Globular clusters in SDSS data

In summary, after searching through SDSS data and documentation, it appears that there is no direct identifier for globular clusters (GCs). Nearby clusters are catalogued as individual stars with no apparent link to a parent cluster ID or name, while far away clusters are catalogued as galaxies. There is no data flag that allows for filtering out known GCs based on certain conditions. However, there have been some studies using SDSS data to identify GCs, and it may be helpful to contact the authors of these studies for more information on how they identified and processed the GC data.
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Haven't found any data flag that would enable me to search for GCs in SDSS data. What am I missing?
I am searching for Globular Clusters in SDSS data. From what I have learned after sifting through documentation and the data structures, there is no identifier by which I could directly search for GCs.

Nearby clusters are catalogued as individual stars with no apparent link to parent cluster id/bname or anything that I found useful.

Far away clusters are catalogued as galaxies (logical, they are extended objects) but can't find anything else.

Is there a way to filter out all known GCs that fit certain conditions? What am I missing?

Thank you vary much for any help,
Michal
 
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mancini said:
Summary:: Haven't found any data flag that would enable me to search for GCs in SDSS data. What am I missing?

Is there a way to filter out all known GCs that fit certain conditions? What am I missing?

I looked at the SDSS site and found the following statement:
All of the clusters seen by the SDSS are globular clusters, thick clusters containing millions of stars that lie just above and just below the plan (sic) of our galaxy. The two clusters we'll work with were both found by the Palomar Sky Survey in the 1950's, hence the names Pal 3 and Pal 5. Their coordinates are given below.
https://skyserver.sdss.org/dr1/en/proj/advanced/hr/globularcluster.asp

https://arxiv.org/abs/0808.0001 - "While star clusters provide important calibration samples for stellar colors, the regions close to globular clusters, where the fraction of field stars is smallest, are too crowded for the standard SDSS photometric pipeline to process."

https://arxiv.org/abs/1010.4697 - Mining SDSS in search of Multiple Populations in Globular Clusters

GLOBULAR AND OPEN CLUSTERS OBSERVED BY SDSS/SEGUE: THE GIANT STARS
https://iopscience.iop.org/article/10.3847/0004-6256/151/1/7

https://repositories.lib.utexas.edu/handle/2152/43115

Perhaps one can contact the authors and ask how they identified/processed the GC data in SDSS.
 
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1. What are globular clusters?

Globular clusters are dense, spherical clusters of stars that are found in the outer regions of galaxies. They typically contain hundreds of thousands to millions of stars that are tightly bound together by gravity.

2. How are globular clusters identified in SDSS data?

Globular clusters are identified in SDSS data through a combination of color and brightness measurements. These clusters are typically very old and have a distinct color and brightness pattern that allows them to be distinguished from other objects in the data.

3. What can we learn from studying globular clusters in SDSS data?

By studying globular clusters in SDSS data, we can learn about the formation and evolution of galaxies. These clusters are thought to be some of the oldest structures in the universe, providing a glimpse into the early stages of galaxy formation.

4. How do globular clusters contribute to our understanding of dark matter?

Globular clusters are important in studying dark matter because they can be used as gravitational lenses. This means that they can bend and distort light from more distant objects, allowing us to indirectly detect the presence of dark matter in these clusters.

5. Are there any specific globular clusters that have been studied in SDSS data?

Yes, there have been several globular clusters that have been studied in SDSS data, including Omega Centauri, 47 Tucanae, and M15. These clusters have provided valuable insights into their formation and evolution, as well as the properties of the galaxies they are found in.

Suggested for: Globular clusters in SDSS data

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