(a) Distribution of distance from the Galactic plane, (b) kinematic diagram, and (c) relation between metallicity and distance from the Galactic plane for RR Lyrae stars with [Fe /H ] > -0.95. The curve in the left panel approximates the distribution with an exponential law with scale height ZO. The solid line in the middle panel is a regression line, whose slope is determined by the subsystem’s rotation rate; the open circles and dashed line correspond to stars with [Fe/H] > -0.4, and the filled circles and dashed line to stars with -0.95 < [Fe/H] < -0.4. The line in the right panel is a least-squares regression line for | Z | < 2 kpc, whose slope is determined by the metallicity gradient;the squares show distant stars excluded from our computations.
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