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

• 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 (similar to 10(5) M-circle dot, similar to 1.4 Gyr). Unlike previous studies, here we focus on stars in the same mass range found in old globulars (similar to 0.75-1 M-circle dot), 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.

Subject headings

NATURVETENSKAP  -- Fysik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences (hsv//eng)

Keyword

stars: abundances

Hertzsprung-Russell and colour-magnitude diagrams

globular clusters: general

globular clusters: individual: NGC 419

47 Tuc

NGC 6352

NGC 6637

galaxies: individual: SMC

Milky Way

Publication and Content Type

ref (subject category)

art (subject category)