Chrono-chemodynamical analysis of the globular cluster NGC 6355: Looking for the fundamental bricks of the Bulge

被引：7

作者：

Souza, S. O. ^{[1
,2
]}

Ernandes, H. ^{[2
,3
]}

Valentini, M. ^{[1
]}

Barbuy, B. ^{[2
]}

Chiappini, C. ^{[1
]}

Perez-Villegas, A. ^{[4
]}

Ortolani, S. ^{[5
,6
,7
]}

Friaca, A. C. S. ^{[2
]}

Queiroz, A. B. A. ^{[1
,8
]}

Bica, E. ^{[9
]}

机构：

[1] Leibniz Inst Astrophys Potsdam AIP, Sternwarte 16, D-14482 Potsdam, Germany

[2] Univ Sao Paulo, IAG, Rua Matao 1226, Cidade Univ, BR-05508900 Sao Paulo, Brazil

[3] Lund Univ, Dept Astron & Theoret Phys, Lund Observ, Box 43, S-22100 Lund, Sweden

[4] Univ Nacl Autonoma Mexico, Inst Astron, AP 106, Ensenada 22800, BC, Mexico

[5] Univ Padua, Dipartimento Astron, Vicolo Osservatorio 2, I-35122 Padua, Italy

[6] INAF Osservatorio Astron Padova, Vicolo Osservatorio 5, I-35122 Padua, Italy

[7] Ctr Ateneo Studi & Att Spaziali Giuseppe Colombo C, Via Venezia 15, I-35131 Padua, Italy

[8] Univ Potsdam, Inst Phys & Astron, Haus 28 Karl Liebknecht Str 24-25, D-14476 Potsdam, Germany

[9] Univ Fed Rio Grande do Sul, Dept Astron, CP 15051, BR-91501970 Porto Alegre, Brazil

来源：

ASTRONOMY & ASTROPHYSICS | 2023年 / 671卷

基金：

巴西圣保罗研究基金会;

关键词：

Galaxy; bulge; globular clusters; individual; NGC; 6355; stars; abundances; atmospheres; Hertzsprung-Russell and C-M diagrams; kinematics and dynamics; UV LEGACY SURVEY; RR LYRAE STARS; RESOLUTION ABUNDANCE ANALYSIS; VELOCITY DISPERSION PROFILES; MULTIPLE STELLAR POPULATIONS; INNER MILKY-WAY; GALACTIC BULGE; RED GIANTS; METALLICITY DISTRIBUTION; PROPER MOTIONS;

D O I：

10.1051/0004-6361/202245286

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

The information on Galactic assembly time is imprinted on the chemodynamics of globular clusters. This makes them important probes that help us to understand the formation and evolution of the Milky Way. Discerning between in-situ and ex-situ origin of these objects is difficult when we study the Galactic bulge, which is the most complex and mixed component of the Milky Way. To investigate the early evolution of the Galactic bulge, we analysed the globular cluster NGC 6355. We derived chemical abundances and kinematic and dynamic properties by gathering information from high-resolution spectroscopy with FLAMES-UVES, photometry with the Hubble Space Telescope, and Galactic dynamic calculations applied to the globular cluster NGC 6355. We derive an age of 13.2 +/- 1.1 Gyr and a metallicity of [Fe/H]=- 1.39 +/- 0.08 for NGC 6355, with alpha-enhancement of [alpha/Fe]=; + 0.37 +/- 0.11. The abundance pattern of the globular cluster is compatible with bulge field RR Lyrae stars and in-situ well-studied globular clusters. The orbital parameters suggest that the cluster is currently confined within the bulge volume when we consider a heliocentric distance of 8.54 +/- 0.19 kpc and an extinction coefficient of R-V=2.84 +/- 0.02. NGC 6355 is highly likely to come from the main bulge progenitor. Nevertheless, it still has a low probability of being formed from an accreted event because its age is uncertain and because of the combined [Mg/Mn] [Al/Fe] abundance. Its relatively low metallicity with respect to old and moderately metal-poor inner Galaxy clusters may suggest a low-metallicity floor for globular clusters that formed in-situ in the early Galactic bulge.

引用

页数：21