期刊
ASTROPHYSICAL JOURNAL
卷 860, 期 1, 页码 -出版社
IOP PUBLISHING LTD
DOI: 10.3847/1538-4357/aac16b
关键词
galaxies: dwarf; galaxies: photometry; galaxies: structure; globular clusters: general; Local Group; surveys
资金
- project BASAL [PFB-06]
- FONDECYT [1170364]
- National Science Foundation [AST-0908752]
- Alfred P. Sloan Foundation
- NSF [AST-1313422, AST-1413600, AST-1518308]
- Ajax Foundation
We present structural parameters from a wide-field homogeneous imaging survey of Milky Way satellites carried out with the MegaCam imagers on the 3.6 m Canada-France-Hawaii Telescope and 6.5 m Magellan-Clay telescope. Our survey targets an unbiased sample of outer halo satellites (i.e., substructures having galactocentric distances greater than 25 kpc) and includes classical dSph galaxies, ultra-faint dwarfs, and remote globular clusters. We combine deep, panoramic gr imaging for 44 satellites and archival gr imaging for 14 additional objects (primarily obtained with the DECam instrument as part of the Dark Energy Survey) to measure photometric and structural parameters for 58 outer halo satellites. This is the largest and most uniform analysis of Milky Way satellites undertaken to date and represents roughly three-quarters (58/81 similar or equal to 72%) of all known outer halo satellites. We use a maximum-likelihood method to fit four density laws to each object in our survey: exponential, Plummer, King, and Sersic models. We systematically examine the isodensity contour maps and color-magnitude diagrams for each of our program objects, present a comparison with previous results, and tabulate our best-fit photometric and structural parameters, including ellipticities, position angles, effective radii, Sersic indices, absolute magnitudes, and surface brightness measurements. We investigate the distribution of outer halo satellites in the size-magnitude diagram and show that the current sample of outer halo substructures spans a wide range in effective radius, luminosity, and surface brightness, with little evidence for a clean separation into star cluster and galaxy populations at the faintest luminosities and surface brightnesses.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据