太阳与恒星天体物理

Stars with very low levels of magnetic activity provide an opportunity for a more quantitative comparison with the Sun during its Maunder minimum. We employ spectra from the RAVE survey in a search for particularly low-activity stars with…

Solar wind forecasting plays a crucial role in space weather prediction, yet significant uncertainties persist due to incomplete magnetic field observations of the Sun. Isolating the solar wind forecasting errors due to these effects is…

Galactic archeology has long been limited by a lack of precise masses and ages for metal-poor stars in the Milky Way's thick disk. However, with TESS providing a growing number of photometric observations, it is possible to calculate masses…

This study presents photometric analysis of the intermediate-age open cluster King 6, utilizing photometric data in UBV(RI)$_c$ passband and data from the 2MASS mission. The Gaia DR3 kinematic data were used to estimate the membership…

The Fokker-Planck equation describing the transport of energetic particles interacting with turbulence is difficult to solve analytically. Numerical solutions are of course possible but they are not always useful for applications. In the…

High-resolution helioseismology observations with the Helioseismic and Magnetic Imager (HMI) onboard Solar Dynamics Observatory (SDO) provide a unique three-dimensional view of the solar interior structure and dynamics, revealing a…

The number of known planets around intermediate-mass stars (1.5 M$_{\odot}$ < M$_{\star}$ < 3.5 M$_{\odot}$) is rather low. We aim to test whether the correlation between the metallicity of the star and the presence of gas-giant planets…

Identification of specific stellar populations using photometry for spectroscopic follow-up is a first step to confirm and better understand their nature. In this context, we present an unsupervised machine learning approach to identify…

Lithium is predicted, and observed, to be depleted in contracting, low-mass pre main sequence (PMS) stars. Yet these stars reach the zero age main sequence (ZAMS) with a spread in lithium abundance at a given effective temperature that is…

As part of the IRAM NOEMA Large Program SOLIS, we imaged the protostellar sources SVS13-A and SVS13-B in SiO, SO, CS, and CH3OH at a spatial resolution of 2"-3" (600-900 au). The CS and SO emission traces the 5000 au envelope that hosts the…

In this article, we report the multiwavelength and multiview observations of transverse oscillations of two loop strands induced by a jet-related, confined flare in active region NOAA 13056 on 11 July 2022. The jet originates close to the…

Recurrent chromospheric fan-shaped jets highlight the highly dynamic nature of the solar atmosphere. They have been named as ''light walls'' or ''peacock jets'' in high-resolution observations. In this study, we examined the underlying…

Core-collapse supernova feedback models in hydrodynamical simulations typically assume that all stars evolve as single stars. However, the majority of massive stars are formed in binaries and multiple systems, where interactions with a…

We present a multi-method investigation of four metal-poor G-type main-sequence stars to resolve their Galactic origins. By combining high-resolution spectroscopy from PolarBase, photometric/astrometric data from Gaia DR3, and spectral…

We introduce a new 1D stellar spectral synthesis Python code called stardis. stardis is a modular, open-source radiative transfer code that is capable of spectral synthesis from near-UV to IR for FGK stars. We describe the structure,…

Identifying bifurcated blue straggler (BS) sequences in color-magnitude diagrams (CMDs) of star clusters has long been regarded as a powerful diagnostic for distinguishing different BS formation mechanisms. While such bifurcations are…

We develop an analytic method of inverting the Tolman-Oppenheimer-Volkoff (TOV) relations to high accuracy. In principle, a specified $\mathcal{E}\mbox{-}P$ relation gives a unique $M\mbox{-}R$ relation, and vice-versa. Our method is…

Mass loss through stellar winds governs the evolution of stars on the asymptotic giant branch (AGB). In the case of carbon-rich AGB stars, the wind is believed to be driven by radiation pressure on amorphous carbon (amC) dust forming in the…

We present the first extensive seismic modelling of SX Phe stars in the stellar system $\omega$ Cen. First, using the new values of reddening $E(B-V)$ and distance modulus $(m-M)_V$, and bolometric corrections from Kurucz model atmospheres,…

The Lyman-alpha (Ly{\alpha};1216 {\AA}) line is the brightest emission line in the quiescent solar spectrum and radiates a significant fraction of the available nonthermal energy during flares. Despite its importance, there is a lack of…