Constarium
← Search

Table · dataset · 2015

Parameters of galactic globular clusters

Listed in IVOA Registry (Virtual Observatory)

We use our Galactic Globular Cluster Catalog (G2C2) photometry for 111 Galactic globular clusters (GCs) in g and z, as well as r and i photometry for a subset of 60 GCs and u photometry for 22 GCs, to determine the structural parameters assuming King models.

Description

In general, the resulting core radii are in good comparison with the current literature values. However, our half-light radii are slightly lower than the literature.

The concentrations (and therefore also the tidal radii) are poorly constrained mostly because of the limited radial extent of our imaging. Therefore, we extensively discuss the effects of a limited field of view on the derived parameters using mosaicked Sloan Digital Sky Survey data, which do not suffer from this restriction. We also illustrate how red giant branch (RGB) stars in cluster cores can stochastically induce artificial peaks in the surface brightness profiles.

Read the rest (2 more)

The issues related to these bright stars are scrutinized based on both our photometry and simulated clusters. We also examine colour gradients and find that the strongest central colour gradients are caused by central RGB stars and thus not representative for the cluster light or colour distribution. We recover the known relation between the half-light radius and the Galactocentric distance in the g band, but find a lower slope for redder filters.

We did not find a correlation between the scatter on this relation and other cluster properties. We find tentative evidence for a correlation between the half-light radii and the [Fe/H], with metal-poor GCs being larger than metal-rich GCs. However, we conclude that this trend is caused by the position of the clusters in the Galaxy, with metal-rich clusters being more centrally located.

Links

Topics

Stated by source
Optical
Inferred from text
Astronomical sciences 74% · Imaging 75%
Provenance · 1 source records, 10 field assertions
SourceKeyLast seenRaw
IVOA Registry (Virtual Observatory)ivo://cds.vizier/j/mnras/450/269213 d agoJSON v1
FieldAssertionExtractorEvidence
access_levelsource · IVOA Registryconnector:ivoa_registry@1.0.0
concepts[field].anzsrc:group:5101enrichment · IVOA Registrytaxonomy-embedding@1.1.0title+keywords+description (74%)
concepts[field].local:field:astronomymapping · IVOA Registryconnector:ivoa_registry@1.0.0
concepts[modality].ivoa_waveband:opticalsource · IVOA Registryconnector:ivoa_registry@1.0.0
concepts[modality].local:modality:imagingenrichment · IVOA Registrykeyword-concept-rules@1.0.0title+description (75%)
descriptionsource · IVOA Registryconnector:ivoa_registry@1.0.0rr.resource.res_description
license_textsource · IVOA Registryconnector:ivoa_registry@1.0.0
publication_datesource · IVOA Registryconnector:ivoa_registry@1.0.0
titlesource · IVOA Registryconnector:ivoa_registry@1.0.0rr.resource.res_title
updated_datesource · IVOA Registryconnector:ivoa_registry@1.0.0