Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 4 of 4
Full-Text Articles in Physical Sciences and Mathematics
The Acs Survey Of Galactic Globular Clusters. Vi. Ngc 6366: A Heavily Stripped Galactic Globular Cluster, Nathaniel E. Q. Paust, Antonio Aparicio, Giampaolo Piotto, I. Neill Reid, Jay Anderson, Ata Sarajedini, Luigi R. Bedin, Brian Chaboyer
The Acs Survey Of Galactic Globular Clusters. Vi. Ngc 6366: A Heavily Stripped Galactic Globular Cluster, Nathaniel E. Q. Paust, Antonio Aparicio, Giampaolo Piotto, I. Neill Reid, Jay Anderson, Ata Sarajedini, Luigi R. Bedin, Brian Chaboyer
Dartmouth Scholarship
We have used observations obtained as part of the Hubble Space Telescope/ACS Survey of Galactic globular clusters (GCs) to construct a color-magnitude diagram for the bulge cluster, NGC 6366. The luminosity function derived from those data extends to M F606W ~ 9, or masses of ~0.3 M ☉. Unlike most GCs, the mass function peaks near the main-sequence turnoff with significantly fewer low-mass stars even after correction for completeness and mass segregation. Using a multimass King model, we extrapolate the global cluster behavior and find the global mass function to be poorly matched by a power law, with …
The Acs Survey Of Galactic Globular Clusters. Iii. The Double Subgiant Branch Of Ngc 1851, A. P. Milone, L. R. Bedin, G. Piotto, J. Anderson, I. R. King, A. Sarajedini, A. Dotter, B. Chaboyer, A. Marin Franch, S. Majewski, A. Aparicio, M. Hempel, N. E.Q Paust, I. N. Reid, A. Rosenberg, M. Siegel
The Acs Survey Of Galactic Globular Clusters. Iii. The Double Subgiant Branch Of Ngc 1851, A. P. Milone, L. R. Bedin, G. Piotto, J. Anderson, I. R. King, A. Sarajedini, A. Dotter, B. Chaboyer, A. Marin Franch, S. Majewski, A. Aparicio, M. Hempel, N. E.Q Paust, I. N. Reid, A. Rosenberg, M. Siegel
Dartmouth Scholarship
Photometry with the Hubble Space Telescope Advanced Camera for Surveys (HST ACS) reveals that the subgiant branch (SGB) of the globular cluster NGC 1851 splits into two well-defined branches. If the split is due only to an age effect, the two SGBs would imply two star formation episodes separated by ~1 Gyr. We discuss other anomalies in NGC 1851 that could be interpreted in terms of a double stellar population. Finally, we compare the case of NGC 1851 with the other two globulars known to host multiple stellar populations, and show that all three clusters differ in several important …
The Dartmouth Stellar Evolution Database, Aaron Dotter, Brian Chaboyer, Darko Jevremović, Veselin Kostov
The Dartmouth Stellar Evolution Database, Aaron Dotter, Brian Chaboyer, Darko Jevremović, Veselin Kostov
Dartmouth Scholarship
The ever-expanding depth and quality of photometric and spectroscopic observations of stellar populations increase the need for theoretical models in regions of age-composition parameter space that are largely unexplored at present. Stellar evolution models that employ the most advanced physics and cover a wide range of compositions are needed to extract the most information from current observations of both resolved and unresolved stellar populations. The Dartmouth Stellar Evolution Database is a collection of stellar evolution tracks and isochrones that spans a range of [Fe/H] from –2.5 to +0.5, [α/Fe] from –0.2 to +0.8 (for [Fe/H] ≤ 0) or +0.2 (for …
Globular Clusters In The Outer Galactic Halo: Am-1 And Palomar 14, Aaron Dotter, Ata Sarajedini, Soung-Chul Yang
Globular Clusters In The Outer Galactic Halo: Am-1 And Palomar 14, Aaron Dotter, Ata Sarajedini, Soung-Chul Yang
Dartmouth Scholarship
AM-1, at ~120 kpc, and Palomar 14 (Pal 14), at ~70 kpc, are two of the most distant Galactic globular clusters (GCs) known. We present Hubble Space Telescope Wide Field Planetary Camera 2 photometry of AM-1 and Pal 14 that reveals unprecedented depth and detail in the color-magnitude diagrams of these two clusters. Absolute and relative age measurements confirm that both are younger than the inner halo GC M 3 by 1.5-2 Gyr assuming all three clusters have similar compositions. Thus AM-1 and Pal 14 join Pal 3, Pal 4, and Eridanus as distant GCs with red horizontal branches (HBs) …