The stellar contents of the open clusters King 12, NGC 7788, and NGC 7790 are investigated using MegaCam images. Comparisons with isochrones yield an age < 20 Myr for King 12, 20--40 Myr for NGC 7788, and 60 -- 80 Myr for NGC 7790 based on the properties of stars near the main sequence turn-off (MSTO) in each cluster. The reddening of NGC 7788 is much larger than previously estimated. The luminosity functions (LFs) of King 12 and NGC 7788 show breaks that are attributed to the onset of pre-main sequence ( ...
Tópico(s): Astronomy and Astrophysical Research
2012 - IOP Publishing | The Astrophysical Journal
Christina Blom, Duncan A. Forbes, Jean P. Brodie, Caroline Foster, Aaron J. Romanowsky, Lee R. Spitler, Jay Strader,
We present a kinematic analysis of the globular cluster (GC) system of the giant elliptical galaxy NGC 4365 and find several distinct kinematic substructures. This analysis is carried out using radial velocities for 269 GCs, obtained with the DEIMOS instrument on the Keck II telescope as part of the SAGES Legacy Unifying Globulars and Galaxies Survey (SLUGGS). We find that each of the three (formerly identified) GC colour subpopulations reveal distinct rotation properties. The rotation of the green ...
Tópico(s): Astronomy and Astrophysical Research
2012 - Oxford University Press | Monthly Notices of the Royal Astronomical Society
S. Kaspi, W. N. Brandt, I. M. George, H. Netzer, D. M. Crenshaw, J. R. Gabel, Frederick Hamann, M. E. Kaiser, Anuradha Koratkar, S. B. Kraemer, G. A. Kriss, Smita Mathur, R. F. Mushotzky, K. Nandra, B. M. Peterson, Joseph C. Shields, T. J. Turner, Wei Zheng,
... We resolve the narrow Fe Kα line at 6398.2 ± 3.3 eV to have an FWHM ...
Tópico(s): Astrophysics and Cosmic Phenomena
2002 - IOP Publishing | The Astrophysical Journal
H. R. Dickel, H. J. Habing, R. Isaacman,
Tópico(s): Astronomy and Astrophysical Research
1980 - IOP Publishing | The Astrophysical Journal