搜索结果: 1-15 共查到“天文学 growth”相关记录19条 . 查询时间(0.187 秒)
N-Body simulations of growth from 1 km planetesimals at 0.4 AU
Origin, Solar system Planetesimals Planetary formation Earth
2015/12/25
We present N-body simulations of planetary accretion beginning with 1 km radius planetesimals in orbit about a 1 M star at 0.4 AU. The initial disk of planetesimals contains too many bodies for any c...
We use hydrodynamic simulations to examine how the baryonic components of galaxies are assembled, focusing on the relative importance of mergers and smooth accretion in the formation of ~L* systems. I...
We consider the sensitivity of the circular-orbit adiabatic contraction approximation to the baryon condensation rate and the orbital structure of dark matter haloes in the Λ cold dark matter (ΛCDM) p...
The growth of central and satellite galaxies in cosmological smoothed particle hydrodynamics simulations
theory formation
2014/12/23
We examine the accretion and merger histories of central and satellite galaxies in a smoothed particle hydrodynamics (SPH) cosmological simulation that resolves galaxies down to 7 × 109 M⊙. Most frien...
Growth of galaxies in SPH simulations
Explore Galaxy formation. Smooth particle hydrodynamics The universe simulation Galactic gas Temperature history Galaxy star
2014/12/9
We explore the growth of galaxies formed in self-consistent Smoothed Particle Hydrodynamic (SPH) cosmological simulations. In the first Chapter, we examine the temperature history of gas accreted by f...
Modelling supermassive black hole growth: towards an improved sub-grid prescription
Modelling supermassive black hole growth sub-grid prescription
2012/2/24
Accretion onto supermassive black holes (SMBHs) in galaxy formation simulations is frequently modelled by the Bondi-Hoyle formalism. Here we examine the validity of this approach analytically and nume...
The WiggleZ Dark Energy Survey: constraining the evolution of Newton's constant using the growth rate of structure
constraining evolution constant using growth rate structure
2011/10/11
We constrain the evolution of Newton's constant using the growth rate of large-scale structure measured by the WiggleZ Dark Energy Survey in the redshift range $0.1 < z < 0.9$. We use this data in two...
The outcome of protoplanetary dust growth: pebbles, boulders, or planetesimals? III. Sedimentation driven coagulation inside the snow-line
Methods Numerical Planets satellites formation Protoplanetary disks
2011/10/20
We investigate dust growth due to settling in a 1D vertical column of a protoplanetary disk. It is known from the observed 10 micron feature in disk SEDs, that small micron-sized grains are present at...
Dust grain growth in the interstellar medium of galaxies at redshifts 4
Dust grain growth interstellar medium galaxies redshifts
2011/10/21
To discriminate between different dust formation processes is a key issue in order to understand its properties. We analysed six submillimeter galaxies at redshifts 4
Black Hole growth and AGN obscuration by instability-driven inflows in high-redshift disk galaxies fed by cold streams
instability-driven inflows high-redshift disk galaxies cold streams
2011/9/29
Disk galaxies at high redshift have been predicted to maintain high gas surface densities due to continuous feeding by intense cold streams leading to violent gravitational instability, transient feat...
The impact of realistic models of mass segregation on the event rate of extreme-mass ratio inspirals and cusp re-growth
realistic models mass segregation the event rate
2011/1/11
One of the most interesting sources of gravitational waves (GWs) for LISA is the inspiral of compact objects on to a massive black hole (MBH), commonly referred to as an "extreme-mass ratio inspiral" ...
Runaway Growth During Planet Formation: Explaining the Size Distribution of Large Kuiper Belt Objects
circumstellar matter Kuiper belt planetary systems general planets and satellites
2010/11/9
Runway growth is an important stage in planet formation during which large protoplanets form,
while most of the initial mass remains in small planetesimals. The amount of mass converted into large pr...
A Compact Early-type Galaxy at z = 0.6 Under a Magnifying Lens: Evidence For Inside-out Growth
galaxies elliptical and lenticular cD
2010/11/10
We use Keck laser guide star adaptive optics imaging and exploit the magnifying effects of strong gravitational lensing (the effective resolution is FWHM 200 pc) to investigate the sub-kpc scale of ...
Testing gravity using the growth of large scale structure in the Universe
Methods numerical — Cosmology theory — dark energy
2010/11/15
Future galaxy surveys hope to distinguish between the dark energy and modified gravity
scenarios for the accelerating expansion of the Universe using the distortion of clustering in
redshift space. ...
A Method for Judging Decay or Growth of the Magnetic Field of Pulsar
Pulsar—decay or growth of magnetic field—method of judgement
2010/9/15
This paper provides a method for judging growth or decay of the magnetic field of pulsar by using pulse period P, or frequency ν, and its first and second derivatives P˙, P¨ or ν˙, ν¨. The author uses...