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GRB 240529A: A Tale of Two Shocks
DOI: 10.3847/2041-8213/ad85da Bibcode: 2024ApJ...976L..20S

Fang, Min; Liu, Hao; Liu, Wei +66 more

Thanks to the rapidly increasing time-domain facilities, we are entering a golden era of research on gamma-ray bursts (GRBs). In this Letter, we report our observations of GRB 240529A with the Burst Optical Observer and Transient Exploring System, the 1.5 m telescope at Observatorio de Sierra Nevada, the 2.5 m Wide Field Survey Telescope of China,…

2024 The Astrophysical Journal
Gaia 8
New Insights into the Internal Structure of GJ 1214 b Informed by JWST
DOI: 10.3847/2041-8213/ad615b Bibcode: 2024ApJ...970L..28N

Eastman, Jason D.; Bean, Jacob L.; Zhang, Michael +7 more

Recent JWST observations of the sub-Neptune GJ 1214 b suggest that it hosts a high-metallicity (≳100× solar), hazy atmosphere. Emission spectra of the planet show molecular absorption features, most likely due to atmospheric H2O. In light of this new information, we conduct a thorough reevaluation of the planet's internal structure. We …

2024 The Astrophysical Journal
JWST 8
Stellar Evolution in Real Time. II. R Hydrae and an Open-Source Grid of >3000 Seismic TP-AGB Models Computed with MESA
DOI: 10.3847/1538-4357/ad534a Bibcode: 2024ApJ...971..186J

Tayar, Jamie; Joyce, Meridith; Molnár, László +3 more

We present a comprehensive characterization of the evolved thermally pulsing asymptotic giant branch (TP-AGB) star R Hydrae (R Hya), building on the techniques applied in Stellar Evolution in Real Time I (Molnár et al.) to T Ursae Minoris. We compute over 3000 theoretical TP-AGB pulse spectra using MESA and the corresponding oscillation spectra wi…

2024 The Astrophysical Journal
Gaia 8
New Chorus Diffusion Coefficients for Radiation Belt Modeling
DOI: 10.1029/2023JA031607 Bibcode: 2024JGRA..12931607W

Meredith, Nigel P.; Wong, Jin-Mann; Horne, Richard B. +2 more

Whistler mode chorus is an important magnetospheric wave emission playing a major role in radiation belt dynamics, where it contributes to both the acceleration and loss of relativistic electrons. In this study we compute bounce and drift averaged chorus diffusion coefficients for 3.0 < L* < 6.0, using the TS04 external magnetic field model,…

2024 Journal of Geophysical Research (Space Physics)
Cluster DoubleStar 8
On the origin of accretion bursts in FU Ori
DOI: 10.1093/mnras/stae049 Bibcode: 2024MNRAS.528.2182N

Nayakshin, Sergei; Elbakyan, Vardan

Accretion luminosity of young star FU Ori (FUOR) increased from undetectable levels to hundreds of L in 1937 and remains nearly as high at the present time. In a recent paper, we showed how Extreme Evaporation (EE) of a young gas giant planet that migrated to a ~10 d orbit around the star may power FUOR. However, our model assumed a po…

2024 Monthly Notices of the Royal Astronomical Society
Gaia 8
Dwarf galaxies in the MATLAS Survey: Hubble Space Telescope observations of the globular cluster systems of 74 ultra-diffuse galaxies
DOI: 10.1051/0004-6361/202449617 Bibcode: 2024A&A...690A.339M

Müller, Oliver; Duc, Pierre-Alain; Lim, Sungsoon +7 more

Ultra-diffuse galaxies (UDGs), characterised by their low surface brightness and large physical size, constitute a subclass of dwarf galaxies that challenge our current understanding of galaxy formation and evolution. In this paper, we probe the properties of 74 UDGs, identified in the MATLAS survey, based on a comprehensive study of their globula…

2024 Astronomy and Astrophysics
eHST 8
Methods for Incorporating Model Uncertainty into Exoplanet Atmospheric Analysis
DOI: 10.3847/1538-4357/ad354e Bibcode: 2024ApJ...966..156N

McGill, Peter; Kempton, Eliza M. -R.; Nixon, Matthew C. +1 more

A key goal of exoplanet spectroscopy is to measure atmospheric properties, such as abundances of chemical species, in order to connect them to our understanding of atmospheric physics and planet formation. In this new era of high-quality JWST data, it is paramount that these measurement methods are robust. When comparing atmospheric models to obse…

2024 The Astrophysical Journal
eHST 8
LAMOST J1010+2358 is not a Pair-Instability Supernova Relic
DOI: 10.33232/001c.122335 Bibcode: 2024OJAp....7E..66T

Cerny, William; Simon, Joshua D.; Ji, Alexander P. +2 more

The discovery of a star formed out of pair-instability supernova ejecta would have massive implications for the Population III star initial mass function and the existence of stars over 100 Msun, but none have yet been found. Recently, the star LAMOST J1010+2358 was claimed to be a star that formed out of gas enriched by a pair-instability superno…

2024 The Open Journal of Astrophysics
Gaia 8
Asteroseismic signatures of core magnetism and rotation in hundreds of low-luminosity red giants
DOI: 10.1093/mnras/stae2053 Bibcode: 2024MNRAS.534.1060H

Li, Gang; Chaplin, William J.; Davies, Guy R. +6 more

Red giant stars host solar-like oscillations which have mixed character, being sensitive to conditions both in the outer convection zone and deep within the interior. The properties of these modes are sensitive to both core rotation and magnetic fields. While asteroseismic studies of the former have been done on a large scale, studies of the latte…

2024 Monthly Notices of the Royal Astronomical Society
Gaia 8
The robustness in identifying and quantifying high-redshift bars using JWST observations
DOI: 10.1051/0004-6361/202348539 Bibcode: 2024A&A...688A.158L

Ho, Luis C.; Fang, Taotao; Yu, Si-Yue +1 more

Understanding the methodological reliability in identifying and quantifying high-redshift bars is essential for studying their evolution with the James Webb Space Telescope (JWST). We used nearby spiral galaxies to generate simulated images at various resolutions and signal-to-noise ratios, and obtained the simulated galaxy images observed in the …

2024 Astronomy and Astrophysics
JWST 8