Chemical abundances of four red supergiants star clusters (RSGCs) in Scutum-Crux arm. Issue Volume 14:Issue S351(2019) (May 2019)

• Record Type: Journal Article
• Authors: Chun, Sang-Hyun
• Editors: Bragaglia, Angela; Davies, Melvyn; Sills, Alison; Vesperini, Enrico
• Is Part Of: Proceedings of the International Astronomical Union. Volume 14:Issue S351(2019)
• Page Start: 189
• Page End: 191
• Publication Date: 2019-05
• Subjects: stars: abundances, -- stars: late-type, -- (stars:) supergiants, -- Galaxy: disk; Astronomy -- Congresses; Astronomy -- Periodicals; 520
• DOI: 10.1017/S1743921319006902
• Languages: English
• ISSNs: 1743-9213

Abstract

Abstract: We investigate the spectral properties of red supergiant stars in the four RSGCs (RSGC2, RSGC3, RSGC4, RSGC5, and Alicante 10) in the Scutum-Crux arm of the Milky Way. The high-resolution ( R : 45, 000) near-infrared ( H and K bands) spectra for 41 red supergiants were obtained using IGRINS at Gemini South telescope. The calibration of effective temperatures and gravities are derived based on the EW Ti and EW CO using supergiants in IGIRNS library. The resulted temperatures and gravities are consistent with previous results. Model spectra were synthesized using derived stellar parameters from which we estimate metallicities and chemical abundances like α-elements. In our preliminary result, we find that overall four RSGCs indeed have sub-solar metallicities as already known in previous studies. The metallicity properties of RSGCs are far off the nominal metallicity trend in this region, and this suggests recent low-metallicity gas fueling into the inner disk and bulge.