Blanco DECam Bulge Survey (BDBS) II: Project Performance, Data Analysis, and Early Science Results
Christian I. Johnson, R. Michael Rich, Michael D. Young, Iulia T. Simion, William I. Clarkson, Catherine A. Pilachowski, Scott Michael, Andrea Kunder, Andreas K… 展开作者
Christian I. Johnson, R. Michael Rich, Michael D. Young, Iulia T. Simion, William I. Clarkson, Catherine A. Pilachowski, Scott Michael, Andrea Kunder, Andreas Koch, A. Katherina Vivas
The Blanco DECam Bulge Survey (BDBS) imaged more than 200 square degrees of the Southern Galactic bulge using the ugrizY filters of the Dark Energy Camera, and produced point spread function photometry of approximately 250 million unique sources. In this paper, we present details regarding the construction and collation of survey catalogs, and also discuss the adopted calibration and dereddening procedures. Early science results are presented with a particular emphasis on the bulge metallicity distribution function and globular clusters. A key result is the strong correlation (sigma ~ 0.2 dex) between (u-i)o and [Fe/H] for bulge red clump giants. We utilized this relation to find that interior bulge fields may be well described by simple closed box enrichment models, but fields exterior to b ~ -6 degrees seem to require a secondary metal-poor component. Applying scaled versions of the closed box model to the outer bulge fields is shown to significantly reduce the strengths of any additional metal-poor components when compared to Gaussian mixture models. Additional results include: a confirmation that the u-band splits the sub-giant branch in M 22 as a function of metallicity, the detection of possible extra-tidal stars along the orbits of M 22 and FSR 1758, and additional evidence that NGC 6569 may have a small but discrete He spread, as evidenced by red clump luminosity variations in the reddest bands. We do not confirm previous claims that FSR 1758 is part of a larger extended structure.
The Blanco DECam Bulge Survey (BDBS) VIII: Chemo-kinematics in the southern Galactic bulge from 2.3 million red clump stars with Gaia DR3 proper motions
The DECam MAGIC Survey $-$ Mapping the Ancient Galaxy in CaHK: Overview and Summary of Early Science
Kavli Institute for Particle Astrophysics & Cosmology, Stanford University（斯坦福大学卡弗里粒子天体物理与宇宙学研究所）；Fermi National Accelerator Laboratory（费米国家加速器实验室）；Kavli Institute for Cosmological Physics, University of Chicago（芝加哥大学卡弗里宇宙物理学研究所）；Department of Astronomy & Astrophysics, University of Chicago（芝加哥大学天文与天体物理系）；NSF-Simons AI Institute for the Sky (SkAI)（NSF-Simons天空人工智能研究所）；Department of Astronomy, University of Virginia（弗吉尼亚大学天文学系）；Department of Astronomy, Yale University（耶鲁大学天文学系）；Universidade de São Paulo, Instituto de Astronomia, Geofísica e Ciências Atmosféricas（圣保罗大学天文、地球物理与大气科学学院）；Instituto de Alta Investigación, Universidad de Tarapacá（塔拉帕卡大学高级研究所）
Mapping the Interstellar Reddening and Extinction towards Baade's Window Using Minimum Light Colors of ab-type RR Lyrae Stars. Revelations from the De-reddened Color-Magnitude Diagrams
Is the Nuclear Star Cluster a Bulge Fossil Fragment?
University of California, Los Angeles（加州大学洛杉矶分校）；Lund University（隆德大学）；Université Côte d’Azur（蔚蓝海岸大学）；Observatoire de la Côte d’Azur（蔚蓝海岸天文台）；CNRS（法国国家科学研究中心）；Laboratoire Lagrange（拉格朗日实验室）；Space Telescope Science Institute（太空望远镜科学研究所）
