Gemini/Phoenix H-band analysis of the globular cluster AL 3

• Autor(a) principal: Barbuy, Beatriz
• Data de Publicação: 2021
• Outros Autores: Ernandes, Heitor, Souza, Stefano O., Razera, Roberta Ferreira, Moura, Tatiana, Meléndez, Jorge, Pérez Villegas, Maria de Los Angeles, Zoccali, Manuela, Minniti, Dante, Dias, Bruno Moreira de Souza, Ortolani, Sergio, Bica, Eduardo Luiz Damiani
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UFRGS
• Texto Completo: http://hdl.handle.net/10183/237350
• topic: Aglomerados globulares; Fotometria estelar; Metalicidade; Bojos de galaxias; Stars: abundances; Stars: atmospheres; Galaxy: bulge; Globular clusters: individual: NGC 6558; Globular clusters: individual: AL 3; Globular clusters: individual: HP 1

The globular cluster AL 3 is old and located in the inner bulge. Three individual stars were observed with the Phoenix spectrograph at the Gemini South telescope. The wavelength region contains prominent lines of CN, OH, and CO, allowing the derivation of C, N, and O abundances of cool stars. Aims. We aim to derive C, N, O abundances of three stars in the bulge globular cluster AL 3, and additionally in stars of NGC 6558 and HP 1. The spectra of AL 3 allows us to derive the cluster’s radial velocity. Methods. For AL 3, we applied a new code to analyse its colour-magnitude diagram. Synthetic spectra were computed and compared to observed spectra for the three clusters. Results. We present a detailed identification of lines in the spectral region centred at 15 555 Å, covering the wavelength range 15 525– 15 590 Å. C, N, and O abundances are tentatively derived for the sample stars.