A How Can I Filter Known Globular Clusters in SDSS Data?

AI Thread Summary
Searching for globular clusters (GCs) in SDSS data reveals a lack of direct identifiers for these clusters, as nearby ones are cataloged as individual stars and distant ones as galaxies. Users are struggling to filter known GCs based on specific conditions due to this absence of clear data flags. The SDSS documentation indicates that while globular clusters are present, the photometric pipeline may struggle with the crowded regions around them. Additionally, resources and studies related to GCs in SDSS are available, suggesting potential avenues for further inquiry. Contacting authors of relevant studies may provide insights into their methods for identifying and processing GC data.
mancini
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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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