相关论文: Magnetic fields of young solar twins
The surface rotation rates of young solar-type stars vary rapidly with age from the end of the pre-main sequence through the early main sequence. Important changes in the dynamos operating in these stars may result from this evolution,…
By studying young magnetically active late-type stars, i.e. analogues to the young Sun, one can draw conclusions on the evolution of the solar dynamo. We determine the topology of the surface magnetic field and study the relation between…
There is a large change in surface rotation rates of sun-like stars on the pre-main sequence and early main sequence. Since these stars have dynamo driven magnetic fields, this implies a strong evolution of their magnetic properties over…
The surface rotation rates of young solar-type stars decrease rapidly with age from the end of the pre-main sequence though the early main sequence. This suggests that there is also an important change in the dynamos operating in these…
Surface rotation rates of young solar-type stars display drastic changes at the end of the pre-main sequence through the early main sequence. This may trigger corresponding changes in the magnetic dynamos operating in these stars, which…
Global magnetic fields of active solar-like stars are nowadays routinely detected with spectropolarimetric measurements and are mapped with Zeeman-Doppler imaging (ZDI). However, due to the cancellation of opposite field polarities,…
Planets orbiting young, solar-type stars are embedded in a more energetic environment than that of the solar neighbourhood. They experience harsher conditions due to enhanced stellar magnetic activity and wind shaping the secular evolution…
Our understanding of magnetic fields in late-type stars is strongly driven by what we know of the solar magnetic field. For this reason, it is crucial to understand how typical the solar dynamo is. To do this we need to compare the solar…
A significant fraction of massive main-sequence stars show strong, large-scale magnetic fields. The origin of these fields, their lifetimes, and their role in shaping the characteristics and evolution of massive stars are currently not well…
We present an analysis of infrared (IR) echelle spectra of five stars in the TW Hydrae Association (TWA). We model the Zeeman broadening in four magnetic-sensitive \ion{Ti}{1} lines near $2.2 \mu$m and measure the value of the photospheric…
The evolution of magnetic fields in Ap stars during the main sequence phase is presently mostly unconstrained by observation because of the difficulty of assigning accurate ages to known field Ap stars. We are carrying out a large survey of…
For several decades we have been cognizant of the presence of magnetic fields in early-type stars, but our understanding of their magnetic properties has recently (over the last decade) expanded due to the new generation of high-resolution…
Strong, globally-organized magnetic fields are found for a small fraction of O, B, and A stars. At the same time, many theoretical and indirect observational studies suggested ubiquitous presence of weak localized magnetic fields at the…
Neutron stars radiate in a broad band spectrum from radio wavelengths up to very high energies. They have been sorted into several classes depending on their respective place in the $P-\dot{P}$ diagram and depending on spectral/temporal…
The magnetic activity of the Sun changes with the solar cycle. Similar cycles are found in other stars as well, but their details are not known to a similar degree. Characterising stellar magnetic cycles is important for the understanding…
Weak magnetic fields have recently been detected in Vega and Sirius. Here, we explore the possibility that these fields are the remnants of some field inherited or created during or shortly after star formation and, unlike true fossil…
The surface magnetic fields of pre-main-sequence stars and zero-age main-sequence stars are notably strong, resulting in the generation of numerous spots and the emission of bright chromospheric lines. Rotational variations in magnetic…
About 5% of upper main sequence stars are permeated by a strong magnetic field, the origin of which is still matter of debate. With this work we provide observational material to study how magnetic fields change with the evolution of stars…
Aims. In this paper, we aim to measure the strength of the surface magnetic fields for a sample of five intermediate mass T Tauri stars and one low mass T Tauri star from late-F to mid-K spectral types. While magnetic fields of T Tauri…
We investigate how the observed large-scale surface magnetic fields of low-mass stars (~0.1 -- 2 Msun), reconstructed through Zeeman-Doppler imaging (ZDI), vary with age t, rotation and X-ray emission. Our sample consists of 104 magnetic…