Blanco DECam Bulge Survey (BDBS) II

• Verfasst von: Johnson, Christian I. [VerfasserIn]
• Verfasst von: Rich, Robert Michael [VerfasserIn]
• Verfasst von: Young, Michael D [VerfasserIn]
• Verfasst von: Simion, Iulia T [VerfasserIn]
• Verfasst von: Clarkson, William I [VerfasserIn]
• Verfasst von: Pilachowski, Catherine A [VerfasserIn]
• Verfasst von: Michael, Scott [VerfasserIn]
• Verfasst von: Kunder, Andrea [VerfasserIn]
• Verfasst von: Koch-Hansen, Andreas [VerfasserIn]
• Verfasst von: Vivas, Anna Katherina [VerfasserIn]
• Titel: Blanco DECam Bulge Survey (BDBS) II
• Titelzusatz: project performance, data analysis, and early science results
• Verf.angabe: Christian I. Johnson, Robert Michael Rich, Michael D. Young, Iulia T. Simion, William I. Clarkson, Catherine A. Pilachowski, Scott Michael, Andrea Kunder, Andreas Koch and Anna Katherina Vivas
• E-Jahr: 2020
• Jahr: 03 September 2020
• Umfang: 23 S.
• Fussnoten: Gesehen am 18.01.2021
• Titel Quelle: Enthalten in: Royal Astronomical SocietyMonthly notices of the Royal Astronomical Society
• Ort Quelle: Oxford : Oxford Univ. Press, 1827
• Jahr Quelle: 2020
• Band/Heft Quelle: 499(2020), 2, Seite 2357-2379
• ISSN Quelle: 1365-2966
• DOI: doi:10.1093/mnras/staa2393
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1744906424

Abstract

The Blanco DECam Bulge Survey (BDBS) imaged more than 200 sq deg 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 catalogues, 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 (σ ∼ 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° 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 subgiant branch in M22 as a function of metallicity, the detection of possible extratidal 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.