Paper detail

Beta Pictoris and AB Doradus Moving Groups: Likely New Low-Mass Members

We present results from our continuing program to identify new, low-mass, members of the nearby young moving groups (NYMGs) using a proper motion selection algorithm and various observational techniques. We have three goals: 1) To provide high priority targets for exoplanet searches by direct imaging, 2) To complete the census of the membership in the NYMGs down to ~0.1 Msun, and thus 3) Provide a well-characterized sample of nearby (median distances at least twice as close as the Taurus and Ophiuchus SFR's), young (8-50 Myr) stars for detailed study of their physical properties and multiplicity. Our program proceeds as follows: we apply the selection algorithm to a proper motion catalog where initial selection cuts of candidate members are based on the mean motion of known NYMG members and the proper motions and photometric distances of the candidates. NYMG membership is investigated further using possible signs of youth, including H-alpha emission and X-ray flux, and then verified through radial velocity (RV) measurements. We identify TYC 1766-1431-1 (M3), TYC 1208-468-1 and 2 (K3), TYC 7558-655-1 (K5), and PM I04439+3723W and E (M3) as likely members of the Beta Pictoris moving group (BPMG) and TYC 1741-2117-1N and S (K7), TYC 1752-63-1 (K7), TYC 523-573-1 (K7), and TYC 4943-192-1 (M0) as likely members of the AB Doradus moving group (ABDMG). We also rule out the membership of several BPMG and ABDMG candidates. To date our program has identified 16 new NYMG members of spectral type K3 or later.