论文标题
Musubi（Megacam Ultra-Deep调查：$ u^\ ast $ -band Imaging）-Data for Cosmos和SXDS字段
MUSUBI (MegaCam Ultra-deep Survey: $u^\ast$-Band Imaging)-Data for the COSMOS and SXDS Fields
论文作者
论文摘要
Subaru Hyper Suprime-CAM（HSC）战略调查是银河发展和结构形成的最新代代多波段光学成像调查。 HSC调查的“超深”组件提供了$ \ sim3.4 $ deg $^2 $以检测$ \ sim26 $ -28 ab的$ \ sim3.4 $ deg $^2 $，以及cosmos和SXDS字段中的窄带图像。这些图像为深度和区域覆盖范围提供了前所未有的组合，用于研究星系最高$ z \ sim7 $。但是，$ <4000 $ ang的覆盖范围缺乏覆盖范围，这意味着在$ z \ Lessim 3 $上对剩下的紫外线进行了不完整的采样，这是理解后来宇宙时间内恒星质量的迫切需要的。我们在CFHT Megacam的两个HSC Ultra-Deep领域中进行了多年的CFHT $ U^\ AST $ -BAND成像活动。通过包含较浅的档案数据，我们分别在Cosmos和SXDS字段中的中心分别达到$ U^\ ast = 28.1 $和28.4（AB）的5- $σ$深度，以及中央1度$^2 $ fields中的$ u^\ ast = 27.7 $和27.8。图像质量为$ \ gtrsim0.90 $ arcsec，非常适合$ u^\ ast $ band。我们数据的光度和天文质量都非常出色。我们表明，我们的$ u^\ ast $ -band和HSC数据的组合可能导致高质量的光度红移在$ z = 0 $ -3时，以及对星系$ 0.4 <z <z <0.6 $的REST-FRAME UV的强大测量，用于区分绿色valley星系，以区分星星和QuiescentCentencent和QuiescentCentencent。我们公开发布了可容易用于科学研究的$ u^\ ast $ band图像和参考目录。
The Subaru Hyper Suprime-Cam (HSC) Strategic Survey is the latest-generation multi-band optical imaging survey for galaxy evolution and structure formation. The "Ultra-Deep" component of the HSC survey provides $grizy$ broad-band images over $\sim3.4$ deg$^2$ to detection limits of $\sim26$-28 AB, along with narrow-band images, in the COSMOS and the SXDS fields. These images provide an unprecedented combination of depths and area coverage, for the studies galaxies up to $z\sim7$. However, the lack of coverage at $<4000$ Ang implies incomplete sampling of the rest-frame UV at $z\lesssim 3$, which is critically needed for understanding the buildup of stellar mass in the later cosmic time. We conducted a multi-year CFHT $u^\ast$-band imaging campaign in the two HSC Ultra-Deep fields with CFHT MegaCam. By including shallower archival data, we reach 5-$σ$ depths of $u^\ast=28.1$ and 28.4 (AB) at the centers of the COSMOS and SXDS fields, respectively, and $u^\ast=27.7$ and 27.8 in the central 1 deg$^2$ fields. The image quality is $\gtrsim0.90$ arcsec, fairly good for the $u^\ast$ band. Both the photometric and astrometric quality of our data are excellent. We show that the combination of our $u^\ast$-band and HSC data can lead to high-quality photometric redshifts at $z=0$-3, and robust measurements of rest-frame UV on galaxies at $0.4<z<0.6$ for distinguishing green-valley galaxies from star-forming and quiescent galaxies. We publicly release our reduced $u^\ast$-band images and reference catalogs that can be used readily for scientific studies.
