1 / 17

Galactic Globular Clusters in SDSS

Galactic Globular Clusters in SDSS. Eunhyeuk Kim SNU Astronomy 2008. 2. 18. SDSS Workshop at High One ski Resort. Motivation. Construct a set of CMDs of galactic globular clusters in SDSS gri filter system.

luka
Download Presentation

Galactic Globular Clusters in SDSS

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Galactic Globular Clusters in SDSS Eunhyeuk Kim SNU Astronomy 2008. 2. 18. SDSS Workshop at High One ski Resort

  2. Motivation • Construct a set of CMDs of galactic globular clusters in SDSS gri filter system. • Take the advantage of wide field of view of SDSS observation: Tidal tails of GCs • Investigate the relic of the initial angular momentum in globular clusters by inspecting their mass/luminosity function.

  3. SDSS Observations of GGCs • SDSS DR6 covers ~1/4 of full sky. • Expected to observe ~ dozens of galactic globular clusters (GGCs). • Due to high concentration of GGCs in MW bulge and southern hemisphere, only 16 out of ~150 GGCs are observed in SDSS (mostly metal-poor systems).

  4. Location of GGCs in MW

  5. NGC6205 (M13) NGC6341 (M92) 1deg 1deg

  6. SDSS Catalog of GGC (M3) 1. Pipeline time limit in dealing with a single object: crowded fields of stars are remained to be blank in the SDSS catalog. 2. Pipeline is not optimized for stellar photometry. 3. Keep consistency in photometry. We need a fast and reliable tool for stellar photometry.

  7. New Stellar Photometry • DoPHOT version optimized to deal with SDSS images (Smolcic, 2007). • Post photometry procedure is prepared by SNU Observational Cosmology Team : SDSS-DoPHOT • Is very easy to use ( < 1 hour of education) and is extremely fast to obtain a photometry.

  8. SDSS vs. SDSS-DoPHOT Sum of 16 galactic globular clusters observed in SDSS. • <70% for a half of tidal radius • ~5-20% of stars are missing for the outer region of GCs New photometry using SDSS-DoPHOT is highly recommended for the stellar photometry of crowded fields.

  9. CMDs of SDSS GGCs

  10. Tidal Tails • A stellar system orbiting its host galaxy eventually experiences a directional loss of its contents through combined dynamical processes of evaporation and tidal stripping by the host galaxy. • We can trace the history of the dynamical evolution of GC and host galaxy by investigating the shape of the tidal tails.

  11. Tidal Tails: member selection

  12. Tidal Tails : 1D density profiles Possible Detection of tidal tails of M5, M13, M92, M15

  13. Tidal Tails : 2D structures

  14. Tidal Tails : 2D structures

More Related