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We study blue horizontal branch (BHB) and RR Lyrae stars in the Rogers et al. (1993a) fields and compare their velocity and density distributions with other surveys in the same part of the sky. Photometric data are given for 176 early-type stars in the northern field. We identify fourteen BHB stars and four possible BHB stars, and determine the selection efficiency of the Century Survey, the HK Survey, and the SDSS survey for BHB stars. We give light curves and gamma -radial velocities for three type-ab RR Lyrae stars in the northern field; comparison with the nearby LONEOS Survey shows that there is likely to be an equal number of lower-amplitude type-ab RR Lyrae stars that we do not find. There are therefore at least twice as many BHB stars as type-ab RR Lyrae stars in the northern field--similar to the ratio in the solar neighborhood. The velocity distribution of the southern field shows no evidence for an anomalous thick disk that was found by Gilmore et al. (2002); the halo velocity peaks at a slightly prograde rotational velocity but there is also a significant retrograde halo component in this field. The velocity distribution in the northern field shows no evidence of Galactic rotation for |Z|>4 kpc and a slight prograde motion for |Z|<4 kpc. The space densities of BHB stars in the northern field agree with an extrapolation of the power-law distribution recently derived by de Propris et al. (2010). For |Z|<4 kpc, however, we observe an excess of BHB stars compared with this power-law. We conclude that these BHB stars mostly belong to a spatially flattened, non-rotating inner halo component of the Milky Way in confirmation of the Kinman et al. (2009) analysis of Century Survey BHB stars.
The magnetic field plays an important role in every stage of the star-formation process from the collapse of the initial protostellar core to the stars arrival on the main sequence. Consequently, the goal of this science case is to explore a wide ran
We identify 51 blue horizontal branch (BHB) stars, 12 possible BHB stars and 58 RR Lyrae stars in Anticentre fields. Their selection does not depend on their kinematics. Light curves and ephemerides are given for 7 previously unknown RR Lyrae stars.
We present new identifications of five red giant stars in the Galactic halo with chemical abundance patterns that indicate they originally formed in globular clusters. Using data from the Apache Point Observatory Galactic Evolution Experiment (APOGEE
We report the first high spatial resolution measurement of magnetic fields surrounding LkH$alpha$ 101, a part of the Auriga-California molecular cloud. The observations were taken with the POL-2 polarimeter on the James Clerk Maxwell Telescope within
[abridged] The severe crowding in the direction of the inner Milky Way suggests that the census of stars within a few tens of parsecs in that direction may not be complete. We search for new nearby objects companions of known high proper motion (HP