Change search
ReferencesLink to record
Permanent link

Direct link
The effect of spatial resolution on optical and near-IR studies of stellar clusters: implications for the origin of the red excess
Stockholm University, Faculty of Science, Department of Astronomy. Max Planck Institut für Astronomie, Germany.
Show others and affiliations
2014 (English)In: Monthly notices of the Royal Astronomical Society, ISSN 0035-8711, E-ISSN 1365-2966, Vol. 444, no 4, 3829-3836 p.Article in journal (Refereed) Published
Abstract [en]

Recent ground-based near-IR (NIR) studies of stellar clusters in nearby galaxies have suggested that young clusters remain embedded for 7-10 Myr in their progenitor molecular cloud, in conflict with optical-based studies which find that clusters are exposed after 1-3 Myr. Here, we investigate the role that spatial resolution plays in this apparent conflict. We use a recent catalogue of young (< 10 Myr) massive (> 5000M(circle dot)) clusters in the nearby spiral galaxy, M83, along with Hubble Space Telescope (HST) imaging in the optical and NIR, and ground-based NIR imaging, to see how the colours (and hence estimated properties such as age and extinction) are affected by the aperture size employed, in order to simulate studies of differing resolution. We find that the NIR is heavily affected by the resolution, and when aperture sizes > 40 pc are used, all young/blue clusters move redwards in colour space, which results in their appearance as heavily extincted clusters. However, this is due to contamination from nearby sources and nebular emission, and is not an extinction effect. Optical colours are much less affected by resolution. Due to the larger effect of contamination in the NIR, we find that, in some cases, clusters will appear to show NIR excess when large (> 20 pc) apertures are used. Our results explain why few young (< 6 Myr), low-extinction (AV < 1 mag) clusters have been found in recent ground-based NIR studies of cluster populations, while many such clusters have been found in higher resolution HST-based studies. Additionally, resolution effects appear to (at least partially) explain the origin of the NIR excess that has been found in a number of extragalactic young massive clusters.

Place, publisher, year, edition, pages
2014. Vol. 444, no 4, 3829-3836 p.
Keyword [en]
ISM: bubbles, H II regions, galaxies: star clusters
National Category
Astronomy, Astrophysics and Cosmology
URN: urn:nbn:se:su:diva-109799DOI: 10.1093/mnras/stu1695ISI: 000343400100062OAI: diva2:778188


Available from: 2015-01-09 Created: 2014-12-01 Last updated: 2015-01-09Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full text

Search in DiVA

By author/editor
Adamo, Angela
By organisation
Department of Astronomy
In the same journal
Monthly notices of the Royal Astronomical Society
Astronomy, Astrophysics and Cosmology

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 26 hits
ReferencesLink to record
Permanent link

Direct link