When Does the Onset of Multiple Stellar Populations in Star Clusters Occur? III. No Evidence of Significant Chemical Variations in Main-sequence Stars of NGC 419

Li, Chengyuan; Wang, Yue; Tang, Baitian; Milone, A. P.; Yang, Yujiao; X, Ji

doi:10.3847/1538-4357/ab7b64

Cited by 19 publications

(9 citation statements)

References 49 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We note thatLi et al (2020) came to similar conclusions with the same data set in a paper that appeared after the submission of this paper. In summary, they fitted synthetic clusters with different degrees of N abundance variations to the observations of low-mass MS stars of NGC 419.…”

supporting

confidence: 74%

Searching for globular cluster chemical anomalies on the main sequence of a young massive cluster

Cabrera-Ziri

Speagle

Dalessandro³

et al. 2020

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

The spectroscopic and photometric signals of the star-to-star abundance variations found in globular clusters seem to be correlated with global parameters like the cluster’s metallicity, mass, and age. Understanding this behaviour could bring us closer to the origin of these intriguing abundance spreads. In this work we use deep HST photometry to look for evidence of abundance variations in the main sequence of a young massive cluster NGC 419 (∼105 M⊙, ∼1.4 Gyr). Unlike previous studies, here we focus on stars in the same mass range found in old globulars (∼0.75–1 M⊙), where light elements variations are detected. We find no evidence for N abundance variations among these stars in the Un − B and U − B colour–magnitude diagrams of NGC 419. This is at odds with the N variations found in old globulars like 47 Tuc, NGC 6352, and NGC 6637 with similar metallicity to NGC 419. Although the signature of the abundance variations characteristic of old globulars appears to be significantly smaller or absent in this young cluster, we cannot conclude if this effect is mainly driven by its age or its mass.

show abstract

supporting

confidence: 74%

Searching for globular cluster chemical anomalies on the main sequence of a young massive cluster

Cabrera-Ziri

Speagle

Dalessandro³

et al. 2020

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

show abstract

“…However, NGC 419 (e.g. Martocchia et al 2017;Li et al 2020), NGC 1806 (Mucciarelli et al 2014) and NGC 1783 (Zhang et al 2018) were found to be consistent with SSPs clusters. The fact that these clusters likely had similar initial masses and that MPs have not been found in young massive clusters (YMCs) (Cabrera-Ziri et al 2016), led several authors to argue that cluster age may also be an indicator of the presence of MPs within clusters and that only clusters older than ∼ 2 Gyr show evidences of MPs (Li & de Grijs 2019;Martocchia et al 2019Martocchia et al , 2021.…”

Section: Global Parameters and The Onset Of Mpsmentioning

confidence: 85%

On the formation of globular clusters: comparison with observations

Jiménez,

Tenorio-Tagle,

Silich

2022

Preprint

View full text Add to dashboard Cite

The paper deals with the conditions required to form at least two stellar generations in globular clusters under the constraints generated by feedback from massive stars as well as radiative cooling and the metallicity of the primordial clouds. Our calculations are based on two main constraints to the star formation efficiency of the first stellar generation (1G) ǫ 1G . First, ǫ 1G is restricted to warrant that stellar winds and supernovae do not disrupt the leftover gas out of which a second generation (2G) would form. Second, ǫ 1G is also limited such that the metallicity enhancement caused by trapped supernovae is, in agreement with the observations, not larger than ∼ 0.1 dex. Several central parameters define the globular clusters end result: the mass and radius of the primordial clouds, their metallicity and ǫ 1G . The parameter space composed by models which fulfilled all constraints, is here shown to coincide remarkably well with the scattered observed anti-correlation between the fraction of first generation stars (f 1G ) and total cluster mass. Our models also discern, in agreement with the data, between single and multiple population clusters in a metallicity versus mass (or radius) plane. Hence, our results suggest that the presence of multiple stellar populations is closely linked to the ability of proto-globular clusters to retain a fraction of leftover gas.

show abstract

“…However, this conclusion is also challenged by e.g. NGC 419 (Li et al 2020) which is a massive cluster but with no apparent signs of MSPs.…”

Section: Introductionmentioning

confidence: 99%

MOCCA: Dynamics and evolution of binary stars of multiple stellar populations in tidally filling and underfilling globular star clusters

Hypki¹,

Giersz²,

Leveque³

et al. 2022

Preprint

View full text Add to dashboard Cite

We present a new upgraded version of the code for the study of dynamical evolution of globular clusters and its first application to the study of evolution of multiple stellar populations. We explore a range of initial conditions spanning different structural parameters for the first (FG) and second population (SG) and we analyze their effect on the binary dynamics and survival. The set of simulations shown here represents the first phase of the new --2 project which will be further extended. Here, we focus our attention on the number ratio of FG and SG binaries, its variation with the distance from the cluster center, and the way their abundances are affected by various cluster initial properties. We find that SG stars more abundant in clusters that were initially tidally filling. Conversely, FG stars stay more abundant in clusters that were initially tidally underfilling. We also find that the ratio between binary fractions is not affected by the way we calculate these fractions (e.g. with the use of all binaries, only main-sequence binaries or observational binaries, i.e. main-sequence stars > 0.4𝑀 , mass ratios > 0.5). We find also that the evolution of mixing between populations presents the same features even if we take into account all single stars too. This implies that the main-sequence stars themselves are a very good proxy for probing entire populations of FG and SG in star clusters.We also discuss how our findings relate to the observations of Milky Way GCs. We show that with MOCCA models we are able to reproduce the observed range of SG fractions for any Milky Way GC for which we know this fraction. We show how the SG fractions depend on the initial conditions. We provide also an explanation what could be the initial conditions of star clusters, which at the Hubble time, have more numerous FG, and which more numerous SG stars.

show abstract

When Does the Onset of Multiple Stellar Populations in Star Clusters Occur? III. No Evidence of Significant Chemical Variations in Main-sequence Stars of NGC 419

Cited by 19 publications

References 49 publications

Searching for globular cluster chemical anomalies on the main sequence of a young massive cluster

Searching for globular cluster chemical anomalies on the main sequence of a young massive cluster

On the formation of globular clusters: comparison with observations

MOCCA: Dynamics and evolution of binary stars of multiple stellar populations in tidally filling and underfilling globular star clusters

Contact Info

Product

Resources

About