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arXiv · 2501.03513

The S-PLUS Ultra-Short Survey: Photometric Re-calibration with the BEst STar Database

Xiaolu Li·Kai Xiao·Yang Huang·Haibo Yuan·Yanke Tang·Timothy C. Beers·Bowen Huang·Mingyang Ma·Pedro K. Humire·Alvaro Alvarez-Candal·Federico Sestito·Ning Gai·Yongna Mao·Hongrui Gu·Zhenzhao Tao·Lin Yang·Shuai Xu·Rong Hu
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Abstract

We present an independent validation and comprehensive re-calibration of S-PLUS Ultra-Short Survey (USS) DR1 12-band photometry using about 30,000--70,000 standard stars from the BEst STar (BEST) database. We identify spatial variation of zero-point offsets, up to 30--40\,mmag for blue filters ($u$, $J0378$, $J0395$) and 10\,mmag for others, predominantly due to the higher uncertainties of the technique employed in the original USS calibration. Moreover, we detect large- and medium-scale CCD position-dependent systematic errors, up to 50\,mmag, primarily caused by different aperture and flat-field corrections. We then re-calibrate the USS DR1 photometry by correcting the systematic shifts for each tile using second-order two-dimensional polynomial fitting combined with a numerical stellar flat-field correction method. The re-calibrated results from the XPSP and the SCR standards are consistent within 6\,mmag in the USS zero-points, demonstrating both the typical precision of re-calibrated USS photometry and a sixfold improvement in USS zero-point precision. Further validation using SDSS and Pan-STARRS1, as well as LAMOST DR10 and Gaia photometry, also confirms this precision for the re-calibrated USS photometry. Our results clearly demonstrate the capability and the efficiency of the BEST database in improving calibration precision to the milli-magnitude level for wide-field photometric surveys. The re-calibrated USS DR1 photometry is publicly available: doi: 10.12149/101503 (https://nadc.china-vo.org/res/r101504/).

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Xiaolu Li, Kai Xiao, Yang Huang, Haibo Yuan, Yanke Tang, Timothy C. Beers, Bowen Huang, Mingyang Ma, Pedro K. Humire, Alvaro Alvarez-Candal, Federico Sestito, Ning Gai, Yongna Mao, Hongrui Gu, Zhenzhao Tao, Lin Yang, Shuai Xu, Rong Hu. 2025-01-07. The S-PLUS Ultra-Short Survey: Photometric Re-calibration with the BEst STar Database. https://arxiv.org/abs/2501.03513

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