搜索结果: 1-15 共查到“天体物理学 Density”相关记录24条 . 查询时间(0.09 秒)
Magnetic Energy Storage and Current Density Distributions for Different Force-Free Models
Magnetic fi elds Corona - Active Regions Structure - Electric Cur- rents Current Sheets
2011/10/10
The change in the magnetic configuration due to the increase/decrease of electric current for different force-free models (potential, linear and nonlinear force-free fields) has never been studied in ...
The role of the initial surface density profiles of the disc on giant planet formation: comparing with observations
the initial surface density profiles the disc on giant planet formation
2011/1/10
In order to explain the main characteristics of the observed population of extrasolar planets and the giant planets in the Solar System, we need to get a clear understanding of which are the initial c...
Structure in phase space associated with spiral and bar density waves in an N-body galactic disk
bar density waves N-body galactic disk
2011/1/11
An N-body simulation of a Galactic disk is used to study the stellar phase space distribution or velocity distributions in different local neighborhoods. Pattern speeds identified in Fourier spectrogr...
We study the mass-density relationship n m^x in molecular cloud clumps, considering various relations between the gravitational, kinetic, internal and magnetic energy. Clumps are described statistical...
The H-alpha Luminosity Function and Star-Formation Rate Volume Density at z=0.8 from the NEWFIRM H-alpha Survey
galaxies photometry — galaxies emission lines — galaxies distances and redshifts — galaxies
2010/11/15
We present new measurements of the H luminosity function (LF) and star-formation rate (SFR)
volume density for galaxies at z ∼ 0.8. Our analysis is based on 1.18μm narrowband data from
the NE...
Warm dark matter at small scales: peculiar velocities and phase space density
Warm dark matter small scales peculiar velocities phase space density
2010/11/12
We study the scale and redshift dependence of the power spectra for density perturbations and
peculiar velocities, and the evolution of a coarse grained phase space density for (WDM) particles that d...
Primordial non-Gaussianity in the Bispectrum of the Halo Density Field
Inflation Large Scale Structure Primordial non-Gaussianity
2010/11/11
The bispectrum vanishes for linear Gaussian elds and is thus a sensitive probe of non-
linearities and non-Gaussianities in the cosmic density eld. Hence, a detection of the bispectrum in the halo ...
Accretion Discs with an Inner Spiral Density Wave
accretion accretion discs - binaries general - binaries close - stars dwarf novae - novae
2010/11/16
In Montgomery (2009a), we show that accretion discs in binary systems could retrogradely precess by the same physics that causes the Earth to retrogradely precess [i.e., tidal torques by the Moon and ...
Constraints on the Cosmic-Ray Density Gradient beyond the Solar Circle from Fermi gamma-ray Observations of the Third Galactic Quadrant
cosmic rays – gamma rays ISM – ISM general
2010/11/10
We report an analysis of the interstellar-ray emission in the third Galactic quadrant measured
by the Fermi Large Area Telescope. The window encompassing the Galactic plane from longitude 210◦ ...
Galaxy clustering and projected density profiles as traced by satellites in photometric surveys: Methodology and luminosity dependence
Galaxy clustering projected density profiles photometric surveys
2010/11/12
We develop a new method which measures the projected density distribution wp(rp)n of photometric galaxies surrounding a set of spectroscopically-identified galaxies, and simultaneously the projected c...
Modeling CO Emission: I. CO as a Column Density Tracer and the X-Factor in Molecular Clouds
Modeling CO Emission X-Factor Molecular Clouds
2010/11/12
Theoretical and observational investigations have indicated that the abundance of car-bon monoxide (CO) is very sensitive to intrinsic properties of the gaseous medium,
such as density, metallicity, ...
Effects of Initial Condition and Cloud Density on the Composition of the Grain Mantle
Molecular clouds ISM abundances molecules chemical evo-lution Monte-Carlo simulations
2010/11/15
Evolution of grain mantles in various interstellar environment is studied. We concentrate mainly on water, methanol, carbon di-oxide, which constitute nearly 90% of the grain mantle. We investigate ho...
The X-ray Power Spectral Density Function of the Seyfert Active Galactic Nucleus NGC 7469
High Energy Astrophysical Phenomena (astro-ph.HE)
2011/1/5
We present the broadband X-ray power spectral density function (PSD) of the X-ray-luminous Seyfert 1.2 NGC 7469, measured from Rossi X-ray Timing Explorer monitoring data and two XMM-Newton observatio...
HAT-P-26b: A Low-Density Neptune-Mass Planet Transiting a K Star
Earth and Planetary Astrophysics (astro-ph.EP)
2010/12/24
We report the discovery of HAT-P-26b, a transiting extrasolar planet orbiting the moderately bright V=11.744 K1 dwarf star GSC 0320-01027, with a period P = 4.234516 +- 0.000015 d, transit epoch Tc = ...
Quasar variability limits on cosmological density of cosmic strings
Quasar variability limits cosmological density cosmic strings
2010/3/19
We put robust upper limits on the average cosmological density \Omega_s of cosmic strings based on the variability properties of a large homogeneous sample of SDSS quasars. We search for an excess of ...
