Icy moon oceans are promising targets in the search for extraterrestrial life, but characterizing their internal dynamics remains challenging, as most oceanic processes are obscured from direct observation by the overlying ice shell. In contrast, the ice shell itself is relatively accessible to observation and may serve as a window into the ocean below. As the only liquid layer in the system, t...
Host: Di L
Thirty years after the discovery of an exoplanet orbiting a Sun-like star, we have confirmed over 6,000 exoplanets. However, the existence of a Solar System analog – let alone an exo-Earth – remains elusive. This gap in our knowledge reflects not the uniqueness of our home, but the technical challenge of directly detecting habitable worlds around Sun-like stars. High-contrast imaging, enabled...
本报告将介绍国际暗能量研究的最新进展,介绍暗能量理论模型,特别是描述状态方程越过 宇宙学常数线的Quintom 理论的发展历史和研究现状; 介绍我国阿里原初引力波探测实验(AliCPT)的现状和下一步规划及预期科学目标; 介绍AliCPT 探测暗能量动力学机制的可能性。报告人简介张新民 研究员,阿里原初引力波探测实验首席科学家/AliCPT国际合作组发言人。1991年美国洛杉矶加州大学(UCLA)研究生毕业获博士学位,1996年回国在高能...
The detection of the first hot Jupiter around a main sequence star 30 years ago has opened the question about the origin of these planets. Considering that these planets accrete their gaseous envelope in the protoplanetary disc they are born in, it makes sense to relate the formation location of these planets to the chemical composition of the disc. In particular, the idea to related the atmosp...
The discovery of the "little red dots" (LRDs) with the James Webb Space Telescope has revealed a host of surprises about this mysterious class of high-redshift objects. Their physical nature remains hotly contested. I will argue that LRDs trace the initial phase of supermassive black holes that predates the formation of their host galaxies. As such, they offer a uniquely valuable laboratory to ...
M87, the nearest radio galaxy hosting a supermassive black hole of six billion solar masses, offers a unique laboratory for probing black hole accretion and jet-launching mechanisms. Over the past two decades, high-resolution observations at multiple spatial scales have revealed striking structural variations in its jet and accretion system. By linking these variations across microarcsecond to ...
Quasi-periodic eruptions (QPEs) are intense repeating soft X-ray bursts with recurrence times about a few hours to a few weeks from galactic nuclei. More and more observations show that QPEs are associated with tidal disruption events (TDEs), especially TDEs in recently faded active galactic nucleis (AGNs). The intriguing timing pattern of QPEs indicates that (at least a fraction of) QPEs are t...
During the 14 billion year journey from the last scattering surface to the Earth, cosmic microwave background (CMB) photons were deflected (CMB lensing), stretched (the ISW effect) and scattered (the Sunyaev Zel’dovich effect and patchy screening). The induced secondary CMB anisotropies contain invaluable information on missing baryons, dark matter, dark energy, gravity, and the origin mechani...
Observations over the past decade have revealed that galaxies lose many of the metals they produce to the circumgalactic medium, and that the metals they retain are arranged in complex patterns that go beyond simple radial gradients. Theoretical models for how metals move through and out of the interstellar medium to produce these distributions are still in their infancy. In this talk, I discus...