Title: KiDS-1000: Cosmology with improved cosmic shear measurements
Speaker: Shunsheng Li （李顺生）
Time: 2:00 pm August 23rd (Wednesday)
Location: Yinhe Lecture Hall, 19th floor （19楼银河报告厅）
Tencent Meeting：651-832-8129
Abstract: Weak gravitational lensing by large-scale structure, also known as cosmic shear, plays a crucial role in modern cosmology, powerfully probing the Universe's matter distribution. Interestingly, recent cosmic shear results from the KiDS, DES, and HSC surveys show an intriguing discrepancy with Planck's CMB observations concerning the amplitude of matter fluctuations. In this talk, I will discuss recent advancements made to mitigate weak lensing systematics in the KiDS survey, with a particular focus on the shear measurement process. Our recent work introduced several key improvements to cosmic shear measurements for KiDS, including enhanced galaxy shape measurements and the introduction of a new suite of multi-band image simulations. We incorporated these advancements into the latest KiDS cosmic shear analysis, leading to updated cosmological parameter constraints.
Bio: Shunsheng Li is currently a PhD candidate at Leiden Observatory in the Netherlands. Prior to this, he earned an MSc in Astrophysics from the University of Chinese Academy of Sciences in 2019, and a BSc in Astronomy from Nanjing University in 2016. His research interests span the spectrum of gravitational lensing effects, encompassing microlensing, strong lensing, and weak lensing. His current research focuses primarily on weak lensing measurements and their applications in the study of dark matter properties and the refinement of cosmological models.
