本学期学术活动

Jun Zhang:Recent Progress in Weak Lensing Measurement

2016-11-24    点击:

报告题目:Recent Progress in Weak Lensing Measurement

报 告 人:Jun Zhang (上海交通大学)

报告时间:2016年11月24日下午2:00

报告地点:蒙民伟科技南楼S727

报告摘要:Weak lensing is an important probe of the cosmic structure and the scale evolution of our Universe. We show that the weak lensing effect (also called cosmic shear) can be measured accurately from background galaxy images through Fourier transformation in the presence of background noise, source Poisson noise, and finite pixel size, without assumptions on the morphologies of galaxy and PSF. More recently, we have further optimized the way of taking the ensemble average of the cosmic shear signal, and the way of measuring the point-spread-function at the positions of the galaxies. We show some preliminary measurement results using the CFHTlens data, and demonstrate that our method is the most promising technique for cosmic shear measurement in the ongoing and upcoming large scale galaxy surveys.