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相关论文: SHELS: The Hectospec Lensing Survey

200 篇论文

We present our cosmic shear analysis of GEMS, one of the largest wide-field surveys ever undertaken by the Hubble Space Telescope. Imaged with the Advanced Camera for Surveys (ACS), GEMS spans 795 square arcmin in the Chandra Deep Field…

We describe the hCOSMOS redshift survey of the COSMOS field conducted with the Hectospec spectrograph on the MMT. In the central 1~deg$^2$, the hCOS20.6 subset of the survey is $>90\%$ complete to a limiting $r=20.6$. The hCOSMOS survey…

星系天体物理 · 物理学 2018-02-07 Ivana Damjanov , H. Jabran Zahid , Margaret J. Geller , Daniel G. Fabricant , Ho Seong Hwang

The power spectrum of weak lensing shear caused by large-scale structure is an emerging tool for precision cosmology, in particular for measuring the effects of dark energy on the growth of structure at low redshift. One potential source of…

天体物理学 · 物理学 2009-11-13 Rachel Mandelbaum , Christopher M. Hirata , Mustapha Ishak , Uros Seljak , Jonathan Brinkmann

We present the definitive data for the full sample of 131 strong gravitational lens candidates observed with the Advanced Camera for Surveys (ACS) aboard the Hubble Space Telescope by the Sloan Lens ACS (SLACS) Survey. All targets were…

Strong gravitational lensing is a powerful tool for investigating dark matter and dark energy properties. With the advent of large-scale sky surveys, we can discover strong lensing systems on an unprecedented scale, which requires efficient…

The statistical power of weak lensing measurements is principally driven by the number of high redshift galaxies whose shapes are resolved. Conventional wisdom and physical intuition suggest this is optimised by deep imaging at long (red or…

The Shear TEsting Programme (STEP) is a collaborative project to improve the accuracy and reliability of weak lensing measurement, in preparation for the next generation of wide-field surveys. We review sixteen current and emerging shear…

Weak gravitational lensing of background galaxies offers an excellent opportunity to study the intervening distribution of matter. While much attention to date has focused on the two-point function of the cosmic shear, the three-point…

天体物理学 · 物理学 2008-11-26 Scott Dodelson , Pengjie Zhang

The shear triplet statistics is a geometric method to measure cosmological parameters with observations in the weak gravitational lensing regime towards massive haloes. Here, this proposal is considered to probe the dark energy equation of…

天体物理学 · 物理学 2008-11-26 Mauro Sereno

Weak gravitational lensing surveys are rapidly becoming important tools to probe directly the mass density fluctuations in the universe and its background dynamics. Earlier studies have shown that it is possible to model the statistics of…

天体物理学 · 物理学 2009-11-07 Patrick Valageas , Andrew J. Barber , Dipak Munshi

Weak gravitational lensing has become an important tool to study the properties of dark matter halos around galaxies, thanks to the advent of large panoramic cameras on 4m class telescopes. This area of research has been developing rapidly…

天体物理学 · 物理学 2009-11-11 Henk Hoekstra

Label hierarchy is an important source of external knowledge that can enhance classification performance. However, most existing methods rely on predefined label hierarchies that may not match the data distribution. To address this issue,…

机器学习 · 计算机科学 2023-04-27 Zhiquan Tan , Zihao Wang , Yifan Zhang

We investigate the possibility of applying machine learning techniques to images of strongly lensed galaxies to detect a low mass cut-off in the spectrum of dark matter sub-halos within the lens system. We generate lensed images of systems…

宇宙学与河外天体物理 · 物理学 2020-05-13 Sreedevi Varma , Malcolm Fairbairn , Julio Figueroa

We have analysed ~24 square degrees of R_C-band imaging data from the Red-Sequence Cluster Survey (RCS), and measured the excess correlations between galaxy ellipticities on scales ranging from 1 to 30 arcminutes. We have used data from two…

We present the first results of a MOS campaign to follow up cluster candidates located via weak lensing. Our main goals are to search for spatial concentrations of galaxies that are plausible optical counterparts of the weak lensing…

In this contribution we review the large body of work carried out over the past two decades to probe the dark matter in the local universe using redshift survey and peculiar velocity data. While redshift surveys have evolved rapidly over…

天体物理学 · 物理学 2007-05-23 L. da Costa

In this paper we introduce the SEAGLE (i.e. Simulating EAGLE LEnses) program, that approaches the study of galaxy formation through strong gravitational lensing, using a suite of high-resolution hydrodynamic simulations, Evolution and…

We present simple formulae for calculating the skewness and kurtosis of the aperture mass statistic for weak lensing surveys which is insensitive to masking effects of survey geometry or variable survey depth. The calculation is the higher…

天体物理学 · 物理学 2009-11-10 M. Jarvis , G. Bernstein , B. Jain

We use numerical simulations of ray tracing through N-body simulations to investigate weak lensing by large-scale structure. These are needed for testing the analytic predictions of two-point correlators, to set error estimates on them and…

天体物理学 · 物理学 2007-05-23 Bhuvnesh Jain , Uros Seljak , Simon White