Galaxy merging, the fundamental plane of elliptical galaxies and the  M_BH−σ₀  relation     

C. Nipoti  P. Londrillo  L. Ciotti 《Monthly notices of the Royal Astronomical Society》2003,342(2):501-512

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Dynamical response to supernova-induced gas removal in two-component spherical galaxies     

Masahiro Nagashima &#;  Yuzuru Yoshii 《Monthly notices of the Royal Astronomical Society》2003,340(2):509-518

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The growth and structure of dark matter haloes     

D. H. Zhao  H. J. Mo  Y. P. Jing  G. Börner 《Monthly notices of the Royal Astronomical Society》2003,339(1):12-24

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Three-dimensional calculations of high- and low-mass planets embedded in protoplanetary discs     

M. R. Bate  S. H. Lubow  G. I. Ogilvie  K. A. Miller 《Monthly notices of the Royal Astronomical Society》2003,341(1):213-229

We analyse the non-linear, three-dimensional response of a gaseous, viscous protoplanetary disc to the presence of a planet of mass ranging from 1 Earth mass (1 M_⊕) to 1 Jupiter mass (1 M_J) by using the zeus hydrodynamics code. We determine the gas flow pattern, and the accretion and migration rates of the planet. The planet is assumed to be in a fixed circular orbit about the central star. It is also assumed to be able to accrete gas without expansion on the scale of its Roche radius. Only planets with masses   M _p≳ 0.1 M_J  produce significant perturbations in the surface density of the disc. The flow within the Roche lobe of the planet is fully three-dimensional. Gas streams generally enter the Roche lobe close to the disc mid-plane, but produce much weaker shocks than the streams in two-dimensional models. The streams supply material to a circumplanetary disc that rotates in the same sense as the orbit of the planet. Much of the mass supply to the circumplanetary disc comes from non-coplanar flow. The accretion rate peaks with a planet mass of approximately 0.1 M_J and is highly efficient, occurring at the local viscous rate. The migration time-scales for planets of mass less than 0.1 M_J, based on torques from disc material outside the Roche lobes of the planets, are in excellent agreement with the linear theory of type I (non-gap) migration for three-dimensional discs. The transition from type I to type II (gap) migration is smooth, with changes in migration times of about a factor of 2. Starting with a core which can undergo runaway growth, a planet can gain up to a few M_J with little migration. Planets with final masses of the order of 10 M_J would undergo large migration, which makes formation and survival difficult.  相似文献   

Are there brown dwarfs in globular clusters?     

I. A. Bonnell  C. J. Clarke  M. R. Bate  M. J. McCaughrean  J. E. Pringle  H. Zinnecker 《Monthly notices of the Royal Astronomical Society》2003,343(3):L53-L57

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Clumpiness in Star Forming Regions     

S. Viti 《Astrophysics and Space Science》2003,285(3-4):791-800

In this article, some aspects of the clumpy nature of molecular clouds are reviewed. In particular the observational evidence for small-scale structures both in low and high mass star forming regions will be discussed. I will review some examples of `clumpiness' such as: i) the molecular clumps ahead of HH objects and how the study of the physical and chemical nature of these clumps is important for the understanding of the clumpiness of the Interstellar Medium; and ii)hot cores and their use as a tool to study the early phases of massive star formation. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

Stellar population synthesis at the resolution of 2003   总被引：2，自引：0，他引：2  

G. Bruzual  S. Charlot 《Monthly notices of the Royal Astronomical Society》2003,344(4):1000-1028

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基于统一强度理论的地基临界荷载公式   总被引：1，自引：0，他引：1  

范文  林永亮  秦玉虎 《地球科学与环境学报》2003,25(3):48-51

基于统一强度理论,按照临界荷载公式的推导方法,得到地基临界荷载的统一解公式。Mohr-Coulomb强度理论计算的结果为其特例。把计算结果与《建筑地基基础设计规范》中的结果进行了对比分析,认为当不同程度地考虑中间主应力σ2的影响时,可以有效地发挥地基的强度潜能。并通过实例计算了统一强度理论参数b取不同值时地基承载力特征值,并进行了对比分析。  相似文献   

Core dissolution and the dynamics of massive stars in young stellar clusters     

S. G. Vine  I. A. Bonnell 《Monthly notices of the Royal Astronomical Society》2003,342(1):314-320

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A Solution of Einstein's Field Equations fora Tachyonic Gas: Possible Astrophysical Applications     

W.J. Cocke  K.H. Green 《Astrophysics and Space Science》2003,288(4):327-346

In this paper we show that a change in the signs of some of the metric components of the solution of the field equations for the classical cosmic string results in a solution which we interpret as a time-dependent wall composed of tachyons. We show that the walls have the property of focusing the paths of particles which pass through them. As an illustration of this focusing, we demonstrate the results of a simple simulation of the interaction between one such tachyon wall and a rotating disk of point masses. This interaction leads to the temporary formation of spiral structures. These spiral structures exist for a time on the order of one galactic rotation. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献