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Globular Clusters: From the Nearest to the Most Distant. April 03, 2007. Hubble Fellows Symposium - STScI. Jason Kalirai (UC Santa Cruz). The NGC 6397 Group: Rice - Jay Anderson UBC - Harvey B. Richer, James P. Brewer, Saul D. Davis UWashington - Ivan King
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Globular Clusters: From the Nearest to the Most Distant April 03, 2007 Hubble Fellows Symposium - STScI Jason Kalirai (UC Santa Cruz) The NGC 6397 Group: Rice - Jay Anderson UBC - Harvey B. Richer, James P. Brewer, Saul D. Davis UWashington - Ivan King UCLA - Brad M. S. Hansen, R. Michael Rich, David B. Reitzel Universidad de Chile - Giovanni Carraro HIA/NRC - Gregory G. Fahlman, Peter B. Stetson AMNH - Sebastien Lepine, Michael M. Shara Swinburne - Jarrod R. Hurley
Globular Clusters: From the Nearest to the Most Distant April 03, 2007 Hubble Fellows Symposium - STScI A FEW Reasons to Study Star Clusters: Structure formation. Properties of distant galaxies. Stellar evolution. Harris 1996, AJ, 112, 1487 Buonanno et al. 1994, A&A, 290, 69
Globular Clusters: From the Nearest to the Most Distant Dude….what the heck is a white dwarf? April 03, 2007 Hubble Fellows Symposium - STScI Primary Goals: Measure the ages of nearby globular clusters using white dwarf cooling theory.
Globular Clusters: From the Nearest to the Most Distant April 03, 2007 Hubble Fellows Symposium - STScI White Dwarf Cosmochronology
Globular Clusters: From the Nearest to the Most Distant April 03, 2007 Hubble Fellows Symposium - STScI Primary Goals: Measure the ages of nearby globular clusters using white dwarf cooling theory. 1st study - Messier 4 - 123 orbits of HST/WFPC2 awarded in Cycle 11. 2nd study - NGC 6397 - 126 orbits of HST/ACS awarded in Cycle 13. 3rd study - 47 Tuc?
Globular Clusters: From the Nearest to the Most Distant April 03, 2007 Hubble Fellows Symposium - STScI Primary Goals: Measure the ages of nearby globular clusters using white dwarf cooling theory. 1st study - Messier 4 - 123 orbits of HST/WFPC2 awarded in Cycle 11. 2nd study - NGC 6397 - 126 orbits of HST/ACS awarded in Cycle 13. 3rd study - 47 Tuc? A clean study of the main-sequence stars: MLR, LF/MF, constrain evolutionary models.
Globular Clusters: From the Nearest to the Most Distant April 03, 2007 Hubble Fellows Symposium - STScI Proper Motions Kalirai et al. 2007, ApJL, 657, 93
Globular Clusters: From the Nearest to the Most Distant April 03, 2007 Hubble Fellows Symposium - STScI Primary Goals: Measure the ages of nearby globular clusters using white dwarf cooling theory. 1st study - Messier 4 - 123 orbits of HST/WFPC2 awarded in Cycle 11. 2nd study - NGC 6397 - 126 orbits of HST/ACS awarded in Cycle 13. 3rd study - 47 Tuc? A clean study of the main-sequence stars: MLR, LF/MF, constrain evolutionary models. Link picture from stellar evolution with dynamical evolution (internal/external). Extra: Globular Clusters in a Globular Cluster!
Globular Clusters: From the Nearest to the Most Distant = +3.56 +/- 0.04 mas/yr = -17.34 +/- 0.04 mas/yr Kalirai et al. 2007, ApJL, 657, 93 April 03, 2007 Hubble Fellows Symposium - STScI The Orbit of NGC 6397
Globular Clusters: From the Nearest to the Most Distant April 03, 2007 Hubble Fellows Symposium - STScI Richer et al. (2006, Science, 313, 936)
Globular Clusters: From the Nearest to the Most Distant April 03, 2007 Hubble Fellows Symposium - STScI The White Dwarf Cooling Age of NGC 6397: Hansen et al. (2007, ApJ submitted, astro-ph/0701738)
Globular Clusters: From the Nearest to the Most Distant April 03, 2007 Hubble Fellows Symposium - STScI Age = 11.47 +/- 0.47 Gyr Hansen et al. (2007, ApJ submitted, astro-ph/0701738)
Globular Clusters: From the Nearest to the Most Distant April 03, 2007 Hubble Fellows Symposium - STScI
Globular Clusters: From the Nearest to the Most Distant April 03, 2007 Hubble Fellows Symposium - STScI Kalirai, Strader, et al. 2007, ApJ, in prep.
Globular Clusters: From the Nearest to the Most Distant April 03, 2007 Hubble Fellows Symposium - STScI Summary: White dwarf cooling age of NGC 6397 = 11.47 +/- 0.47 Gyr. Cluster orbit suggests frequent interactions with bulge/disk. Proper motion cleaned study of low mass cluster mass function. z = 0.1 extragalactic globular cluster system found. CMD of 245 globulars NGC 6397 ---- 1 Extragal. ---- 244
Image Credit: NASA and The Hubble Heritage Team (STScI/AURA) - Hubble Space Telescope WFPC2 - STScI-PRC03-21