▪ Abstract Until the late 1990s the rich Hyades and the sparse UMa clusters were the only
coeval, comoving concentrations of stars known within 60 pc of Earth. Both are hundreds of …

BANYAN Σ is a new Bayesian algorithm to identify members of young stellar associations
within 150 pc of the Sun. It includes 27 young associations with ages in the range∼ 1–800 …

Aims. We study the evolution of the rotation and the high energy X-ray, extreme ultraviolet
(EUV), and Ly-α emission for F, G, K, and M dwarfs, with masses between 0.1 and 1.2 M⊙ …

Context. The relevance of M dwarfs in the search for potentially habitable Earth-sized
planets has grown significantly in the last years. Aims. In our on-going effort to …

We present a self-consistent, absolute isochronal age scale for young (≲ 200 Myr), nearby
(≲ 100 pc) moving groups in the solar neighbourhood based on homogeneous fitting of …

Abstract The Apache Point Observatory Galactic Evolution Experiment (APOGEE), one of the
programs in the Sloan Digital Sky Survey III (SDSS-III), has now completed its systematic …

We combine optical, near-infrared, and mid-infrared spectra and photometry to construct
expanded spectral energy distributions for 145 field age (> 500 Myr) and 53 young (lower …

We determined effective temperatures, surface gravities, and metallicities for a sample of
343 M dwarfs observed with CARMENES, the double-channel, high-resolution spectrograph …

Angular differential imaging is a high-contrast imaging technique that reduces quasistatic
speckle noise and facilitates the detection of nearby companions. A sequence of images is …

We have developed a one-dimensional photochemical and thermochemical kinetics and
diffusion model to study the effects of disequilibrium chemistry on the atmospheric …