Third data release of the Hyper Suprime-Cam Subaru Strategic Program

Abstract This paper presents the third data release of Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP), a wide-field multi-band imaging survey with 8.2 m telescope. HSC-SSP has three layers (Wide, Deep, and UltraDeep) different area coverages depths, designed to address wide array astrophysical questions. from includes 278 nights observing time covers about 670 deg2 in all five broad-band filters (grizy) at full depth (?26 mag 5? depending on filter) Wide layer. If we include partially observed areas, 1470 deg2. The Deep UltraDeep have $\sim\! 80\%$ originally planned integration times, are considered done, as slightly changed strategy order compensate for various losses. There number updates image processing pipeline. Of particular importance is change sky subtraction algorithm; subtract small scales before detection measurement stages, which significantly reduced false detections. Thanks this other updates, overall quality processed improved since previous release. However, there limitations (for example, pipeline not optimized crowded fields), encourage user check assurance plots well list known issues exploiting data. website ?https://hsc-release.mtk.nao.ac.jp?.