Exploring Star Clusters: What Can Age, U-B, B-V, V Data Tell Us?

[randa177]

Hi,
Let's say that you had the following information (age with errors, U-B, B-V, V) for 100 star clusters, what would you do with it? What can it be useful for?
Just wondering...

 

[Matterwave]

Well with the U-B and B-V and V (which implies obviously you know B and U), you can construct HR diagrams. From the HR diagram you can roughly see what type (e.g. red giants, or blue giants, or spectral type) of stars you are observing and from this, get rough age estimates (which I suppose you already had?).

Beyond that, you can make a color-color diagram for U-B vs B-V and see the effects of reddening of the starlight by the ISM by matching your graph to an expected M.S. graph.

Uhm...that's all I can think of for that information.

 

[randa177]

Well with the U-B and B-V and V (which implies obviously you know B and U), you can construct HR diagrams. From the HR diagram you can roughly see what type (e.g. red giants, or blue giants, or spectral type) of stars you are observing and from this, get rough age estimates (which I suppose you already had?).

Beyond that, you can make a color-color diagram for U-B vs B-V and see the effects of reddening of the starlight by the ISM by matching your graph to an expected M.S. graph.

Uhm...that's all I can think of for that information.

Is there any research work one can do with using this info?Like having a published paper?

 

[harcel]

Depends on what kind of star clusters these are? Open clusters in the Milky Way? Globulars? Some extragalactic population?

 

[randa177]

Depends on what kind of star clusters these are? Open clusters in the Milky Way? Globulars? Some extragalactic population?

LMC star clusters.

 

[harcel]

That sounds good :) Any more details on selection criteria for example? What telescope took them?

 

[randa177]

That sounds good :) Any more details on selection criteria for example? What telescope took them?

just got them from literature...

 

[harcel]

Allright. Well, literature might tell you how the clusters were selected then :) 100 does not sound like a very large number for the LMC population, so it might be just the very brightest ones, or all concentrated in one region.

What I would do with it depends completely on what kind of clusters there are. I could think of age gradients through the LMC system itself, differences in subsets of the clusters and their luminosity function, based on location, environment, ... Or, if you have luminosities, colours and ages, then masses are easily determined (and metallicities and extinction should be known to some degree as well), so more physical parameters like the mass function could be determined as well. This might then give some insight in the formation and destruction history of the star clusters in the LMC.

In short: the more details about the cluster population: the easier it is to think of a project to use them for :)