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2023.10.20

TRANSforM: stellar parameters estimated from LAMOST DR10 M dwarfs

<p>The accurate determination of stellar parameters in M-type stars holds significant importance in various astronomical studies. In our study, we employed a transfer learning method coupled with PHOENIX synthetic spectra to estimate fundamental atmospheric parameters (Teff, log g, [M/H], [α/M]) and radial velocities (RV) for an extensive dataset encompassing 581,778 M dwarfs obtained from the Lo...</p>

2023.10.17

existing tensions in ΛCDM model

<p>The concordance or standard Λ Cold Dark Matter (ΛCDM) model is a well-defined, predictive and simple cosmological model. A number of challenges of the standard ΛCDM model have been emerging during the past few years, which has been summarized by recent reviews.In this talk, I will give a brief introduction to several existing signals in cosmological and astrophysical data that appear to be i...</p>

2023.10.13

Multiband gravitatioanl wave observations of stellar binary black holes

<p>The ground-based gravitational wave (GW) observatories discover a population of merging stellar binary black holes (BBHs), which are promising targets for multiband observations by the low-, middle-, and high-frequency GW detectors. We investigate the multiband GW detections of BBHs and demonstrate the advantages of such observations in improving the localization and parameter estimates of the ...</p>

2023.10.10

Obstacles from interstellar matter and distortion for warp drive travel

<p>We investigate obstacles of superluminal “warp drive” travels from interactions with interstellar matter and from curvature effects. The effect of collision of interstellar dust particles and photons with the spacecraft will all lead to a pressure proportional to the apparent velocity of the spaceship vs. The force exerted on the spacecraft from the curvature effect has two non-trivial compon...</p>

2023.09.26

Implication of UV variability for the abundance of bright galaxies at cosmic dawn 紫外光度波动对宇宙黎明时明亮星系丰度的影响

<p>The JWST has uncovered a large population of UV-bright galaxies at redshifts above ~10, which surpasses the predictions from a range of theoretical models developed based on lower redshift galaxies. While various solutions have been proposed focusing on systematically increasing the UV photon yield in high-redshift galaxies, I will discuss in this talk an alternate solution from UV variability....</p>

2023.09.22

WALLABY detects two Polar Ring Galaxies

<p>Polar ring galaxies (PRGs) exhibit an extendedring of material oriented perpendicular to the main disk, which provide crucialclues for galaxy evolutionand dynamics, such as galaxy interaction and gas accretion. In the WALLABY Pilot Data Release 1, we found two potential polar ring galaxies: NGC 4632 and NGC 6156. We used the iDaVIE virtual reality software todecompose gas within the disk and ri...</p>

2023.09.19

Yan Liang and Ruizhe Feng

<p>Speaker: Yan LiangTitle: Lensing, Dynamics &amp; Mass Distribution of the Early-Type GalaxyAbstract:The mass structure, as one of the most important properties of early-type galaxy, is associated with the galactic formation and evolution. Nowadays, the gravitational lensing at the galaxy scale and dynamics information of the galaxy have been widely used to constrain the galaxy mass structure. In th...</p>

2023.12.21

Probing Planet Formation with the Most Extreme Cases

<p>Thousands of exoplanets have been discovered in the past ~30 years. However, there are still major gaps of knowledge in our understanding of planet formation. The most extreme exoplanets are often ideal for identifying, isolating, and investigating critical aspects of plant formation. In this talk, I will highlight three extremes of planet formation: 1) the ultra-short-period planets (&lt;1 day, &lt;...</p>

2023.12.14

Studying Particle Transport in the Magnetic Turbulence with Pulsar Wind Nebulae/Pulsar Halos with Multiwavelength Observations

<p>Pulsar wind nebulae and pulsar halos are extended sources of nonthermal radiation powered by pulsars. Morphologies of these sources reflect the spatial distribution of electrons/positrons therein, which is related to the particle transport mechanism and the turbulent nature of the background medium. Therefore, multiwavelength observations of pulsar wind nebula and pulsar halos provide a good op...</p>

2023.12.07

On the Cosmic Baryon Cycle---Insights Learned from the Cosmic Ultraviolet Baryon Survey (CUBS)

<p>The circumgalactic medium (CGM) contains the fuel for future star formation and the record of past feedback, making it uniquely sensitive to the physics of baryonic flows. Characterizing the tenuous multiphase CGM across cosmic time holds a key to unveiling the drivers of galaxy growth. The Cosmic Ultraviolet Baryon Survey (CUBS) is designed to map intergalactic and circumgalactic gas at interm...</p>