The abstract of Dr.Wentao Luo's talk is as follows:
Weak lensing analysis becomes a popular method in measuring the distribution of dark matter due to the fact that it is model independent. And large imaging surveys as SDSS, CFHT, SUBARU and HST equipped with Charge-Coupled Detector enable weak lensing study to move from theory to real observation. However, it suffers many systematics despite of its advantages, one of which is from Point Spread Function. The isotropy and anisotropy effect of PSF introduce multiplicative and additive error to weak lensing analysis, which have to be removed properly. In this talk, we present our own method of the removal of PSF systematics, and further we present the testing results based on various simulations e.g., GREAT3, Mapping the Dark Matter, SHERA e.t.c. Further, we processed all the imaging data of SDSS DR7 and compared our results to Rachel Mandelbaum's results the consistency between the two indicates that our results are ready to go further for scientific research. In future, other than scientific study of galaxy-galaxy lensing from SDSS Dr7. We will continue to explore the possibilities to push the accuracy to meet the requirement of LSST, meaning to control the systematics under <1% level.