太阳与恒星天体物理
About fifteen years ago a new type of extreme (with kinetic energies of $\mathrm{E}_k \sim 10^{47-49}\, \mathrm{erg}$) molecular outflows associated with very luminous ($\geq 10^5\, \mathrm{L}_\odot$) and massive (10$^3$ M$_\odot$) young…
The common envelope (CE) phase is a key stage in binary star evolution that is still not very well understood. Once engulfed by the giant star, the binary companion may accrete envelope material. For neutron star (NS) companions, such…
A detailed analysis of the impulsive C2.8 solar flare SOL2023-03-19T02:12 is presented, focusing on the microwave (MW) and X-ray domains. The flare was selected because of its impulsive nature, the relatively simple magnetic morphology of…
The population of close double white dwarfs (DWDs) in the Milky Way will make up the largest population of sources resolved by LISA, with a subset of the population having three-dimensional position and chirp mass measurements obtained from…
Globular Clusters (GCs) host multiple stellar populations, likely composed of a subset of FG stars that enriched the intracluster medium and gave rise to SG stars, each characterised by distinctive chemical patterns. These patterns…
We present results from a spectroscopic survey of 32 FGK stars hosting brown dwarfs, using high-resolution optical spectra (R = 130,000 and 50,000) obtained with the PEPSI spectrograph on the Large Binocular Telescope. The primary goal of…
Constraining ionization and excitation processes in protoplanetary disks is essential for understanding the chemical structure and evolution of disk material, shaping planet formation pathways. We present JWST/NIRSpec IFU observations of…
There are indirect signs of the presence of a companion near the star CQ\,Tau. A period of 10\;years was found in the brightness changes. The image of the disk shows an extensive cavity with a size of about 25~AU, surrounded by a dust ring…
Numerical modeling of solar plasma dynamics is affected by the resolution of the computational grid. This often requires the estimation of subgrid processes related to the small-scale flow turbulence, as these processes play a critical role…
We have analyzed archival FUV and optical spectra of the hot halo star HD 177566. The star has an effective temperature $T_{\rm eff} = 33{,}000 \pm 1000$ K, surface gravity $\log g = 3.79 \pm 0.11$, and helium abundance $\log N({\rm…
We present a sample of coherent and stable photometric period determinations for cataclysmic variables, based on TESS photometry through sector 102. We analyzed a total of 1557 cataclysmic variable stars and detected periodic variations in…
Quasi-periodic fast-mode magnetoacoustic waves are often detected during solar flare events, although they are not observed in every flare, due to observational signal-to-noise limits and differences in flare magnetic topology and energy…
This article is focused on the analysis of observational data and improvement of orbital solutions of 8 objects. The listed objects are members of a sample of approximately 300 nearby (d < 100 pc) multiple systems compiled for long-term…
The solar corona exhibits a pronounced temperature inversion, with plasma temperatures increasing by nearly two orders of magnitude from the chromosphere to the corona. We investigate how spatially sparse and temporally intermittent…
Solar filament eruptions are central to coronal mass ejections and space weather, yet their triggering mechanisms remain a fundamental open question. In particular, the early-stage that drives a magnetic flux rope toward instability and its…
Surveys of Galactic halo stars have revealed numerous streams and substructures tracing stellar populations accreted by the Milky Way. Among these, Gaia-Sausage-Enceladus (GSE) and Sequoia are the most prominent, both associated with dwarf…
It remains evasive whether solar active regions (ARs) obeying or violating Hale's polarity law, Joy's tilt law, and the hemispheric helicity rule (HHR) differ in flare productivity. Here we conduct a comprehensive statistical analysis of…
M dwarfs are prime targets for discovering exoplanets, and the nearest M dwarfs to the Sun provide among the best opportunities for follow-up detailed exoplanet characterization. GJ 729, the seventh closest M dwarf to the Sun, presents…
Magnetic geometry shapes how turbulence transports and dissipates energy in strongly magnetized plasmas. The solar corona, a maze of open and closed flux tubes with sharp transverse gradients, is a prominent example, yet most…
Turbulence in the solar interior and atmosphere plays a crucial role in energy transport, yet modeling its subgrid-scale effects remains a major challenge. This study leverages machine learning (ML) models to predict components of the…