太阳与恒星天体物理
Integral field spectroscopy (IFS) offers a distinct advantage for studying extended sources by enabling spatially resolved emission maps for several emission lines without the need for specific filters. This study conducts a detailed…
Our aim is to characterize the effects of the local magnetic fields in quiet regions of stellar atmospheres. We compute magneto-hydrodynamic and purely hydrodynamic simulations of G2V, K0V and M2V star. The magnetic simulations are started…
The circumstellar environments of PNe are wonderful chemically rich astrophysical laboratories in which the ionization of atoms and the formation of simple and complex molecules can be studied. The new high-sensitivity receivers open the…
Context. Quasi-periodic pulsations (QPPs) are an inherent feature of solar and stellar flares. However, the mechanism behind them is debated hence it is necessary to further study them to obtain a complete picture of flares and their…
The understanding of mixing processes in stars is crucial for improving our knowledge of the chemical abundances in stellar photospheres and of their variation with evolutionary phase. This is fundamental for many astrophysical issues on…
Context: Intermediate-mass asymptotic giant branch (AGB) stars influence Galactic lithium evolution by ejecting surface material (including Li) via stellar winds. Internal gravity waves (IGW), excited by convective motions, drive turbulent…
The cluster R136 in the LMC contains a population of stars in excess of 100 M$_\odot$, including R136a1, the most massive star known. Very Massive Stars (VMSs) play an influential role in feedback processes and may potentially produce…
The sub-millimetre dust opacity spectral index is a critical observable to constrain dust properties, such as the maximum grain size of an observed dust population. It has been widely measured at galactic scales and down to protoplanetary…
The masses of white dwarfs (WDs) in intermediate polars (IPs) can be determined from the shape of their hard X-ray spectra. Here we study the importance of all possible systematic uncertainties in this X-ray spectroscopy method, including…
I propose a scenario that allows white dwarfs (WDs) to launch relatively powerful jets when they enter a common envelope evolution (CEE) or experience a grazing envelope evolution (GEE) with a red giant branch star (RGB) or an asymptotic…
Over the past century, the Sun's activity -- which exhibits significant variations -- went through a phase known as the Modern Maximum. Notably, the strongest sunspot cycle on record during this period, and indeed since direct sunspot…
Magnetic AB stars are known to produce periodic radio pulses by the electron cyclotron maser emission (ECME) mechanism. Only 19 such stars, known as 'Main-sequence Radio Pulse emitters' (MRPs) are currently known. The majority of MRPs have…
Solar flare ribbons are believed to map the footpoints of newly reconnected magnetic flux tubes, therefore shedding light on the reconnecting current sheet, which is rarely observed by direct imaging or spectroscopy. Here we study the…
Recent observations and simulations indicate that solar flares undergo extremely complex three-dimensional (3D) evolution, making 3D particle transport models essential for understanding electron acceleration and interpreting flare…
Core-collapse supernovae (CCSNe) are among the primary sources of dust in galaxies. In this study, we derive theoretical upper limits on dust masses as a function of supernova (SN) progenitors with initial masses between 9 and 120 Msun,…
Both star clusters and variable stars are sensitive laboratories of stellar astrophysics and evolution: cluster member stars provide context for interpreting cluster populations, whereas variability reveals the nature of individual stellar…
Utilizing high-resolution imaging and spectroscopic observations from the New Vacuum Solar Telescope (NVST), the Interface Region Imaging Spectrograph (IRIS), and the Solar Dynamics Observatory (SDO), we investigated the nature and origin…
Massive stars play a critical role in the evolution of galaxies, but their formation remains poorly understood. One challenge is accurate measurement of the physical properties of massive protostars, such as current stellar mass, envelope…
Following a type Ia supernova (SN Ia) in a double white dwarf (WD) binary, a surviving WD companion leaves at its orbital velocity $\approx 1$,000 - 3,000 km/s. The Gaia mission has discovered seven such hypervelocity WDs with inflated…
We present the first 3D Radiation-Hydrodynamics simulations of partially-stripped ($M_\mathrm{core}\sim10M_\odot$, $M_\mathrm{env}\sim0.1-1M_\odot$) Yellow Supergiant ($L\sim10^5$, $T_\mathrm{eff}\approx5000-8000$K) envelopes, constructed…