标题： 凯克深场。 I. 观测、归约以及红移z ~ 4、3和2处微弱恒星形成星系的选择 显示英文标题

标题： Keck Deep Fields. I. Observations, Reductions, and the Selection of Faint Star-Forming Galaxies at Redshifts z~4, 3, and 2

摘要： 我们介绍了一个非常深场、R_lim~27的多色图像巡天调查，目标是红移z~4、z~3、z~2.2和z~1.7处非常暗弱的恒星形成星系。 这项在凯克I望远镜上开展的巡天使用了与Steidel团队用于选择这些红移处星系相同的UGRI滤光片系统，从而让我们能够构建出同样选择标准但亮度显著更低的样本。 然而，我们的巡天比Steidel及其团队的工作深入约1.5个星等，使我们能够探测到显著低于特征亮度L*的位置，进而研究高红移星系族群中暗弱成分的性质及红移演化。 该巡天在天空中的三个空间独立区域覆盖了169平方角分的面积，在R<~27的深度范围内包含了427个GRI选样的z~4 LBGs（亮星暴星系）、1481个UGR选样的z~3 LBGs、2417个UGR选样的z~2.2恒星形成星系以及2043个UGR选样的z~1.7恒星形成星系。 在这篇系列论文的第一篇中，我们介绍了该巡天，描述了观测策略和数据处理方法，并概述了z~4、z~3、z~2.2和z~1.7样本的选择过程。 显示英文摘要

摘要： We introduce a very deep, R_lim~27, multicolor imaging survey of very faint star-forming galaxies at z~4, z~3, z~2.2, and z~1.7. This survey, carried out on the Keck I telescope, uses the very same UGRI filter system that is employed by the Steidel team to select galaxies at these redshifts, and thus allows us to construct identically-selected, but much fainter, samples. However, our survey reaches ~1.5 mag deeper than the work of Steidel and his group, letting us probe substantially below the characteristic luminosity L* and thus study the properties and redshift evolution of the faint component of the high-z galaxy population. The survey covers 169 square arcminutes in three spatially independent patches on the sky and -- to R<~27 -- contains 427 GRI-selected z~4 LBGs, 1481 UGR-selected z~3 LBGs, 2417 UGR-selected z~2.2 star-forming galaxies, and 2043 UGR-selected z~1.7 star-forming galaxies. In this paper, the first in a series, we introduce the survey, describe our observing and data reduction strategies, and outline the selection of our z~4, z~3, z~2.2, and z~1.7 samples.