Long term CCD photometry of the distant cluster NGC 2419: the CMD revisited

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Ferro, A. Arellano, Muneer, S., Giridhar, Sunetra, Fierro, I. Bustos, Yepez, M. A., Pérez, G. A. García, Segura, G. Rios
Natura: Preprint
Pubblicazione: 2024
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866913335839031296
author Ferro, A. Arellano
Muneer, S.
Giridhar, Sunetra
Fierro, I. Bustos
Yepez, M. A.
Pérez, G. A. García
Segura, G. Rios
author_facet Ferro, A. Arellano
Muneer, S.
Giridhar, Sunetra
Fierro, I. Bustos
Yepez, M. A.
Pérez, G. A. García
Segura, G. Rios
contents Employing \emph{VI} images of NGC 2419 acquired over 17 years, light curves for most of the known variables in the field of the cluster are produced. A cluster membership analysis for about 3100 stars in the cluster field with proper motions from $Gaia$-DR3, revealed the presence of member stars as far as 140 pc from the cluster center and enabled the construction of a cleaner CMD free of field stars. It was found that RRab and RRc stars share the inter-order region in the instability strip, which is unusual for OoII clusters. Theoretical considerations confirm that Pop II cepheids are descendants of extreme ZAHB blue tail stars with very thin envelopes of about 10\% of the total mass. Member RR Lyrae stars were employed to calculate independent estimates of the mean cluster metallicity and distance; we found [Fe/H]$_{\rm UV}= -1.90 \pm 0.27$ and $D=86.3 \pm 5.0$ kpc from the RRab and [Fe/H]$_{\rm UV}= -1.88 \pm 0.30$ and $D=83.1 \pm 8.1$ kpc from the RRc light curves.
format Preprint
id arxiv_https___arxiv_org_abs_2404_19151
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Long term CCD photometry of the distant cluster NGC 2419: the CMD revisited
Ferro, A. Arellano
Muneer, S.
Giridhar, Sunetra
Fierro, I. Bustos
Yepez, M. A.
Pérez, G. A. García
Segura, G. Rios
Solar and Stellar Astrophysics
Astrophysics of Galaxies
Employing \emph{VI} images of NGC 2419 acquired over 17 years, light curves for most of the known variables in the field of the cluster are produced. A cluster membership analysis for about 3100 stars in the cluster field with proper motions from $Gaia$-DR3, revealed the presence of member stars as far as 140 pc from the cluster center and enabled the construction of a cleaner CMD free of field stars. It was found that RRab and RRc stars share the inter-order region in the instability strip, which is unusual for OoII clusters. Theoretical considerations confirm that Pop II cepheids are descendants of extreme ZAHB blue tail stars with very thin envelopes of about 10\% of the total mass. Member RR Lyrae stars were employed to calculate independent estimates of the mean cluster metallicity and distance; we found [Fe/H]$_{\rm UV}= -1.90 \pm 0.27$ and $D=86.3 \pm 5.0$ kpc from the RRab and [Fe/H]$_{\rm UV}= -1.88 \pm 0.30$ and $D=83.1 \pm 8.1$ kpc from the RRc light curves.
title Long term CCD photometry of the distant cluster NGC 2419: the CMD revisited
topic Solar and Stellar Astrophysics
Astrophysics of Galaxies
url https://arxiv.org/abs/2404.19151