Search Publications
On the Determination of Stellar Mass and Binary Fraction of Open Clusters within 500 pc from the Sun
Chen, Li; Zhong, Jing; Hou, Jinliang +3 more
We investigated the stellar mass function and the binary fraction of 114 nearby open clusters (OCs) using the high-precision photometric data from Gaia Data Release 3 (Gaia DR3). We estimated the mass of member stars by using a ridge line that is better in line with the observed color–magnitude diagram, thus obtaining more accurate stellar mass an…
Simulated Coronal Mass Ejections on a Young Solar-type Star and the Associated Instantaneous Angular Momentum Loss
Tian, Hui; Alvarado-Gómez, Julián D.; Poppenhäger, Katja +3 more
Coronal mass ejections (CMEs) on stars can change the stars' magnetic field configurations and mass-loss rates during the eruption and propagation and therefore, may affect the stars' rotation properties on long timescales. The dynamics of stellar CMEs and their influence on the stellar angular momentum loss rate are not yet well understood. In or…
Unveiling the Small-scale Jets in the Rapidly Growing Supermassive Black Hole IZw1
Ho, Luis C.; Gallo, Luigi C.; Yao, Su +10 more
Accretion of black holes at near-Eddington or super-Eddington rates represents the most powerful episode driving black hole growth, potentially occurring across various types of objects. However, the physics governing accretion and jet–disk coupling in such states remains unclear, primarily due to the difficulty in detecting associated jets, which…
Structure and Color Gradients of Ultradiffuse Galaxies in Distant Massive Galaxy Clusters
Cui, Qifan; Yesuf, Hassen M.; Wu, Hong +2 more
We have measured structural parameters and radial color profiles of 108 ultradiffuse galaxies (UDGs), carefully selected from six distant massive galaxy clusters in the Hubble Frontier Fields (HFF) in a redshift range from 0.308 to 0.545. Our best-fitting GALFIT models show that the HFF UDGs have a median Sérsic index of 1.09, which is close to 0.…
On the Roles of Stellar Rotation and Binarity in NGC 2423's Main-sequence Turnoff Region
Wang, Li; Li, Chengyuan; Bu, Yutian +2 more
Research has shown that many young and intermediate-age clusters (younger than ∼2 Gyr) have extended main sequences and extended main-sequence turnoffs (eMSTOs), which cannot be adequately described by a single isochrone. The reason for the extended main sequences is now known, with the most probable cause being the fast rotation of stars. However…
LoVoCCS. II. Weak Lensing Mass Distributions, Red-sequence Galaxy Distributions, and Their Alignment with the Brightest Cluster Galaxy in 58 Nearby X-Ray-luminous Galaxy Clusters
Cooper, M. C.; Donahue, Megan; Miyatake, Hironao +31 more
The Local Volume Complete Cluster Survey is an ongoing program to observe nearly a hundred low-redshift X-ray-luminous galaxy clusters (redshifts 0.03 < z < 0.12 and X-ray luminosities in the 0.1–2.4 keV band L X500c > 1044 erg s‑1) with the Dark Energy Camera, capturing data in the u, g, r, i, z bands wit…
Mass Assembly in Massive Star Formation: A Fragmentation Study of ATLASGAL Clumps
Wyrowski, Friedrich; Menten, Karl M.; Williams, Jonathan P. +3 more
The mass assembly in star-forming regions arises from the hierarchical structure in molecular clouds in tandem with fragmentation at different scales. In this paper, we present a study of the fragmentation of massive clumps covering a range of evolutionary states, selected from the ATLASGAL survey, using the compact configuration of the Submillime…
Asteroseismology of the Nearby K Dwarf σ Draconis Using the Keck Planet Finder and TESS
Knutson, Heather; Li, Yaguang; Lee, Chien-Hsiu +76 more
Asteroseismology of dwarf stars cooler than the Sun is very challenging owing to the low amplitudes and rapid timescales of oscillations. Here we present the asteroseismic detection of solar-like oscillations at 4-minute timescales (
The Metallicities of Five Small High-velocity Clouds
Richter, Philipp; Lockman, Felix J.; Fox, Andrew J. +5 more
High-velocity clouds (HVCs) are multiphase gas structures whose velocities (∣v LSR∣ ≥ 100 km s-1) are too high to be explained by Galactic disk rotation. While large HVCs are well characterized, compact and small HVCs (with H I angular sizes of a few degrees) are poorly understood. Possible origins for such small clouds inclu…
Axial Flux Evolution of Small-scale Magnetic Flux Ropes from 0.06 to 10 au
Wang, Haimin; Kim, Hyomin; Lee, Jeongwoo +2 more
Small-scale magnetic flux ropes (SMFRs) fill much of the solar wind, but their origin and evolution are debated. We apply our recently developed, improved Grad–Shafranov algorithm for the detection and reconstruction of SMFRs to data from Parker Solar Probe, Solar Orbiter, Wind, and Voyager 1 and 2 to detect events from 0.06 to 10 au. We observe t…