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NGC 6522 has been the first metal-poor globular cluster identified in thebulge by W. Baade. Despite its importance, very few high resolution abundanceanalyses of stars in this cluster are available in the literature. The bulgemetal-poor clusters may be important tracers of the early chemical enrichmentof the Galaxy. The main purpose of this study is the determination ofmetallicity and elemental ratios in individual stars of NGC 6522. Highresolution spectra of 8 giants of the bulge globular cluster NGC 6522 wereobtained at the 8m VLT UT2-Kueyen telescope with the FLAMES+GIRAFFEspectrograph. Multiband V,I,J,Ks} photometry was used to derive effectivetemperatures as reference values. Spectroscopic parameters are derived from FeIand FeII lines, and adopted for the derivation of abundance ratios. The presentanalysis provides a metallicity [Fe/H] = -1.0+-0.2. The alpha-elements Oxygen,Magnesium and Silicon show [O/Fe]=+0.4, [Mg/Fe]=[Si/Fe]= +0.25, whereas Calciumand Titanium show shallower ratios of [Ca/Fe]=[Ti/Fe]=+0.15. Theneutron-capture r-process element Europium appears to be overabundant by[Eu/Fe]=+0.4. The neutron-capture s-elements La and Ba are enhanced by[La/Fe]=+0.35 and [Ba/Fe]=+0.5. The large internal errors, indicating the largestar-to-star variationin the Ba and Eu abundances, are also discussed. Themoderate metallicity combined to a blue Horizontal Branch (BHB), arecharacteristics similar to those of HP~1 and NGC 6558, pointing to a populationof very old globular clusters in the Galactic bulge. Also, the abundance ratiosin NGC 6522 resemble those in HP 1 and NGC 6558. The ultimate conclusion isthat the bulge is old, and went through an early prompt chemical enrichment.

VLT-FLAMES Analysis of 8 giants in the Bulge Metal-poor Globular Cluster NGC 6522: Oldest Cluster in the Galaxy?