Puzzling Locations of Mildly Metal-Poor Stars in the HR
Location in the HR diagram of stars in the metallicity range
[-2.2 < [Fe/H] < -1.8] and comparison with the
[Fe/H] = -1.98 Bergbusch and Vandenberg (1992) 14 Gyrs isochrone
(dotted line). The shift needed in Teff is indicated by
the arrow. Dashed lines show 12 and 16 Gyrs similarly shifted isochrones.