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arXiv · 1812.02745

SDSS-IV MaStar -- A Large and Comprehensive Empirical Stellar Spectral Library: First Release

Renbin Yan·Yanping Chen·Daniel Lazarz·Dmitry Bizyaev·Claudia Maraston·Guy S. Stringfellow·Kyle McCarthy·Sofia Meneses-Goytia·David R. Law·Daniel Thomas·Jesus Falcon Barroso·José R. Sánchez-Gallego·Edward Schlafly·Zheng Zheng·Maria Argudo-Fernández·Rachael L. Beaton·Timothy C. Beers·Matthew Bershady·Michael R. Blanton·Joel Brownstein·Kevin Bundy·Kenneth C. Chambers·Brian Cherinka·Nathan De Lee·Niv Drory·Lluís Galbany·Jon Holtzman·Julie Imig·Nick Kaiser·Karen Kinemuchi·Chao Liu·A-Li Luo·Eugene Magnier·Steven Majewski·Preethi Nair·Audrey Oravetz·Daniel Oravetz·Kaike Pan·Jennifer Sobeck·Keivan Stassun·Michael Talbot·Christy Tremonti·Christopher Waters·Anne-Marie Weijmans·Ronald Wilhelm·Gail Zasowski·Gang Zhao·Yong-Heng Zhao
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Abstract

We present the first release of the MaNGA Stellar Library (MaStar), which is a large, well-calibrated, high-quality empirical library covering the wavelength range of 3,622-10,354A at a resolving power of R~1800. The spectra were obtained using the same instrument as used by the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) project, by piggybacking on the SDSS-IV/APOGEE-2N observations. Compared to previous empirical libraries, the MaStar library will have a higher number of stars and a more comprehensive stellar-parameter coverage, especially of cool dwarfs, low-metallicity stars, and stars with different [alpha/Fe], achieved by a sophisticated target selection strategy that takes advantage of stellar-parameter catalogs from the literature. This empirical library will provide a new basis for stellar population synthesis, and is particularly well-suited for stellar-population analysis of MaNGA galaxies. The first version of the library contains 8646 high-quality per-visit spectra for 3321 unique stars. Compared to photometry, the relative flux calibration of the library is accurate to 3.9% in g-r, 2.7% in r-i, and 2.2% in i-z. The data are released as part of Sloan Digital Sky Survey Data Release 15. We expect the final release of the library to contain more than 10,000 stars.

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Renbin Yan, Yanping Chen, Daniel Lazarz, Dmitry Bizyaev, Claudia Maraston, Guy S. Stringfellow, Kyle McCarthy, Sofia Meneses-Goytia, David R. Law, Daniel Thomas, Jesus Falcon Barroso, José R. Sánchez-Gallego, Edward Schlafly, Zheng Zheng, Maria Argudo-Fernández, Rachael L. Beaton, Timothy C. Beers, Matthew Bershady, Michael R. Blanton, Joel Brownstein, Kevin Bundy, Kenneth C. Chambers, Brian Cherinka, Nathan De Lee, Niv Drory, Lluís Galbany, Jon Holtzman, Julie Imig, Nick Kaiser, Karen Kinemuchi, Chao Liu, A-Li Luo, Eugene Magnier, Steven Majewski, Preethi Nair, Audrey Oravetz, Daniel Oravetz, Kaike Pan, Jennifer Sobeck, Keivan Stassun, Michael Talbot, Christy Tremonti, Christopher Waters, Anne-Marie Weijmans, Ronald Wilhelm, Gail Zasowski, Gang Zhao, Yong-Heng Zhao. 2019-11-18. SDSS-IV MaStar -- A Large and Comprehensive Empirical Stellar Spectral Library: First Release. https://doi.org/10.3847/1538-4357%2Fab3ebc

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