Title: Colour gradient bias in weak lensing observation

Speaker：Doctor Xinzhong Er
Institute: INAF-Observatory of Rome
Time：2017.03.14（Tuesday） 10:10
Place：Physics Building 407, Haiyun Campus, Xiamen University
Abstract：Weak gravitational lensing is one of the powerful tool in cosmology. It can probe the dark matter distribution without assuming the nature or dynamic status of the matter, from small scale, galaxy halo, galaxy cluster to large scale structures of the universe.  One of the most important issue in weak lensing is how to correct the PSF of the lensed image.  The wide band receiver in space telescope can take the advantages of small space PSF. With the increasing accuracy, we are facing another problem: the spatial variations of SED. I will talk about this problem and how we going to calibration it for the future weak lensing survey.