相关论文: The lithium-rotation connection in the newly disco…

ASCC 123 is a little-studied young and dispersed open cluster. Recently, we conducted the first research devoted to it. In this paper, we complement our previous work with TESS photometry for the 55 likely members of the cluster. We pay…

The large separation in the low radial order regime is considered as a highly valuable observable to derive mean densities of $\delta$ Scuti stars, due to its independence with rotation. Up to now, theoretical studies of this…

In the Gaia era, the majority of stars in the Solar neighbourhood have parallaxes and proper motions precisely determined while spectroscopic age indicators are still missing for a large fraction of low-mass young stars. In this work we…

Despite the extensive study of lithium depletion during pre-main-sequence contraction, studies of individual stars show discrepancies between ages determined from the HR diagram and ages determined from lithium depletion (Song et al. 2002,…

Runaway stars are characterised by their remarkably high space velocities, and the study of their formation mechanisms has attracted considerable interest. Young, nearby runaway stars are the most favorable for identifying their place of…

Using high-resolution, high quality spectra we investigate the presence of $^6$Li in two lithium-poor stars that host extrasolar planetary systems. We present improved atomic and molecular line lists for the region in the vicinity of the…

I present the results of a programme to monitor the strengths of the Li I 6708A, K I 7699A and chromospheric Halpha lines in a group of cool Pleiades stars. Consistent instrumentation and analysis techniques are used to show that there is…

Thanks to the high multiplex and efficiency of Giraffe at the VLT we have been able for the first time to observe the Li I doublet in the Main Sequence (MS) stars of a Globular Cluster. At the same time we observed Li in a sample of…

We have acquired high-resolution optical spectroscopy for a sample of T Tauri stars (TTSs) in open clusters using Hydra on the WIYN 3.5m telescope, and present projected rotational velocities (v sin i values) for 54 stars in IC 5070 and 99…

We present high resolution spectroscopy of a sample of 24 solar-type stars in the young (15-40 Myr), open cluster, NGC 2547. We use our spectra to confirm cluster membership in 23 of these stars, determine projected equatorial velocities…

We analise the behavior of lithium abundance as a function of effective temperature, projected rotational velocity, orbital period and eccentricity for a sample of 68 binary systems with giant component and orbital period ranging from about…

The orbital angular momentum of a close-orbiting giant planet can be sufficiently large that, if transferred to the envelope of the host star during the red giant branch (RGB) evolution, it can spin-up the star's rotation to unusually large…

The depletion of lithium during the pre-main sequence and main sequence phases of stellar evolution plays a crucial role in the comparison of the predictions of big bang nucleosynthesis with the abundances observed in halo stars. In the…

The low spin rates measured for solar-type stars at an age of a few Myr (~10% of the break-up velocity) indicate that some mechanism of angular momentum regulation must be at play in the early pre-main sequence. We characterize the rotation…

High-dispersion spectra centered on the Li 6708 A line have been obtained for 70 potential members of the open cluster NGC 3680, with an emphasis on stars in the turnoff region. A measurable Li abundance has been derived for 53 stars, 39 of…

The surface content of lithium (Li) and beryllium (Be) in stars can reveal important information about the temperature structure and physical processes in their interior regions. This study focuses on solar-type stars with a sample that is…

An important aspect in the evolutionary scenario of cool stars is their rotation and the rotationally induced magnetic activity and interior mixing. Stars in open clusters are particularly useful tracers for these aspects because of their…

As a test of rotationally-induced mixing causing the well-known Li dip in older mid-F dwarfs in the local Galactic disk, we utilize high-resolution and -S/N Keck/HIRESspectroscopy to measure the Li abundance in the components of the1 Gyr,…

We have investigated a group of stars known to have low chromospheric ages, but high kinematical ages. Isochrone, chemical and lithium ages are estimated for them. The majority of stars in this group show lithium abundances much smaller…

Young (125 Myr), populous ($>$1000 members), and relatively nearby, the Pleiades has provided an anchor for stellar angular momentum models for both younger and older stars. We used K2 to explore the distribution of rotation periods in the…