at the tidal station in Vyhne.
Dedicated to RNDr Jan Pícha, CSc on his 70th birthday 相似文献
u mnu ¶rt;auu, a¶rt; auau mnam nmu a nnmama. ¶rt; mu ¶rt;au a ¶rt; ¶rt; ¶rt;au, u a nuu mauu ().
Dedicated to RNDr Jan Pícha, CSc on his 70th birthday 相似文献