Metallicity analysis of Bulge Globular Clusters

D. GEISLER; M.C. PARISI; F. MAURO; R. COHEN; S. VILLANOVA

Córdoba

Congreso; Friends of Friends Meeting; 2018

P { margin-bottom: 0.25cm; line-height: 120%; }It has been recognized for a long time that our Galaxy contains atleast two populations of Globular Clusters: one associated with thehalo and the other with Disco/Bulge of the Milky Way (BGC). Bothpopulations strongly trace the chemical and dynamic properties of therespective Galactic components. While the Globular Clusters of thehalo have been studied in great detail, the BGC have been relativelyneglected, mainly due to the high interstellar reddening. The VistaVariables in the Via Lactea survey (VVV) has been an importantadvance for the infrared study of the Galaxy´s BGC system. However,there are two fundamental parameters of these objects that the VVVcan not provide with the required precision: radial velocities (VR)and metallicities. The most efficient way to derive these importantparameters is through the near infrared spectroscopic observation ofthe Ca II Triplet lines (CaT - λ ≈ 8500 Å). In this work, wepresent preliminary results of a sample of BGC studied with the CaTtechnique, through observations obtained with the FORS2 instrument ofthe VLT (Chile). Our results will not only contribute to theunderstanding of the distribution of metallicities and VRs of the CGBsystem, but will also provide information on possible interestingobjects for the search, by means of high dispersion spectroscopy, ofmultiple populations in BGC.