Context : The [ Sr/Ba ] and [ Y/Ba ] scatter observed in some galactic halo stars that are very metal-poor stars and in a few individual stars of the oldest known Milky Way globular cluster NGC 6522 , have been interpreted as evidence of early enrichment by massive fast-rotating stars ( spinstars ) .
Because NGC 6522 is a bulge globular cluster , the suggestion was that not only the very-metal poor halo stars , but also bulge stars at [ Fe/H ] \sim - 1 could be used as probes of the stellar nucleosynthesis signatures from the earlier generations of massive stars , but at much higher metallicity .
For the bulge the suggestions were based on early spectra available for stars in NGC 6522 , with a medium resolution of R \sim 22,000 and a moderate signal-to-noise ratio .

Aims : The main purpose of this study is to re-analyse the NGC 6522 stars previously reported using new high-resolution ( R \sim 45,000 ) and high signal-to-noise spectra ( S/N > 100 ) .
We aim at re-deriving their stellar parameters and elemental ratios , in particular the abundances of the neutron-capture s-process-dominated elements such as Sr , Y , Zr , La , and Ba , and of the r-element Eu .

Methods : High-resolution spectra of four giants belonging to the bulge globular cluster NGC 6522 were obtained at the 8m VLT UT2-Kueyen telescope with the UVES spectrograph in FLAMES-UVES configuration .
The spectroscopic parameters were derived based on the excitation and ionization equilibrium of Fe I and Fe II .

Results : Our analysis confirms a metallicity [ Fe/H ] = -0.95 \pm 0.15 for NGC 6522 , and the overabundance of the studied stars in Eu ( with + 0.2 < [ Eu/Fe ] < + 0.4 ) and alpha-elements O and Mg .
The neutron-capture s-element-dominated Sr , Y , Zr , Ba , La now show less pronounced variations from star to star .
Enhancements are in the range 0.0 < [ Sr/Fe ] < +0.4 , +0.23 < [ Y/Fe ] < +0.43 , 0.0 < [ Zr/Fe ] < +0.4 , 0.0 < [ La/Fe ] < +0.35 , and 0.05 < [ Ba/Fe ] < +0.55 .

Conclusions :