ATTENZIONE! IL REPOSITORY E’ APERTO ESCLUSIVAMENTE ALL’IMMISSIONE DEI RAPPORTI TECNICI (COLLEZIONE 4.01). NON E’ POSSIBILE INSERIRE PRODOTTI IN TUTTE LE ALTRE COLLEZIONI, A CAUSA DI PROBLEMI TECNICI. THE REPOSITORY IS OPEN EXCLUSIVELY FOR THE SUBMISSION OF TECHNICAL REPORTS (COLLECTION 4.01). SUBMISSIONS TO ALL OTHER COLLECTIONS ARE TEMPORARILY UNAVAILABLE, DUE TO TECHNICAL ISSUES.
 

Extended main-sequence turnoff and red clump in intermediate-age star clusters: A study of NGC 419

Journal
Date Issued
2023
Author(s)
Dresbach, F.
•
•
•
Ferraro, Francesco R.
•
•
•
Raso, S.
DOI
Abstract
With the goal of untangling the origin of extended main-sequence turnoffs (eMSTOs) and extended red clumps (eRCs) in star clusters, in this work we present the study of the intermediate-age cluster NGC 419, situated along the Bridge of the Small Magellanic Cloud. To this aim, we analyzed multi-epoch, high angular resolution observations acquired with the Hubble Space Telescope for this dynamically young cluster, which enabled the determination of precise proper motions and therefore the assessment of the cluster membership for each individual star in the field of view. With this unprecedented information at hand, we first studied the radial distribution of kinematically selected member stars in different eMSTO subregions. The absence of segregation supports the rotation scenario as the cause for the turnoff color extension and disfavors the presence of a prolonged period of star formation in the cluster. A similar analysis on the eRC of NGC 419 confirms the absence of segregation, providing further evidence against an age spread, which is at odds with previous investigations. Even so, the currently available evolutionary models including stellar rotation fail at reproducing the two photometric features simultaneously. We argue that either shortcomings in these models or a different origin for the red clump feature, such as a nonstandard differential mass loss along the red giant branch phase, are the only way to reconcile our observational findings with theoretical expectations.
Volume
679
Start page
A102
Uri
Url
Issn Identifier
0004-6361
Rights
open.access
File(s)
Loading...
Thumbnail Image
Name

Dresbach23.pdf

Size

621.74 KB

Format

Adobe PDF

Checksum (MD5)

b4885cb4e6a1c3de25f618a92cc4b95e

Loading...
Thumbnail Image
Name

aa47405-23.pdf

Description
Pdf editoriale
Size

674.09 KB

Format

Adobe PDF

Checksum (MD5)

9bef031d05c5595f5bdfdad148b87032