New uvby-β data are provided for 442 high-velocity and metal-poor stars; 90 of these stars have been observed previously by us, and 352 are new. When combined with our previous two photometric catalogues, the data base is now made up of 1533 high-velocity and metalpoor stars, all with uvby-β photometry and complete kinematic data, such as proper motions and radial velocities taken from the literature. −0.4, 160, 10.0, 45.8). The seven most metal-poor halo groups, −2.31 ≤ [Fe/H] ≤ −1.31, show a mean age of 13.0 ± 0.2 (mean error) Gyr, giving a mean difference from the WMAP results for the age of the Universe of 0.7 ± 0.3 Gyr. These results for the ages and components of the thick disk and for the age of the Galactic halo field stars are discussed in terms of various models and ideas for the formation of galaxies and their stellar populations.

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