Kimberly Ward-Duong, Amherst College

Unlike the Sun, the vast majority of the nearest stars are known as M-dwarf stars: small, dim, red stars that make up over 70% of the stars in our galaxy. Given their great abundance and the relative ease of detecting their planets, M-dwarfs form ideal targets for large upcoming exoplanet searches and surveys. Together with their lower-mass brown dwarf counterparts, the lowest-mass stars are prime systems for detailed study at high resolution, using techniques ranging from optical/infrared observations out to radio wavelengths. In this talk, I will describe the companions and environments of the nearest low-mass star systems, and efforts to study dusty disks surrounding the smallest stars in young, nearby star-forming regions. To search for companion stars to our nearest M-dwarf neighbors, adaptive optics imaging provides a sensitive technique to identify binary stars with a wide range of orbital separations. This allows us to better explore the similarities and differences between low-mass stars, solar-type stars more akin to our Sun, and the most massive nearby stars. These techniques can also be used to study the atmospheres of even lower-mass objects, known as brown dwarfs, using instruments such as the Gemini Planet Imager. To investigate planet-forming environments around young stars, observations at submillimeter wavelengths with telescopes like ALMA provide a window into the amount of dusty material available to form planets. Results from these studies show a decrease in dust content around stars from ~1 to ~10 Myr, suggesting characteristic timescales for planet formation. Observations have also revealed smaller amounts of dust in disks around lower-mass stars, which may help explain the rare occurrence of Jupiter-like planets orbiting M-dwarfs.