报告摘要：Modern physics and astronomy both originated from Galileo. Hertz invented the first antenna and demonstrated the wave-particle duality of light. These developments give rise to radio astronomy and giant dishes. The Parkes multi-beam system transformed single-dish radio astronomy, delivering the largest haul of new pulsars, definitive HI galaxy catalogues, and the standard HI maps of the Southern sky. These landmark surveys had to be conducted separately, due to the conflicting observation requirements. We invented the high-cadence CAL technique, in which the calibration signal is injected at the sampling rate and facilitate, for the first time, truly commensal pulsar and spectral-line surveys. Implemented on FAST with drift-scan mode, the Commensal Radio Astronomy FAST Survey (CRAFTS) has discovered more than 230 pulsars and 10 FRBs, and released over 5,000 square degrees of calibrated HI images. I will report a few science highlights from CRAFTS, in the context of surveying the radio sky. CRAFTS' high cadence sampling of the radio sky also give rise to the concept of the "time frontier". I coined this term to represent the quantum foundation of the Universe that is to be revealed by exploring extreme transients. Hypothetical considerations will be given to possible lines of investigations.
主讲人简介：Dr. Li, radio astronomer, is a Chair Professor of Tsinghua University and the former Chief Scientist of FAST. He pioneered several observing and data analysis techniques, including HI Narrow Self-Absorption (HINSA) and high-cadence CAL. These techniques led to major discoveries and new surveys. including the Commensal Radio Astronomy FasT Survey (CRAFTS), precise measurement of interstellar magnetic field, and the first persistently active fast radio bursts (FRB). He has published more than 400 peer-reviewed journal articles including 8 on Nature or Science, with more than 14000 citations. He won the 2022 Distinguished Achievement Award of the Chinese Academy of Sciences (CAS); the 3rd National Innovation Award from the Chinese government; and the 17th Marcel Grossmann Award for ”numerous innovations in characterizing the dynamic universe”.
