THE ASTRONOMICAL JOURNAL    VOLUME 106, NUMBER 5, PAGE 1839       NOVEMBER 1993

       EARLY-TYPE STARS IN ORTHOGONAL HALO FIELDS. II. IDENTIFICATION OF
                        METAL-RICH A STARS IN THE HALO

                        A. W. RODGERS AND W. H. ROBERTS

 Mount Stromlo and Siding Spring Observatories, Institute of Advanced Studies,
              Australian National University, Canberra, Australia
        Electronic mail: alex@merlin.anu.edu.au, bill@merlin.anu.edu.au

                                   ABSTRACT

    The results of spectrophotometry of the Ca II K and Balmer lines and
    radial velocity measurements for stars earlier than type F0, with 10 <
    V < 15.5 in fields at (l;b) = (90 deg, 270 deg; -45 deg) are reported.
    Slit spectroscopy of 320 stars shows that in this magnitude range there
    are ~80 stars with [Fe/H] > -0.5.  The metal-rich population has a
    vertical scale height of ~600 pc and a space density at the Sun equal
    to 1/225 of the young thin disk A star population.  The metal-rich A
    stars have V_rot = 210 +/- 60 km/s with descreasing angular momentum as
    a function of distance from the Galactic plane.  The line-of-sight
    velocity dispersion is 40 +/- 3 km/s indicating an anomalous relation
    between structure and kinematics.  There is strong evidence that these
    stars are identical in properties to the metal-rich extended
    populations found by Perry [AJ, 74, 139 (1969)] at the NGP and Rodgers
    [AJ, 165, 581 (1971)] at the SGP.