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We present metallicities of 2690 RR0 Lyrae stars observed toward the MACHOSurvey fields in the Galactic Bulge. These [Fe/H] values are based upon anempirically calibrated relationship that uses the Fourier coefficients of thelight curve and are accurate to ~0.2 dex. The majority of the RR0 Lyrae starsin our sample are located in the Galactic Bulge, but 255 RR0 stars areassociated with Sagittarius dwarf galaxy. We find that the RR0 Lyrae stars thatbelong to the Galactic Bulge have average metallicities [Fe/H] = -1.25, with abroad metallicity range from [Fe/H] = -2.26 to -0.15. The RR0 stars fromSagittarius dwarf galaxy have lower average metallicity of [Fe/H] = -1.55 \pm0.02, with an intrinsic dispersion of 0.25 dex, similar to that in the bulge. Acorrelation between metallicity and galactocentric distance is found, in asense that for the metal-poor RR0 Lyrae stars ([Fe/H]< -1.5 dex), the closer astar is to the Galactic center, on average, the more metal rich it is. However,for the metal-rich RR0 Lyrae stars ([Fe/H] > -1.2 dex), this trend is reversed.Using mean magnitudes of MACHO RR Lyrae stars, we searched for the evidence ofthe Galactic bar, and found marginal evidence of a bar. The absence of a strongbar indicates that the RR Lyrae in the bulge represent a different populationthan the majority of the bulge stars, which are metal rich and are part of abar.

Metallicity Analysis of MACHO Galactic Bulge RR0 Lyrae stars from their Lightcurves