A MegaCam Survey of Outer Halo Satellites. I. Description of the Survey
A MegaCam Survey of Outer Halo Satellites. I. Description of the Survey
复制标题
外晕卫星的 MegaCam 勘测。
DOI：
10.3847/1538-4357/aac168
复制
发表时间：
2018
期刊：
影响因子：
--
通讯作者：
S. Djorgovski
中科院分区：
文献类型：
--
作者：
R. Muñoz;R. Muñoz;P. Côté;F. Santana;M. Geha;J. Simon;Grecco A. Oyarzún;P. Stetson;S. Djorgovski
我们描述了对银河系外晕卫星的深入、系统的成像研究。我们的样本由 58 个恒星超密度组成，即分类为球状星团、经典矮星系或超微弱矮星系的子结构，这些子结构位于 RGC ≥ 25 kpc（外晕）和~400 kpc 的星系中心距离处。其中包括 44 个物体，我们使用 3.6 m 加拿大-法国-夏威夷望远镜和 6.5 m 麦哲伦-克莱望远镜上的 MegaCam 马赛克相机获取了深部、宽视场、g 和 r 波段成像。这些数据由另外 14 个天体的档案成像或已发表的 gr 光度测定法进行补充，其中大多数是最近在暗能量巡天 (DES) 中发现的。我们描述了我们调查的科学动机，包括样本选择、观测策略、数据缩减管道、校准程序以及光度测定的深度和精度。 MegaCam 成像的典型 5σ 点源极限星等（总共覆盖约 52 deg2 的区域）为 glim ≃ 25.6 和 rlim ≃ 25.3 AB mag。这些限制与叠加的 DES 图像的限制相当，并且比使用大型综合巡天望远镜单次访问所达到的限制深大约半倍。因此，我们的光度目录提供了在可预见的未来最深入、最统一的银河系卫星光度数据库。在本系列的其他论文中，我们使用这些数据来探索这些天体中的蓝离散星群、它们的密度分布、恒星形成历史、尺度关系和可能的前景结构。
We describe a deep, systematic imaging study of satellites in the outer halo of the Milky Way. Our sample consists of 58 stellar overdensities—i.e., substructures classified as either globular clusters, classical dwarf galaxies, or ultra-faint dwarf galaxies—that are located at Galactocentric distances of RGC ≥ 25 kpc (outer halo) and out to ∼400 kpc. This includes 44 objects for which we have acquired deep, wide-field, g- and r-band imaging with the MegaCam mosaic cameras on the 3.6 m Canada–France–Hawaii Telescope and the 6.5 m Magellan-Clay telescope. These data are supplemented by archival imaging, or published gr photometry, for an additional 14 objects, most of which were discovered recently in the Dark Energy Survey (DES). We describe the scientific motivation for our survey, including sample selection, observing strategy, data reduction pipeline, calibration procedures, and the depth and precision of the photometry. The typical 5σ point-source limiting magnitudes for our MegaCam imaging—which collectively covers an area of ≈52 deg2—are glim ≃ 25.6 and rlim ≃ 25.3 AB mag. These limits are comparable to those from the coadded DES images and are roughly a half-magnitude deeper than will be reached in a single visit with the Large Synoptic Survey Telescope. Our photometric catalog thus provides the deepest and most uniform photometric database of Milky Way satellites available for the foreseeable future. In other papers in this series, we have used these data to explore the blue straggler populations in these objects, their density distributions, star formation histories, scaling relations, and possible foreground structures.
影响因子：
4.8
作者：
V. Belokurov;M. Irwin;Sergey E. Koposov;N. Evans;E. González-Solares;N. Metcalfe;T. Shanks
通讯作者：
V. Belokurov;M. Irwin;Sergey E. Koposov;N. Evans;E. González-Solares;N. Metcalfe;T. Shanks
DOI：
10.1088/2041-8205/712/1/l103
发表时间：
2010-02
期刊：
The Astrophysical Journal Letters
影响因子：
--
作者：
V. Belokurov;M. Walker;N. Evans;G. Gilmore;M. Irwin;D. Just;Sergey E. Koposov;M. Mateo;E. Olszewski;L. Watkins;L. W. IoA;Cambridge;S. Observatory;Tucson;U. Michigan
通讯作者：
V. Belokurov;M. Walker;N. Evans;G. Gilmore;M. Irwin;D. Just;Sergey E. Koposov;M. Mateo;E. Olszewski;L. Watkins;L. W. IoA;Cambridge;S. Observatory;Tucson;U. Michigan