Search Publications
A new look at local ultraluminous infrared galaxies: the atlas and radiative transfer models of their complex physics
Clements, D. L.; Wang, L.; Farrah, D. +11 more
We present the ultraviolet to submillimetre spectral energy distributions (SEDs) of the HERschel Ultra Luminous Infrared Galaxy Survey (HERUS) sample of 42 local ultraluminous infrared galaxies (ULIRGs) and fit them with a Markov chain Monte Carlo code using the CYprus models for Galaxies and their NUclear Spectra (CYGNUS) radiative transfer model…
Planets Across Space and Time (PAST). III. Morphology of the Planetary Radius Valley as a Function of Stellar Age and Metallicity in the Galactic Context Revealed by the LAMOST-Gaia-Kepler Sample
Dong, Subo; Zong, Weikai; Zhu, Zi +7 more
The radius valley, a dip in the radius distribution of exoplanets at ~1.9 R ⊕, separates compact rocky super-Earths and sub-Neptunes with lower density. Various hypotheses have been put forward to explain the radius valley. Characterizing the radius valley morphology and its correlation to stellar properties will provide crucial observa…
Toward a Unified Explanation for the Three-part Structure of Solar Coronal Mass Ejections
Chen, Yao; Li, Leping; Song, Hongqiang
Coronal mass ejections (CMEs) are associated with the eruption of magnetic flux ropes (MFRs), which usually appear as hot channels in active regions and coronal cavities in quiet-Sun regions. CMEs often exhibit a classical three-part structure in the lower corona when imaged with white-light coronagraphs, including a bright front, dark cavity, and…
Mass Matters: No Evidence for Ubiquitous Lithium Production in Low-mass Clump Giants
Aguilera-Gómez, Claudia; Pinsonneault, Marc H.; Zinn, Joel C. +1 more
Known sources of lithium (Li) in the universe include the Big Bang, novae, asymptotic giant branch stars, and cosmic-ray spallation. During their longer-lived evolutionary phases, stars are not expected to add to the Li budget of the Galaxy, but to largely deplete it. In this context, recent analyses of Li data from GALAH and LAMOST for field red …
Validations and Corrections of the SFD and Planck Reddening Maps Based on LAMOST and Gaia Data
Chen, Bingqiu; Yuan, Haibo; Sun, Yang
Precise correction of dust reddening is fundamental to obtain the intrinsic parameters of celestial objects. The Schlegel et al. (SFD) and the Planck 2D extinction maps are widely used for reddening correction. In this work, using accurate reddening determinations of about 2 million stars from the Large Sky Area Multi-Object Fiber Spectroscopic Te…
A Mini-Neptune from TESS and CHEOPS Around the 120 Myr Old AB Dor Member HIP 94235
Latham, David W.; Quinn, Samuel N.; Kane, Stephen R. +36 more
The Transiting Exoplanet Survey Satellite (TESS) mission has enabled discoveries of the brightest transiting planet systems around young stars. These systems are the benchmarks for testing theories of planetary evolution. We report the discovery of a mini-Neptune transiting a bright star in the AB Doradus moving group. HIP 94235 (TOI-4399, TIC 464…
Four-hundred Very Metal-poor Stars Studied with LAMOST and Subaru. I. Survey Design, Follow-up Program, and Binary Frequency
Shi, Jianrong; Zhao, Gang; Chen, Yuqin +11 more
The chemical abundances of very metal-poor stars provide important constraints on the nucleosynthesis of the first generation of stars and early chemical evolution of the Galaxy. We have obtained high-resolution spectra with the Subaru Telescope for candidates of very metal-poor stars selected with a large survey of Galactic stars carried out with…
Ultraviolet Spectropolarimetry: on the origin of rapidly rotating B stars
Hillier, D. J.; Carciofi, A. C.; Nazé, Y. +12 more
UV spectroscopy and spectropolarimetry hold the key to understanding certain aspects of massive stars that are largely inaccessible (or exceptionally difficult) with optical or longer wavelength observations. As we demonstrate, this is especially true for the rapidly-rotating Be and Bn stars, owing to their high temperatures, geometric asymmetries…
The flaring TESS Objects of Interest: flare rates for all two-minute cadence TESS planet candidates
Howard, Ward S.
Although more than 5000 TESS Objects of Interest have been catalogued, no comprehensive survey of the flare rates of their host stars exists. We perform the first flare survey of all 2250 non-retired TOIs with 2-min cadence light curves to measure or place upper limits on their flare rates. We find 93 candidates orbit flare stars and measure their…
Non-detection of 6Li in Spite plateau stars with ESPRESSO
Lind, Karin; Nordlander, Thomas; Reggiani, Henrique +3 more
The detection of 6Li in Spite plateau stars contradicts the standard big bang nucleosynthesis prediction, known as the second cosmological lithium problem. We measure the isotopic ratio 6Li/7Li in three Spite plateau stars: HD 84937, HD 140283, and LP 815-43. We use 3D non-local thermodynamic equilibrium radiative …