北京大学科维理天文与天体物理研究所

Featured Science

The Interaction between AGN and Starburst Activity as Viewed with JWST

With excellent sensitivity and spatial and spectral resolutions, the James Webb Space Telescope (JWST) presents an unprecedented opportunity to promote our understanding of the evolutionary processes of galaxies. Taking advantage of a recently available set of JWST observations taken with Medium Resolution Spectrograph (MRS) on the Mid-Infrared Instrument (MIRI), Dr. Lulu Zhang, who got his PhD degree this July from Peking University under the supervision of Prof. Luis C. Ho at the Kavli Institute for Astronomy and Astrophysics at Peking University, ascertained whether and the manner in which AGN feedback influences the circumnuclear star formation of the well-studied nearby luminous infrared galaxy, NGC 7469, which also hosts a powerful type 1 active galactic nucleus (AGN). Their findings appear in The Astrophysical Journal Letters (2023, 953, L9).

PKU Astronomers Sheds Light on Evolutionary Paths of Supermassive Black Holes and Their H...

A new paper entitled “Evolutionary Paths of Active Galactic Nuclei and Their Host Galaxies” published on 17 August 2023 in Nature Astronomy provides critical new insights on the co-evolution of supermassive black holes and their host galaxies. The research, conducted by Dr. Ming-Yang Zhuang, who graduated from Peking University in 2022 and currently affiliated with the University of Illinois Urbana-Champaign, and Prof. Luis C. Ho from the Kavli Institute for Astronomy and Astrophysics at Peking University, derived structural and photometric properties of host galaxies of nearly 11,500 redshift ≤ 0.35 unobscured active galactic nuclei (AGNs) using data from Pan-STARRS1 3PI Steradian Survey to explore the connections between black hole mass and the properties of host galaxies in the nearby Universe. Peking University is the primary affiliation of the paper.

PKUers finds Key Evidence for Existence of Nanohertz Gravitational Waves

A group of Chinese scientists has recently found key evidence for the existence of nanohertz gravitational waves, marking a new era in nanohertz gravitational wave research. The research was based on pulsar timing observations carried out with the Five-hundred-meter Aperture Spherical Telescope (FAST).The research was conducted by the Chinese Pulsar Timing Array (CPTA) collaboration. Researchers (Prof. Kejia Lee, Post-Doc. Siyuan Chen, PhD students Jiangwei Xu, and Zihan Xue) from Department of Astronomy School of physics and Kavli Institute of Astronomy and Astrophysics of Peking University played vital roles in the collaboration. Their findings were published online in the academic journal Research in Astronomy and Astrophysics (RAA).

Starlight and the First Black Holes: Researchers Probe the Relationship Between the Black...

​New images from the James Webb Space Telescope (JWST) have revealed, for the first time, starlight from two massive galaxies hosting actively growing black holes – quasars – seen less than a billion years after the Big Bang. The black holes have masses are close to a billion times that of the Sun, and the host galaxy masses are almost one hundred times larger, a ratio similar to what is found in the more recent universe. A powerful combination of the wide-field survey of the Subaru Telescope and the JWST has paved a new path to study the distant universe, reports a new study in Nature.

Astronomers image winds from the terrestrial planet forming region of a nearby disk

In an article in Nature Astronomy published on June 19, a team of international astronomers, led by Purple Mountain Observatory (PMO) and Kavli Institute of Astronomy and Astrophysics at Peking University (PKU/KIAA), reported the highest resolution images ever obtained of the wind from one of these disks. The physical scale of 3.5 AU is small enough to measure the physics in regions where terrestrial planets form. Interpreting the images with state-of-the-art simulations led to surprising results that alter our view of the physics that determines how disks evolve.

The giant binary black hole in OJ 287 is “slimmed” by the latest observations

An international research group including Professor Fukun Liu at The Department of Astronomy and The Kavli Institute for Astronomy and Astrophysics of Peking University in Beijing, China, presents important new results on the active galaxy OJ 287, based on the most dense and longest radio-to-high-energy observations to date. The scientists were able to test crucial binary model predictions using multiple observing tools, including the Effelsberg radio telescope and the Neil Gehrels Swift Observatory. The team measured an independent mass of the black hole mass and the mass in the disk that surrounds the black hole. The results show that an exceptionally massive black hole exceeding 10 billion solar masses is no longer needed. Instead, the results favor models with a smaller mass of 100 million solar masses for the primary black hole, consistent with the results obtained about twenty year ago by Fukun Liu and Xue-Bing Wu, also at Peking University. Several outstanding mysteries, including the apparent absence of the latest big outburst of OJ 287 (which has now been identified) and the much-discussed emission mechanism during the main outbursts, can be solved this way. Independent results on blazar physics that trace processes near the jet launching region were obtained. The findings are presented in two papers published in MNRAS Letters and the Astrophysical Journal.