搜索结果: 1-14 共查到“天文学 shear”相关记录14条 . 查询时间(0.096 秒)
Shear-flexion cross-talk in weak-lensing measurements
gravitational lensing, methods: data analysis, cosmology: observations
2011/10/12
Gravitational flexion, caused by derivatives of the gravitational tidal field, is potentially important for the analysis of the dark-matter distribution in gravitational lenses, such as galaxy cluster...
Gyroscopic Pumping in the Solar Near-Surface Shear Layer
Gyroscopic Pumping Solar Near-Surface
2011/9/29
We use global and local helioseismic inversions to explore the prevailing dynamical balances in the solar Near-Surface Shear Layer (NSSL). The differential rotation and meridional circulation are inti...
Elliptical Weighted HOLICs for Weak Lensing Shear Measurement part2:PSF correction and application to Abell 370
Elliptical Weighted HOLICs for Weak Lensing Shear Measurement part2:PSF correction and application to Abell 370
2011/10/20
We have developed a new method(E-HOLICs) of estimating gravitational shear by adopting an elliptical weight function to measure background galaxy images in our previous paper. Following to the previou...
On Shear-Free perturbations of FLRW Universes
On Shear-Free perturbations of FLRW Universes
2011/10/14
A surprising exact result for the Einstein Field Equations is that if pressure-free matter is moving in a shear-free way, then it must be either expansion-free or rotation-free. It has been suggested ...
Scaling and intermittency in incoherent α-shear dynamo
Dynamo – magnetic fi elds – MHD – turbulence
2011/10/8
We consider mean-field dynamo models with fluctuating \alpha effect, both with and without shear. The \alpha effect is chosen to be Gaussian white noise with zero mean and given covariance. We show an...
The Effect of Environment on Shear in Strong Gravitational Lenses
gravitational lensing strong
2010/11/15
Using new photometric and spectroscopic data in the fields of nine strong gravitational lenses that lie in galaxy groups, we analyze the effects of both the local group environment and line-of-sight g...
On the source of dense outflows from T Tauri Stars. and III. Winds driven from the star-disc shear layer
stars pre-main-sequence stars: winds outflows stars circumstellar matter – stars formation
2010/11/11
Ultraviolet observations of classical T Tauri Stars (cTTSs) have shown that there is a hot (Te ≃ 80, 000 K) and dense (ne ≃ 1010 cm−3) component associated with the large scale jet. ...
Distribution of Magnetic Shear Angle in an Emerging Flux Region
Solar and Stellar Astrophysics (astro-ph.SR)
2010/12/23
We study the distribution of magnetic shear in an emerging flux region using the high-resolution Hinode/SOT SP observations. The distribution of mean magnetic shear angle across the active region show...
Evolution of twist-shear and dip-shear in Faring active region NOAA 10930
Solar and Stellar Astrophysics (astro-ph.SR)
2010/12/23
We study the evolution of magnetic shear angle in a flare productive active region NOAA 10930. The magnetic shear angle is defined as the deviation in the orientation of the observed magnetic field ve...
Elliptical Weighted HOLICs for Weak Lensing Shear Measurement. part1:Definitions and isotropic PSF correction
Cosmology and Extragalactic Astrophysics (astro-ph.CO)
2010/12/23
We develop a new method to estimate gravitational shear by adopting an elliptical weight function to measure background galaxy images. In doing so, we introduce a new concept of "zero plane" which is ...
A bias in cosmic shear from galaxy selection: results from ray-tracing simulations
Cosmology and Extragalactic Astrophysics (astro-ph.CO)
2010/12/22
We identify and study a previously unknown systematic effect on cosmic shear measurements, caused by the selection of galaxies used for shape measurement, in particular the rejection of close (blended...
On the Shear Instability in Relativistic Neutron Stars
Relativistic Neutron Stars Shear Instability
2010/3/18
We present new results on instabilities in rapidly and differentially rotating neutron stars. We model the stars in full general relativity and describe the stellar matter adopting a cold realistic eq...
Large-scale shear and alignment of cosmic structures。
Vertical shear of the galactic interstellar medium。